Thursday, October 31, 2019

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3143

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3143

3900 kg (8600 lb) GVW

* Control Module References (See: Testing and Inspection/Programming and Relearning) for module replacement, setup, and programming

U2174

DTC U2105-U2199

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System

Check - Vehicle) prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an

overview of the diagnostic approach.

* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure

Instructions) provides an overview of each diagnostic category.

DTC Descriptor

DTC U2142 00

- Lost Communication With Yaw Rate Sensor (YRS)

Circuit/System Description

Modules connected to the CAN bus serial data circuits monitor for serial data communications during normal vehicle operation. Operating

information and commands are exchanged among the modules. The modules have prerecorded information about what messages are needed to be

exchanged on the serial data circuits. The messages are supervised and also, some periodic messages are used by the receiver module as an

availability indication of the transmitter module. Each message contains the identification number of the transmitter module.

The electronic brake control module (EBCM) activates the other modules connected to the CAN serial data circuits by applying voltage when the

ignition key is in ACC, ON or START. The EBCM, Yaw Rate and Lateral Acceleration Sensor are the only modules connected to the CAN bus

serial data circuits. For more information on CAN bus serial data refer to Data Link Communications Description and Operation (See: Powertrain

Management/Computers and Control Systems/Information Bus/Description and Operation).

Conditions for Running the DTC

* The system voltage is between 9-16 volts.

* The vehicle power mode master requires serial data communication to occur.

Conditions for Setting the DTC

A supervised periodic message that includes the transmitter module availability has not been received.

Action Taken When the DTC Sets

* The vehicle stability enhancement system (VSES), if equipped, and traction control system (TCS) will not function.

* System OFF lamps will illuminate for these systems.

Conditions for Clearing the DTC

* A current DTC clears when the malfunction is no longer present.

* A history DTC clears when the module ignition cycle counter reaches the reset threshold of 50, without a repeat of the malfunction.

Diagnostic Aids

* Sometimes, while diagnosing a specific customer concern or after a repair, you may notice a history U-code present. However, there is no

associated "current" or "active" status. Loss-of- communication U-codes such as these can set for a variety of reasons. Many times, they are

transparent to the vehicle operator and technician, and/or have no associated symptoms. Eventually, they will erase themselves automatically

after a number of fault-free ignition cycles. This condition would most likely be attributed to one of these scenarios:

- A control module on the data communication circuit was disconnected while the communication circuit is awake.

- Power to one or more modules was interrupted during diagnosis.

- A low battery condition was present, so some control modules stop communicating when battery voltage drops below a certain threshold.

- Battery power was restored to the vehicle and control modules on the communication circuit did not all re-initialize at the same time.

- If a loss-of-communication U-code appears in history for no apparent reason, it is most likely associated with one of the scenarios above.

These are all temporary conditions and should never be interpreted as an intermittent fault, causing you to replace a part.

* A control module may have a U-code stored in history that does not require any repairs. Issues with late or corrupted messages between

control modules can be temporary with no apparent symptom or complaint; this does not mean the control module is faulty. Do not replace a

control module based only on a history U-code.

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3142

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3142

* Communication may be available between the BCM and the scan tool with either the low or high speed GMLAN serial data system

inoperative. This condition is due to the BCM using both the low and high speed GMLAN systems.

* Use to determine if the module uses high or low speed GMLAN serial data communications.

* Some control modules may not have internal protection for specific control circuits and may open a B+ or ignition fuse. If a fuse is open and

the B+ or ignition circuit is not shorted to ground, ensure none of the control circuits are shorted to ground before replacing the control

module.

* This diagnostic can be used for any control module that is not communicating, regardless of the type of serial data circuit it is connected to,

providing the vehicle is equipped with the control module.

Reference Information

Schematic Reference

* Data Communication Schematics (See: Powertrain Management/Computers and Control Systems/Information Bus/Diagrams/Electrical

Diagrams)

* Antilock Brake System Schematics (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Diagrams/Electrical

Diagrams) for the ABS - Hybrid

* Antilock Brake System Schematics (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Diagrams/Electrical

Diagrams) for the ABS - Non-Hybrid Less than 3900 kg (8600 lb) GVW

* Antilock Brake System Schematics (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Diagrams/Electrical

Diagrams) for the ABS - Non-Hybrid Greater than/Equal to 3900 kg (8600 lb) GVW

Connector End View Reference

Component Connector End Views (See: Diagrams/Connector Views)

Description and Operation

Data Link Communications Description and Operation (See: Powertrain Management/Computers and Control Systems/Information

Bus/Description and Operation)

Electrical Information Reference

* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit

Testing/Circuit Testing)

* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Connector Repairs/Connector Repairs)

* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General

Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)

* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring

Repairs/Wiring Repairs)

Scan Tool Reference

Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector of the yaw rate sensor.

2. Ignition ON, verify that a test lamp illuminates between the module voltage circuit and ground.

瀚慖f the test lamp does not illuminate, test the circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the

EBCM.

3. Ignition OFF, test for less than 5 ohms between the module ground circuits and ground.

瀚慖f greater than the specified value, test the ground circuit for an open/high resistance. If the circuit tests normal, replace the EBCM.

4. If all circuits test normal, replace the yaw rate sensor.

Repair Instructions

Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.

* GMLAN Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Wiring Repairs/GMLAN Wiring Repairs)

* ABS Description and Operation (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Description and

Operation/ABS Description and Operation) for the ABS - Hybrid

* Vehicle Yaw Sensor with Vehicle Lateral Accelerometer Replacement (See: Brakes and Traction Control/Antilock Brakes / Traction

Control Systems/Yaw Rate Sensor/Service and Repair/Less than 3900 kg (8600 lb) GVW) for the ABS - Non-Hybrid Less than 3900 kg

(8600 lb) GVW

* Vehicle Yaw Sensor with Vehicle Lateral Accelerometer Replacement (See: Brakes and Traction Control/Antilock Brakes / Traction

Control Systems/Yaw Rate Sensor/Service and Repair/Less than 3900 kg (8600 lb) GVW) for the ABS - Non-Hybrid Greater than/Equal to

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3141

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3141

U2173

DTC U2105-U2199

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System

Check - Vehicle) prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an

overview of the diagnostic approach.

* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure

Instructions) provides an overview of each diagnostic category.

DTC Descriptor

DTC U2142 00

- Lost Communication With Yaw Rate Sensor (YRS)

Circuit/System Description

Modules connected to the CAN bus serial data circuits monitor for serial data communications during normal vehicle operation. Operating

information and commands are exchanged among the modules. The modules have prerecorded information about what messages are needed to be

exchanged on the serial data circuits. The messages are supervised and also, some periodic messages are used by the receiver module as an

availability indication of the transmitter module. Each message contains the identification number of the transmitter module.

The electronic brake control module (EBCM) activates the other modules connected to the CAN serial data circuits by applying voltage when the

ignition key is in ACC, ON or START. The EBCM, Yaw Rate and Lateral Acceleration Sensor are the only modules connected to the CAN bus

serial data circuits. For more information on CAN bus serial data refer to Data Link Communications Description and Operation (See: Powertrain

Management/Computers and Control Systems/Information Bus/Description and Operation).

Conditions for Running the DTC

* The system voltage is between 9-16 volts.

* The vehicle power mode master requires serial data communication to occur.

Conditions for Setting the DTC

A supervised periodic message that includes the transmitter module availability has not been received.

Action Taken When the DTC Sets

* The vehicle stability enhancement system (VSES), if equipped, and traction control system (TCS) will not function.

* System OFF lamps will illuminate for these systems.

Conditions for Clearing the DTC

* A current DTC clears when the malfunction is no longer present.

* A history DTC clears when the module ignition cycle counter reaches the reset threshold of 50, without a repeat of the malfunction.

Diagnostic Aids

* Sometimes, while diagnosing a specific customer concern or after a repair, you may notice a history U-code present. However, there is no

associated "current" or "active" status. Loss-of- communication U-codes such as these can set for a variety of reasons. Many times, they are

transparent to the vehicle operator and technician, and/or have no associated symptoms. Eventually, they will erase themselves automatically

after a number of fault-free ignition cycles. This condition would most likely be attributed to one of these scenarios:

- A control module on the data communication circuit was disconnected while the communication circuit is awake.

- Power to one or more modules was interrupted during diagnosis.

- A low battery condition was present, so some control modules stop communicating when battery voltage drops below a certain threshold.

- Battery power was restored to the vehicle and control modules on the communication circuit did not all re-initialize at the same time.

- If a loss-of-communication U-code appears in history for no apparent reason, it is most likely associated with one of the scenarios above.

These are all temporary conditions and should never be interpreted as an intermittent fault, causing you to replace a part.

* A control module may have a U-code stored in history that does not require any repairs. Issues with late or corrupted messages between

control modules can be temporary with no apparent symptom or complaint; this does not mean the control module is faulty. Do not replace a

control module based only on a history U-code.

* Do not replace a control module reporting a U-code. The U-code identifies which control module needs to be diagnosed for a communication

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3140

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3140

* Some control modules may not have internal protection for specific control circuits and may open a B+ or ignition fuse. If a fuse is open and

the B+ or ignition circuit is not shorted to ground, ensure none of the control circuits are shorted to ground before replacing the control

module.

* This diagnostic can be used for any control module that is not communicating, regardless of the type of serial data circuit it is connected to,

providing the vehicle is equipped with the control module.

Reference Information

Schematic Reference

* Data Communication Schematics (See: Powertrain Management/Computers and Control Systems/Information Bus/Diagrams/Electrical

Diagrams)

* Antilock Brake System Schematics (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Diagrams/Electrical

Diagrams) for the ABS - Hybrid

* Antilock Brake System Schematics (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Diagrams/Electrical

Diagrams) for the ABS - Non-Hybrid Less than 3900 kg (8600 lb) GVW

* Antilock Brake System Schematics (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Diagrams/Electrical

Diagrams) for the ABS - Non-Hybrid Greater than/Equal to 3900 kg (8600 lb) GVW

Connector End View Reference

Component Connector End Views (See: Diagrams/Connector Views)

Description and Operation

Data Link Communications Description and Operation (See: Powertrain Management/Computers and Control Systems/Information

Bus/Description and Operation)

Electrical Information Reference

* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit

Testing/Circuit Testing)

* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Connector Repairs/Connector Repairs)

* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General

Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)

* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring

Repairs/Wiring Repairs)

Scan Tool Reference

Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector of the yaw rate sensor.

2. Ignition ON, verify that a test lamp illuminates between the module voltage circuit and ground.

瀚慖f the test lamp does not illuminate, test the circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the

EBCM.

3. Ignition OFF, test for less than 5 ohms between the module ground circuits and ground.

瀚慖f greater than the specified value, test the ground circuit for an open/high resistance. If the circuit tests normal, replace the EBCM.

4. If all circuits test normal, replace the yaw rate sensor.

Repair Instructions

Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.

* GMLAN Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Wiring Repairs/GMLAN Wiring Repairs)

* ABS Description and Operation (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Description and

Operation/ABS Description and Operation) for the ABS - Hybrid

* Vehicle Yaw Sensor with Vehicle Lateral Accelerometer Replacement (See: Brakes and Traction Control/Antilock Brakes / Traction

Control Systems/Yaw Rate Sensor/Service and Repair/Less than 3900 kg (8600 lb) GVW) for the ABS - Non-Hybrid Less than 3900 kg

(8600 lb) GVW

* Vehicle Yaw Sensor with Vehicle Lateral Accelerometer Replacement (See: Brakes and Traction Control/Antilock Brakes / Traction

Control Systems/Yaw Rate Sensor/Service and Repair/Less than 3900 kg (8600 lb) GVW) for the ABS - Non-Hybrid Greater than/Equal to

3900 kg (8600 lb) GVW

* Control Module References (See: Testing and Inspection/Programming and Relearning) for module replacement, setup, and programming

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3139

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3139

DTC U2105-U2199

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System

Check - Vehicle) prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an

overview of the diagnostic approach.

* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure

Instructions) provides an overview of each diagnostic category.

DTC Descriptor

DTC U2142 00

- Lost Communication With Yaw Rate Sensor (YRS)

Circuit/System Description

Modules connected to the CAN bus serial data circuits monitor for serial data communications during normal vehicle operation. Operating

information and commands are exchanged among the modules. The modules have prerecorded information about what messages are needed to be

exchanged on the serial data circuits. The messages are supervised and also, some periodic messages are used by the receiver module as an

availability indication of the transmitter module. Each message contains the identification number of the transmitter module.

The electronic brake control module (EBCM) activates the other modules connected to the CAN serial data circuits by applying voltage when the

ignition key is in ACC, ON or START. The EBCM, Yaw Rate and Lateral Acceleration Sensor are the only modules connected to the CAN bus

serial data circuits. For more information on CAN bus serial data refer to Data Link Communications Description and Operation (See: Powertrain

Management/Computers and Control Systems/Information Bus/Description and Operation).

Conditions for Running the DTC

* The system voltage is between 9-16 volts.

* The vehicle power mode master requires serial data communication to occur.

Conditions for Setting the DTC

A supervised periodic message that includes the transmitter module availability has not been received.

Action Taken When the DTC Sets

* The vehicle stability enhancement system (VSES), if equipped, and traction control system (TCS) will not function.

* System OFF lamps will illuminate for these systems.

Conditions for Clearing the DTC

* A current DTC clears when the malfunction is no longer present.

* A history DTC clears when the module ignition cycle counter reaches the reset threshold of 50, without a repeat of the malfunction.

Diagnostic Aids

* Sometimes, while diagnosing a specific customer concern or after a repair, you may notice a history U-code present. However, there is no

associated "current" or "active" status. Loss-of- communication U-codes such as these can set for a variety of reasons. Many times, they are

transparent to the vehicle operator and technician, and/or have no associated symptoms. Eventually, they will erase themselves automatically

after a number of fault-free ignition cycles. This condition would most likely be attributed to one of these scenarios:

- A control module on the data communication circuit was disconnected while the communication circuit is awake.

- Power to one or more modules was interrupted during diagnosis.

- A low battery condition was present, so some control modules stop communicating when battery voltage drops below a certain threshold.

- Battery power was restored to the vehicle and control modules on the communication circuit did not all re-initialize at the same time.

- If a loss-of-communication U-code appears in history for no apparent reason, it is most likely associated with one of the scenarios above.

These are all temporary conditions and should never be interpreted as an intermittent fault, causing you to replace a part.

* A control module may have a U-code stored in history that does not require any repairs. Issues with late or corrupted messages between

control modules can be temporary with no apparent symptom or complaint; this does not mean the control module is faulty. Do not replace a

control module based only on a history U-code.

* Do not replace a control module reporting a U-code. The U-code identifies which control module needs to be diagnosed for a communication

issue.

* Communication may be available between the BCM and the scan tool with either the low or high speed GMLAN serial data system

inoperative. This condition is due to the BCM using both the low and high speed GMLAN systems.

* Use to determine if the module uses high or low speed GMLAN serial data communications.

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3138

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3138

module.

* This diagnostic can be used for any control module that is not communicating, regardless of the type of serial data circuit it is connected to,

providing the vehicle is equipped with the control module.

Reference Information

Schematic Reference

* Data Communication Schematics (See: Powertrain Management/Computers and Control Systems/Information Bus/Diagrams/Electrical

Diagrams)

* Antilock Brake System Schematics (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Diagrams/Electrical

Diagrams) for the ABS - Hybrid

* Antilock Brake System Schematics (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Diagrams/Electrical

Diagrams) for the ABS - Non-Hybrid Less than 3900 kg (8600 lb) GVW

* Antilock Brake System Schematics (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Diagrams/Electrical

Diagrams) for the ABS - Non-Hybrid Greater than/Equal to 3900 kg (8600 lb) GVW

Connector End View Reference

Component Connector End Views (See: Diagrams/Connector Views)

Description and Operation

Data Link Communications Description and Operation (See: Powertrain Management/Computers and Control Systems/Information

Bus/Description and Operation)

Electrical Information Reference

* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit

Testing/Circuit Testing)

* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Connector Repairs/Connector Repairs)

* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General

Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)

* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring

Repairs/Wiring Repairs)

Scan Tool Reference

Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector of the yaw rate sensor.

2. Ignition ON, verify that a test lamp illuminates between the module voltage circuit and ground.

瀚慖f the test lamp does not illuminate, test the circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the

EBCM.

3. Ignition OFF, test for less than 5 ohms between the module ground circuits and ground.

瀚慖f greater than the specified value, test the ground circuit for an open/high resistance. If the circuit tests normal, replace the EBCM.

4. If all circuits test normal, replace the yaw rate sensor.

Repair Instructions

Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.

* GMLAN Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Wiring Repairs/GMLAN Wiring Repairs)

* ABS Description and Operation (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Description and

Operation/ABS Description and Operation) for the ABS - Hybrid

* Vehicle Yaw Sensor with Vehicle Lateral Accelerometer Replacement (See: Brakes and Traction Control/Antilock Brakes / Traction

Control Systems/Yaw Rate Sensor/Service and Repair/Less than 3900 kg (8600 lb) GVW) for the ABS - Non-Hybrid Less than 3900 kg

(8600 lb) GVW

* Vehicle Yaw Sensor with Vehicle Lateral Accelerometer Replacement (See: Brakes and Traction Control/Antilock Brakes / Traction

Control Systems/Yaw Rate Sensor/Service and Repair/Less than 3900 kg (8600 lb) GVW) for the ABS - Non-Hybrid Greater than/Equal to

3900 kg (8600 lb) GVW

* Control Module References (See: Testing and Inspection/Programming and Relearning) for module replacement, setup, and programming

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3137

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3137

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System

Check - Vehicle) prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an

overview of the diagnostic approach.

* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure

Instructions) provides an overview of each diagnostic category.

DTC Descriptor

DTC U2142 00

- Lost Communication With Yaw Rate Sensor (YRS)

Circuit/System Description

Modules connected to the CAN bus serial data circuits monitor for serial data communications during normal vehicle operation. Operating

information and commands are exchanged among the modules. The modules have prerecorded information about what messages are needed to be

exchanged on the serial data circuits. The messages are supervised and also, some periodic messages are used by the receiver module as an

availability indication of the transmitter module. Each message contains the identification number of the transmitter module.

The electronic brake control module (EBCM) activates the other modules connected to the CAN serial data circuits by applying voltage when the

ignition key is in ACC, ON or START. The EBCM, Yaw Rate and Lateral Acceleration Sensor are the only modules connected to the CAN bus

serial data circuits. For more information on CAN bus serial data refer to Data Link Communications Description and Operation (See: Powertrain

Management/Computers and Control Systems/Information Bus/Description and Operation).

Conditions for Running the DTC

* The system voltage is between 9-16 volts.

* The vehicle power mode master requires serial data communication to occur.

Conditions for Setting the DTC

A supervised periodic message that includes the transmitter module availability has not been received.

Action Taken When the DTC Sets

* The vehicle stability enhancement system (VSES), if equipped, and traction control system (TCS) will not function.

* System OFF lamps will illuminate for these systems.

Conditions for Clearing the DTC

* A current DTC clears when the malfunction is no longer present.

* A history DTC clears when the module ignition cycle counter reaches the reset threshold of 50, without a repeat of the malfunction.

Diagnostic Aids

* Sometimes, while diagnosing a specific customer concern or after a repair, you may notice a history U-code present. However, there is no

associated "current" or "active" status. Loss-of- communication U-codes such as these can set for a variety of reasons. Many times, they are

transparent to the vehicle operator and technician, and/or have no associated symptoms. Eventually, they will erase themselves automatically

after a number of fault-free ignition cycles. This condition would most likely be attributed to one of these scenarios:

- A control module on the data communication circuit was disconnected while the communication circuit is awake.

- Power to one or more modules was interrupted during diagnosis.

- A low battery condition was present, so some control modules stop communicating when battery voltage drops below a certain threshold.

- Battery power was restored to the vehicle and control modules on the communication circuit did not all re-initialize at the same time.

- If a loss-of-communication U-code appears in history for no apparent reason, it is most likely associated with one of the scenarios above.

These are all temporary conditions and should never be interpreted as an intermittent fault, causing you to replace a part.

* A control module may have a U-code stored in history that does not require any repairs. Issues with late or corrupted messages between

control modules can be temporary with no apparent symptom or complaint; this does not mean the control module is faulty. Do not replace a

control module based only on a history U-code.

* Do not replace a control module reporting a U-code. The U-code identifies which control module needs to be diagnosed for a communication

issue.

* Communication may be available between the BCM and the scan tool with either the low or high speed GMLAN serial data system

inoperative. This condition is due to the BCM using both the low and high speed GMLAN systems.

* Use to determine if the module uses high or low speed GMLAN serial data communications.

* Some control modules may not have internal protection for specific control circuits and may open a B+ or ignition fuse. If a fuse is open and

the B+ or ignition circuit is not shorted to ground, ensure none of the control circuits are shorted to ground before replacing the control

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3136

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3136

Reference Information

Schematic Reference

* Data Communication Schematics (See: Powertrain Management/Computers and Control Systems/Information Bus/Diagrams/Electrical

Diagrams)

* Antilock Brake System Schematics (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Diagrams/Electrical

Diagrams) for the ABS - Hybrid

* Antilock Brake System Schematics (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Diagrams/Electrical

Diagrams) for the ABS - Non-Hybrid Less than 3900 kg (8600 lb) GVW

* Antilock Brake System Schematics (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Diagrams/Electrical

Diagrams) for the ABS - Non-Hybrid Greater than/Equal to 3900 kg (8600 lb) GVW

Connector End View Reference

Component Connector End Views (See: Diagrams/Connector Views)

Description and Operation

Data Link Communications Description and Operation (See: Powertrain Management/Computers and Control Systems/Information

Bus/Description and Operation)

Electrical Information Reference

* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit

Testing/Circuit Testing)

* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Connector Repairs/Connector Repairs)

* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General

Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)

* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring

Repairs/Wiring Repairs)

Scan Tool Reference

Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector of the yaw rate sensor.

2. Ignition ON, verify that a test lamp illuminates between the module voltage circuit and ground.

瀚慖f the test lamp does not illuminate, test the circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the

EBCM.

3. Ignition OFF, test for less than 5 ohms between the module ground circuits and ground.

瀚慖f greater than the specified value, test the ground circuit for an open/high resistance. If the circuit tests normal, replace the EBCM.

4. If all circuits test normal, replace the yaw rate sensor.

Repair Instructions

Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.

* GMLAN Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Wiring Repairs/GMLAN Wiring Repairs)

* ABS Description and Operation (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Description and

Operation/ABS Description and Operation) for the ABS - Hybrid

* Vehicle Yaw Sensor with Vehicle Lateral Accelerometer Replacement (See: Brakes and Traction Control/Antilock Brakes / Traction

Control Systems/Yaw Rate Sensor/Service and Repair/Less than 3900 kg (8600 lb) GVW) for the ABS - Non-Hybrid Less than 3900 kg

(8600 lb) GVW

* Vehicle Yaw Sensor with Vehicle Lateral Accelerometer Replacement (See: Brakes and Traction Control/Antilock Brakes / Traction

Control Systems/Yaw Rate Sensor/Service and Repair/Less than 3900 kg (8600 lb) GVW) for the ABS - Non-Hybrid Greater than/Equal to

3900 kg (8600 lb) GVW

* Control Module References (See: Testing and Inspection/Programming and Relearning) for module replacement, setup, and programming

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3135

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3135

Check - Vehicle) prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an

overview of the diagnostic approach.

* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure

Instructions) provides an overview of each diagnostic category.

DTC Descriptor

DTC U2142 00

- Lost Communication With Yaw Rate Sensor (YRS)

Circuit/System Description

Modules connected to the CAN bus serial data circuits monitor for serial data communications during normal vehicle operation. Operating

information and commands are exchanged among the modules. The modules have prerecorded information about what messages are needed to be

exchanged on the serial data circuits. The messages are supervised and also, some periodic messages are used by the receiver module as an

availability indication of the transmitter module. Each message contains the identification number of the transmitter module.

The electronic brake control module (EBCM) activates the other modules connected to the CAN serial data circuits by applying voltage when the

ignition key is in ACC, ON or START. The EBCM, Yaw Rate and Lateral Acceleration Sensor are the only modules connected to the CAN bus

serial data circuits. For more information on CAN bus serial data refer to Data Link Communications Description and Operation (See: Powertrain

Management/Computers and Control Systems/Information Bus/Description and Operation).

Conditions for Running the DTC

* The system voltage is between 9-16 volts.

* The vehicle power mode master requires serial data communication to occur.

Conditions for Setting the DTC

A supervised periodic message that includes the transmitter module availability has not been received.

Action Taken When the DTC Sets

* The vehicle stability enhancement system (VSES), if equipped, and traction control system (TCS) will not function.

* System OFF lamps will illuminate for these systems.

Conditions for Clearing the DTC

* A current DTC clears when the malfunction is no longer present.

* A history DTC clears when the module ignition cycle counter reaches the reset threshold of 50, without a repeat of the malfunction.

Diagnostic Aids

* Sometimes, while diagnosing a specific customer concern or after a repair, you may notice a history U-code present. However, there is no

associated "current" or "active" status. Loss-of- communication U-codes such as these can set for a variety of reasons. Many times, they are

transparent to the vehicle operator and technician, and/or have no associated symptoms. Eventually, they will erase themselves automatically

after a number of fault-free ignition cycles. This condition would most likely be attributed to one of these scenarios:

- A control module on the data communication circuit was disconnected while the communication circuit is awake.

- Power to one or more modules was interrupted during diagnosis.

- A low battery condition was present, so some control modules stop communicating when battery voltage drops below a certain threshold.

- Battery power was restored to the vehicle and control modules on the communication circuit did not all re-initialize at the same time.

- If a loss-of-communication U-code appears in history for no apparent reason, it is most likely associated with one of the scenarios above.

These are all temporary conditions and should never be interpreted as an intermittent fault, causing you to replace a part.

* A control module may have a U-code stored in history that does not require any repairs. Issues with late or corrupted messages between

control modules can be temporary with no apparent symptom or complaint; this does not mean the control module is faulty. Do not replace a

control module based only on a history U-code.

* Do not replace a control module reporting a U-code. The U-code identifies which control module needs to be diagnosed for a communication

issue.

* Communication may be available between the BCM and the scan tool with either the low or high speed GMLAN serial data system

inoperative. This condition is due to the BCM using both the low and high speed GMLAN systems.

* Use to determine if the module uses high or low speed GMLAN serial data communications.

* Some control modules may not have internal protection for specific control circuits and may open a B+ or ignition fuse. If a fuse is open and

the B+ or ignition circuit is not shorted to ground, ensure none of the control circuits are shorted to ground before replacing the control

module.

* This diagnostic can be used for any control module that is not communicating, regardless of the type of serial data circuit it is connected to,

providing the vehicle is equipped with the control module.

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3134

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3134

* Data Communication Schematics (See: Powertrain Management/Computers and Control Systems/Information Bus/Diagrams/Electrical

Diagrams)

* Antilock Brake System Schematics (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Diagrams/Electrical

Diagrams) for the ABS - Hybrid

* Antilock Brake System Schematics (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Diagrams/Electrical

Diagrams) for the ABS - Non-Hybrid Less than 3900 kg (8600 lb) GVW

* Antilock Brake System Schematics (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Diagrams/Electrical

Diagrams) for the ABS - Non-Hybrid Greater than/Equal to 3900 kg (8600 lb) GVW

Connector End View Reference

Component Connector End Views (See: Diagrams/Connector Views)

Description and Operation

Data Link Communications Description and Operation (See: Powertrain Management/Computers and Control Systems/Information

Bus/Description and Operation)

Electrical Information Reference

* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit

Testing/Circuit Testing)

* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Connector Repairs/Connector Repairs)

* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General

Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)

* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring

Repairs/Wiring Repairs)

Scan Tool Reference

Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector of the yaw rate sensor.

2. Ignition ON, verify that a test lamp illuminates between the module voltage circuit and ground.

瀚慖f the test lamp does not illuminate, test the circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the

EBCM.

3. Ignition OFF, test for less than 5 ohms between the module ground circuits and ground.

瀚慖f greater than the specified value, test the ground circuit for an open/high resistance. If the circuit tests normal, replace the EBCM.

4. If all circuits test normal, replace the yaw rate sensor.

Repair Instructions

Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.

* GMLAN Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Wiring Repairs/GMLAN Wiring Repairs)

* ABS Description and Operation (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Description and

Operation/ABS Description and Operation) for the ABS - Hybrid

* Vehicle Yaw Sensor with Vehicle Lateral Accelerometer Replacement (See: Brakes and Traction Control/Antilock Brakes / Traction

Control Systems/Yaw Rate Sensor/Service and Repair/Less than 3900 kg (8600 lb) GVW) for the ABS - Non-Hybrid Less than 3900 kg

(8600 lb) GVW

* Vehicle Yaw Sensor with Vehicle Lateral Accelerometer Replacement (See: Brakes and Traction Control/Antilock Brakes / Traction

Control Systems/Yaw Rate Sensor/Service and Repair/Less than 3900 kg (8600 lb) GVW) for the ABS - Non-Hybrid Greater than/Equal to

3900 kg (8600 lb) GVW

* Control Module References (See: Testing and Inspection/Programming and Relearning) for module replacement, setup, and programming

U2170

DTC U2105-U2199

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3133

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3133

* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure

Instructions) provides an overview of each diagnostic category.

DTC Descriptor

DTC U2142 00

- Lost Communication With Yaw Rate Sensor (YRS)

Circuit/System Description

Modules connected to the CAN bus serial data circuits monitor for serial data communications during normal vehicle operation. Operating

information and commands are exchanged among the modules. The modules have prerecorded information about what messages are needed to be

exchanged on the serial data circuits. The messages are supervised and also, some periodic messages are used by the receiver module as an

availability indication of the transmitter module. Each message contains the identification number of the transmitter module.

The electronic brake control module (EBCM) activates the other modules connected to the CAN serial data circuits by applying voltage when the

ignition key is in ACC, ON or START. The EBCM, Yaw Rate and Lateral Acceleration Sensor are the only modules connected to the CAN bus

serial data circuits. For more information on CAN bus serial data refer to Data Link Communications Description and Operation (See: Powertrain

Management/Computers and Control Systems/Information Bus/Description and Operation).

Conditions for Running the DTC

* The system voltage is between 9-16 volts.

* The vehicle power mode master requires serial data communication to occur.

Conditions for Setting the DTC

A supervised periodic message that includes the transmitter module availability has not been received.

Action Taken When the DTC Sets

* The vehicle stability enhancement system (VSES), if equipped, and traction control system (TCS) will not function.

* System OFF lamps will illuminate for these systems.

Conditions for Clearing the DTC

* A current DTC clears when the malfunction is no longer present.

* A history DTC clears when the module ignition cycle counter reaches the reset threshold of 50, without a repeat of the malfunction.

Diagnostic Aids

* Sometimes, while diagnosing a specific customer concern or after a repair, you may notice a history U-code present. However, there is no

associated "current" or "active" status. Loss-of- communication U-codes such as these can set for a variety of reasons. Many times, they are

transparent to the vehicle operator and technician, and/or have no associated symptoms. Eventually, they will erase themselves automatically

after a number of fault-free ignition cycles. This condition would most likely be attributed to one of these scenarios:

- A control module on the data communication circuit was disconnected while the communication circuit is awake.

- Power to one or more modules was interrupted during diagnosis.

- A low battery condition was present, so some control modules stop communicating when battery voltage drops below a certain threshold.

- Battery power was restored to the vehicle and control modules on the communication circuit did not all re-initialize at the same time.

- If a loss-of-communication U-code appears in history for no apparent reason, it is most likely associated with one of the scenarios above.

These are all temporary conditions and should never be interpreted as an intermittent fault, causing you to replace a part.

* A control module may have a U-code stored in history that does not require any repairs. Issues with late or corrupted messages between

control modules can be temporary with no apparent symptom or complaint; this does not mean the control module is faulty. Do not replace a

control module based only on a history U-code.

* Do not replace a control module reporting a U-code. The U-code identifies which control module needs to be diagnosed for a communication

issue.

* Communication may be available between the BCM and the scan tool with either the low or high speed GMLAN serial data system

inoperative. This condition is due to the BCM using both the low and high speed GMLAN systems.

* Use to determine if the module uses high or low speed GMLAN serial data communications.

* Some control modules may not have internal protection for specific control circuits and may open a B+ or ignition fuse. If a fuse is open and

the B+ or ignition circuit is not shorted to ground, ensure none of the control circuits are shorted to ground before replacing the control

module.

* This diagnostic can be used for any control module that is not communicating, regardless of the type of serial data circuit it is connected to,

providing the vehicle is equipped with the control module.

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3132

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3132

* Antilock Brake System Schematics (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Diagrams/Electrical

Diagrams) for the ABS - Hybrid

* Antilock Brake System Schematics (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Diagrams/Electrical

Diagrams) for the ABS - Non-Hybrid Less than 3900 kg (8600 lb) GVW

* Antilock Brake System Schematics (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Diagrams/Electrical

Diagrams) for the ABS - Non-Hybrid Greater than/Equal to 3900 kg (8600 lb) GVW

Connector End View Reference

Component Connector End Views (See: Diagrams/Connector Views)

Description and Operation

Data Link Communications Description and Operation (See: Powertrain Management/Computers and Control Systems/Information

Bus/Description and Operation)

Electrical Information Reference

* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit

Testing/Circuit Testing)

* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Connector Repairs/Connector Repairs)

* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General

Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)

* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring

Repairs/Wiring Repairs)

Scan Tool Reference

Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector of the yaw rate sensor.

2. Ignition ON, verify that a test lamp illuminates between the module voltage circuit and ground.

瀚慖f the test lamp does not illuminate, test the circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the

EBCM.

3. Ignition OFF, test for less than 5 ohms between the module ground circuits and ground.

瀚慖f greater than the specified value, test the ground circuit for an open/high resistance. If the circuit tests normal, replace the EBCM.

4. If all circuits test normal, replace the yaw rate sensor.

Repair Instructions

Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.

* GMLAN Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Wiring Repairs/GMLAN Wiring Repairs)

* ABS Description and Operation (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Description and

Operation/ABS Description and Operation) for the ABS - Hybrid

* Vehicle Yaw Sensor with Vehicle Lateral Accelerometer Replacement (See: Brakes and Traction Control/Antilock Brakes / Traction

Control Systems/Yaw Rate Sensor/Service and Repair/Less than 3900 kg (8600 lb) GVW) for the ABS - Non-Hybrid Less than 3900 kg

(8600 lb) GVW

* Vehicle Yaw Sensor with Vehicle Lateral Accelerometer Replacement (See: Brakes and Traction Control/Antilock Brakes / Traction

Control Systems/Yaw Rate Sensor/Service and Repair/Less than 3900 kg (8600 lb) GVW) for the ABS - Non-Hybrid Greater than/Equal to

3900 kg (8600 lb) GVW

* Control Module References (See: Testing and Inspection/Programming and Relearning) for module replacement, setup, and programming

U2169

DTC U2105-U2199

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System

Check - Vehicle) prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an

overview of the diagnostic approach.

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3131

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3131

DTC Descriptor

DTC U2142 00

- Lost Communication With Yaw Rate Sensor (YRS)

Circuit/System Description

Modules connected to the CAN bus serial data circuits monitor for serial data communications during normal vehicle operation. Operating

information and commands are exchanged among the modules. The modules have prerecorded information about what messages are needed to be

exchanged on the serial data circuits. The messages are supervised and also, some periodic messages are used by the receiver module as an

availability indication of the transmitter module. Each message contains the identification number of the transmitter module.

The electronic brake control module (EBCM) activates the other modules connected to the CAN serial data circuits by applying voltage when the

ignition key is in ACC, ON or START. The EBCM, Yaw Rate and Lateral Acceleration Sensor are the only modules connected to the CAN bus

serial data circuits. For more information on CAN bus serial data refer to Data Link Communications Description and Operation (See: Powertrain

Management/Computers and Control Systems/Information Bus/Description and Operation).

Conditions for Running the DTC

* The system voltage is between 9-16 volts.

* The vehicle power mode master requires serial data communication to occur.

Conditions for Setting the DTC

A supervised periodic message that includes the transmitter module availability has not been received.

Action Taken When the DTC Sets

* The vehicle stability enhancement system (VSES), if equipped, and traction control system (TCS) will not function.

* System OFF lamps will illuminate for these systems.

Conditions for Clearing the DTC

* A current DTC clears when the malfunction is no longer present.

* A history DTC clears when the module ignition cycle counter reaches the reset threshold of 50, without a repeat of the malfunction.

Diagnostic Aids

* Sometimes, while diagnosing a specific customer concern or after a repair, you may notice a history U-code present. However, there is no

associated "current" or "active" status. Loss-of- communication U-codes such as these can set for a variety of reasons. Many times, they are

transparent to the vehicle operator and technician, and/or have no associated symptoms. Eventually, they will erase themselves automatically

after a number of fault-free ignition cycles. This condition would most likely be attributed to one of these scenarios:

- A control module on the data communication circuit was disconnected while the communication circuit is awake.

- Power to one or more modules was interrupted during diagnosis.

- A low battery condition was present, so some control modules stop communicating when battery voltage drops below a certain threshold.

- Battery power was restored to the vehicle and control modules on the communication circuit did not all re-initialize at the same time.

- If a loss-of-communication U-code appears in history for no apparent reason, it is most likely associated with one of the scenarios above.

These are all temporary conditions and should never be interpreted as an intermittent fault, causing you to replace a part.

* A control module may have a U-code stored in history that does not require any repairs. Issues with late or corrupted messages between

control modules can be temporary with no apparent symptom or complaint; this does not mean the control module is faulty. Do not replace a

control module based only on a history U-code.

* Do not replace a control module reporting a U-code. The U-code identifies which control module needs to be diagnosed for a communication

issue.

* Communication may be available between the BCM and the scan tool with either the low or high speed GMLAN serial data system

inoperative. This condition is due to the BCM using both the low and high speed GMLAN systems.

* Use to determine if the module uses high or low speed GMLAN serial data communications.

* Some control modules may not have internal protection for specific control circuits and may open a B+ or ignition fuse. If a fuse is open and

the B+ or ignition circuit is not shorted to ground, ensure none of the control circuits are shorted to ground before replacing the control

module.

* This diagnostic can be used for any control module that is not communicating, regardless of the type of serial data circuit it is connected to,

providing the vehicle is equipped with the control module.

Reference Information

Schematic Reference

* Data Communication Schematics (See: Powertrain Management/Computers and Control Systems/Information Bus/Diagrams/Electrical

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3130

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3130

Diagrams) for the ABS - Non-Hybrid Less than 3900 kg (8600 lb) GVW

* Antilock Brake System Schematics (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Diagrams/Electrical

Diagrams) for the ABS - Non-Hybrid Greater than/Equal to 3900 kg (8600 lb) GVW

Connector End View Reference

Component Connector End Views (See: Diagrams/Connector Views)

Description and Operation

Data Link Communications Description and Operation (See: Powertrain Management/Computers and Control Systems/Information

Bus/Description and Operation)

Electrical Information Reference

* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit

Testing/Circuit Testing)

* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Connector Repairs/Connector Repairs)

* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General

Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)

* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring

Repairs/Wiring Repairs)

Scan Tool Reference

Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector of the yaw rate sensor.

2. Ignition ON, verify that a test lamp illuminates between the module voltage circuit and ground.

瀚慖f the test lamp does not illuminate, test the circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the

EBCM.

3. Ignition OFF, test for less than 5 ohms between the module ground circuits and ground.

瀚慖f greater than the specified value, test the ground circuit for an open/high resistance. If the circuit tests normal, replace the EBCM.

4. If all circuits test normal, replace the yaw rate sensor.

Repair Instructions

Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.

* GMLAN Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Wiring Repairs/GMLAN Wiring Repairs)

* ABS Description and Operation (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Description and

Operation/ABS Description and Operation) for the ABS - Hybrid

* Vehicle Yaw Sensor with Vehicle Lateral Accelerometer Replacement (See: Brakes and Traction Control/Antilock Brakes / Traction

Control Systems/Yaw Rate Sensor/Service and Repair/Less than 3900 kg (8600 lb) GVW) for the ABS - Non-Hybrid Less than 3900 kg

(8600 lb) GVW

* Vehicle Yaw Sensor with Vehicle Lateral Accelerometer Replacement (See: Brakes and Traction Control/Antilock Brakes / Traction

Control Systems/Yaw Rate Sensor/Service and Repair/Less than 3900 kg (8600 lb) GVW) for the ABS - Non-Hybrid Greater than/Equal to

3900 kg (8600 lb) GVW

* Control Module References (See: Testing and Inspection/Programming and Relearning) for module replacement, setup, and programming

U2168

DTC U2105-U2199

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System

Check - Vehicle) prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an

overview of the diagnostic approach.

* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure

Instructions) provides an overview of each diagnostic category.

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3129

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3129

DTC U2142 00

- Lost Communication With Yaw Rate Sensor (YRS)

Circuit/System Description

Modules connected to the CAN bus serial data circuits monitor for serial data communications during normal vehicle operation. Operating

information and commands are exchanged among the modules. The modules have prerecorded information about what messages are needed to be

exchanged on the serial data circuits. The messages are supervised and also, some periodic messages are used by the receiver module as an

availability indication of the transmitter module. Each message contains the identification number of the transmitter module.

The electronic brake control module (EBCM) activates the other modules connected to the CAN serial data circuits by applying voltage when the

ignition key is in ACC, ON or START. The EBCM, Yaw Rate and Lateral Acceleration Sensor are the only modules connected to the CAN bus

serial data circuits. For more information on CAN bus serial data refer to Data Link Communications Description and Operation (See: Powertrain

Management/Computers and Control Systems/Information Bus/Description and Operation).

Conditions for Running the DTC

* The system voltage is between 9-16 volts.

* The vehicle power mode master requires serial data communication to occur.

Conditions for Setting the DTC

A supervised periodic message that includes the transmitter module availability has not been received.

Action Taken When the DTC Sets

* The vehicle stability enhancement system (VSES), if equipped, and traction control system (TCS) will not function.

* System OFF lamps will illuminate for these systems.

Conditions for Clearing the DTC

* A current DTC clears when the malfunction is no longer present.

* A history DTC clears when the module ignition cycle counter reaches the reset threshold of 50, without a repeat of the malfunction.

Diagnostic Aids

* Sometimes, while diagnosing a specific customer concern or after a repair, you may notice a history U-code present. However, there is no

associated "current" or "active" status. Loss-of- communication U-codes such as these can set for a variety of reasons. Many times, they are

transparent to the vehicle operator and technician, and/or have no associated symptoms. Eventually, they will erase themselves automatically

after a number of fault-free ignition cycles. This condition would most likely be attributed to one of these scenarios:

- A control module on the data communication circuit was disconnected while the communication circuit is awake.

- Power to one or more modules was interrupted during diagnosis.

- A low battery condition was present, so some control modules stop communicating when battery voltage drops below a certain threshold.

- Battery power was restored to the vehicle and control modules on the communication circuit did not all re-initialize at the same time.

- If a loss-of-communication U-code appears in history for no apparent reason, it is most likely associated with one of the scenarios above.

These are all temporary conditions and should never be interpreted as an intermittent fault, causing you to replace a part.

* A control module may have a U-code stored in history that does not require any repairs. Issues with late or corrupted messages between

control modules can be temporary with no apparent symptom or complaint; this does not mean the control module is faulty. Do not replace a

control module based only on a history U-code.

* Do not replace a control module reporting a U-code. The U-code identifies which control module needs to be diagnosed for a communication

issue.

* Communication may be available between the BCM and the scan tool with either the low or high speed GMLAN serial data system

inoperative. This condition is due to the BCM using both the low and high speed GMLAN systems.

* Use to determine if the module uses high or low speed GMLAN serial data communications.

* Some control modules may not have internal protection for specific control circuits and may open a B+ or ignition fuse. If a fuse is open and

the B+ or ignition circuit is not shorted to ground, ensure none of the control circuits are shorted to ground before replacing the control

module.

* This diagnostic can be used for any control module that is not communicating, regardless of the type of serial data circuit it is connected to,

providing the vehicle is equipped with the control module.

Reference Information

Schematic Reference

* Data Communication Schematics (See: Powertrain Management/Computers and Control Systems/Information Bus/Diagrams/Electrical

Diagrams)

* Antilock Brake System Schematics (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Diagrams/Electrical

Diagrams) for the ABS - Hybrid

* Antilock Brake System Schematics (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Diagrams/Electrical

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3128

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3128

Diagrams) for the ABS - Non-Hybrid Greater than/Equal to 3900 kg (8600 lb) GVW

Connector End View Reference

Component Connector End Views (See: Diagrams/Connector Views)

Description and Operation

Data Link Communications Description and Operation (See: Powertrain Management/Computers and Control Systems/Information

Bus/Description and Operation)

Electrical Information Reference

* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit

Testing/Circuit Testing)

* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Connector Repairs/Connector Repairs)

* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General

Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)

* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring

Repairs/Wiring Repairs)

Scan Tool Reference

Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector of the yaw rate sensor.

2. Ignition ON, verify that a test lamp illuminates between the module voltage circuit and ground.

瀚慖f the test lamp does not illuminate, test the circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the

EBCM.

3. Ignition OFF, test for less than 5 ohms between the module ground circuits and ground.

瀚慖f greater than the specified value, test the ground circuit for an open/high resistance. If the circuit tests normal, replace the EBCM.

4. If all circuits test normal, replace the yaw rate sensor.

Repair Instructions

Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.

* GMLAN Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Wiring Repairs/GMLAN Wiring Repairs)

* ABS Description and Operation (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Description and

Operation/ABS Description and Operation) for the ABS - Hybrid

* Vehicle Yaw Sensor with Vehicle Lateral Accelerometer Replacement (See: Brakes and Traction Control/Antilock Brakes / Traction

Control Systems/Yaw Rate Sensor/Service and Repair/Less than 3900 kg (8600 lb) GVW) for the ABS - Non-Hybrid Less than 3900 kg

(8600 lb) GVW

* Vehicle Yaw Sensor with Vehicle Lateral Accelerometer Replacement (See: Brakes and Traction Control/Antilock Brakes / Traction

Control Systems/Yaw Rate Sensor/Service and Repair/Less than 3900 kg (8600 lb) GVW) for the ABS - Non-Hybrid Greater than/Equal to

3900 kg (8600 lb) GVW

* Control Module References (See: Testing and Inspection/Programming and Relearning) for module replacement, setup, and programming

U2167

DTC U2105-U2199

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System

Check - Vehicle) prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an

overview of the diagnostic approach.

* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure

Instructions) provides an overview of each diagnostic category.

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3127

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3127

Circuit/System Description

Modules connected to the CAN bus serial data circuits monitor for serial data communications during normal vehicle operation. Operating

information and commands are exchanged among the modules. The modules have prerecorded information about what messages are needed to be

exchanged on the serial data circuits. The messages are supervised and also, some periodic messages are used by the receiver module as an

availability indication of the transmitter module. Each message contains the identification number of the transmitter module.

The electronic brake control module (EBCM) activates the other modules connected to the CAN serial data circuits by applying voltage when the

ignition key is in ACC, ON or START. The EBCM, Yaw Rate and Lateral Acceleration Sensor are the only modules connected to the CAN bus

serial data circuits. For more information on CAN bus serial data refer to Data Link Communications Description and Operation (See: Powertrain

Management/Computers and Control Systems/Information Bus/Description and Operation).

Conditions for Running the DTC

* The system voltage is between 9-16 volts.

* The vehicle power mode master requires serial data communication to occur.

Conditions for Setting the DTC

A supervised periodic message that includes the transmitter module availability has not been received.

Action Taken When the DTC Sets

* The vehicle stability enhancement system (VSES), if equipped, and traction control system (TCS) will not function.

* System OFF lamps will illuminate for these systems.

Conditions for Clearing the DTC

* A current DTC clears when the malfunction is no longer present.

* A history DTC clears when the module ignition cycle counter reaches the reset threshold of 50, without a repeat of the malfunction.

Diagnostic Aids

* Sometimes, while diagnosing a specific customer concern or after a repair, you may notice a history U-code present. However, there is no

associated "current" or "active" status. Loss-of- communication U-codes such as these can set for a variety of reasons. Many times, they are

transparent to the vehicle operator and technician, and/or have no associated symptoms. Eventually, they will erase themselves automatically

after a number of fault-free ignition cycles. This condition would most likely be attributed to one of these scenarios:

- A control module on the data communication circuit was disconnected while the communication circuit is awake.

- Power to one or more modules was interrupted during diagnosis.

- A low battery condition was present, so some control modules stop communicating when battery voltage drops below a certain threshold.

- Battery power was restored to the vehicle and control modules on the communication circuit did not all re-initialize at the same time.

- If a loss-of-communication U-code appears in history for no apparent reason, it is most likely associated with one of the scenarios above.

These are all temporary conditions and should never be interpreted as an intermittent fault, causing you to replace a part.

* A control module may have a U-code stored in history that does not require any repairs. Issues with late or corrupted messages between

control modules can be temporary with no apparent symptom or complaint; this does not mean the control module is faulty. Do not replace a

control module based only on a history U-code.

* Do not replace a control module reporting a U-code. The U-code identifies which control module needs to be diagnosed for a communication

issue.

* Communication may be available between the BCM and the scan tool with either the low or high speed GMLAN serial data system

inoperative. This condition is due to the BCM using both the low and high speed GMLAN systems.

* Use to determine if the module uses high or low speed GMLAN serial data communications.

* Some control modules may not have internal protection for specific control circuits and may open a B+ or ignition fuse. If a fuse is open and

the B+ or ignition circuit is not shorted to ground, ensure none of the control circuits are shorted to ground before replacing the control

module.

* This diagnostic can be used for any control module that is not communicating, regardless of the type of serial data circuit it is connected to,

providing the vehicle is equipped with the control module.

Reference Information

Schematic Reference

* Data Communication Schematics (See: Powertrain Management/Computers and Control Systems/Information Bus/Diagrams/Electrical

Diagrams)

* Antilock Brake System Schematics (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Diagrams/Electrical

Diagrams) for the ABS - Hybrid

* Antilock Brake System Schematics (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Diagrams/Electrical

Diagrams) for the ABS - Non-Hybrid Less than 3900 kg (8600 lb) GVW

* Antilock Brake System Schematics (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Diagrams/Electrical

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3126

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3126

Component Connector End Views (See: Diagrams/Connector Views)

Description and Operation

Data Link Communications Description and Operation (See: Powertrain Management/Computers and Control Systems/Information

Bus/Description and Operation)

Electrical Information Reference

* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit

Testing/Circuit Testing)

* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Connector Repairs/Connector Repairs)

* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General

Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)

* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring

Repairs/Wiring Repairs)

Scan Tool Reference

Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector of the yaw rate sensor.

2. Ignition ON, verify that a test lamp illuminates between the module voltage circuit and ground.

瀚慖f the test lamp does not illuminate, test the circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the

EBCM.

3. Ignition OFF, test for less than 5 ohms between the module ground circuits and ground.

瀚慖f greater than the specified value, test the ground circuit for an open/high resistance. If the circuit tests normal, replace the EBCM.

4. If all circuits test normal, replace the yaw rate sensor.

Repair Instructions

Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.

* GMLAN Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Wiring Repairs/GMLAN Wiring Repairs)

* ABS Description and Operation (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Description and

Operation/ABS Description and Operation) for the ABS - Hybrid

* Vehicle Yaw Sensor with Vehicle Lateral Accelerometer Replacement (See: Brakes and Traction Control/Antilock Brakes / Traction

Control Systems/Yaw Rate Sensor/Service and Repair/Less than 3900 kg (8600 lb) GVW) for the ABS - Non-Hybrid Less than 3900 kg

(8600 lb) GVW

* Vehicle Yaw Sensor with Vehicle Lateral Accelerometer Replacement (See: Brakes and Traction Control/Antilock Brakes / Traction

Control Systems/Yaw Rate Sensor/Service and Repair/Less than 3900 kg (8600 lb) GVW) for the ABS - Non-Hybrid Greater than/Equal to

3900 kg (8600 lb) GVW

* Control Module References (See: Testing and Inspection/Programming and Relearning) for module replacement, setup, and programming

U2166

DTC U2105-U2199

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System

Check - Vehicle) prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an

overview of the diagnostic approach.

* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure

Instructions) provides an overview of each diagnostic category.

DTC Descriptor

DTC U2142 00

- Lost Communication With Yaw Rate Sensor (YRS)

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3125

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3125

information and commands are exchanged among the modules. The modules have prerecorded information about what messages are needed to be

exchanged on the serial data circuits. The messages are supervised and also, some periodic messages are used by the receiver module as an

availability indication of the transmitter module. Each message contains the identification number of the transmitter module.

The electronic brake control module (EBCM) activates the other modules connected to the CAN serial data circuits by applying voltage when the

ignition key is in ACC, ON or START. The EBCM, Yaw Rate and Lateral Acceleration Sensor are the only modules connected to the CAN bus

serial data circuits. For more information on CAN bus serial data refer to Data Link Communications Description and Operation (See: Powertrain

Management/Computers and Control Systems/Information Bus/Description and Operation).

Conditions for Running the DTC

* The system voltage is between 9-16 volts.

* The vehicle power mode master requires serial data communication to occur.

Conditions for Setting the DTC

A supervised periodic message that includes the transmitter module availability has not been received.

Action Taken When the DTC Sets

* The vehicle stability enhancement system (VSES), if equipped, and traction control system (TCS) will not function.

* System OFF lamps will illuminate for these systems.

Conditions for Clearing the DTC

* A current DTC clears when the malfunction is no longer present.

* A history DTC clears when the module ignition cycle counter reaches the reset threshold of 50, without a repeat of the malfunction.

Diagnostic Aids

* Sometimes, while diagnosing a specific customer concern or after a repair, you may notice a history U-code present. However, there is no

associated "current" or "active" status. Loss-of- communication U-codes such as these can set for a variety of reasons. Many times, they are

transparent to the vehicle operator and technician, and/or have no associated symptoms. Eventually, they will erase themselves automatically

after a number of fault-free ignition cycles. This condition would most likely be attributed to one of these scenarios:

- A control module on the data communication circuit was disconnected while the communication circuit is awake.

- Power to one or more modules was interrupted during diagnosis.

- A low battery condition was present, so some control modules stop communicating when battery voltage drops below a certain threshold.

- Battery power was restored to the vehicle and control modules on the communication circuit did not all re-initialize at the same time.

- If a loss-of-communication U-code appears in history for no apparent reason, it is most likely associated with one of the scenarios above.

These are all temporary conditions and should never be interpreted as an intermittent fault, causing you to replace a part.

* A control module may have a U-code stored in history that does not require any repairs. Issues with late or corrupted messages between

control modules can be temporary with no apparent symptom or complaint; this does not mean the control module is faulty. Do not replace a

control module based only on a history U-code.

* Do not replace a control module reporting a U-code. The U-code identifies which control module needs to be diagnosed for a communication

issue.

* Communication may be available between the BCM and the scan tool with either the low or high speed GMLAN serial data system

inoperative. This condition is due to the BCM using both the low and high speed GMLAN systems.

* Use to determine if the module uses high or low speed GMLAN serial data communications.

* Some control modules may not have internal protection for specific control circuits and may open a B+ or ignition fuse. If a fuse is open and

the B+ or ignition circuit is not shorted to ground, ensure none of the control circuits are shorted to ground before replacing the control

module.

* This diagnostic can be used for any control module that is not communicating, regardless of the type of serial data circuit it is connected to,

providing the vehicle is equipped with the control module.

Reference Information

Schematic Reference

* Data Communication Schematics (See: Powertrain Management/Computers and Control Systems/Information Bus/Diagrams/Electrical

Diagrams)

* Antilock Brake System Schematics (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Diagrams/Electrical

Diagrams) for the ABS - Hybrid

* Antilock Brake System Schematics (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Diagrams/Electrical

Diagrams) for the ABS - Non-Hybrid Less than 3900 kg (8600 lb) GVW

* Antilock Brake System Schematics (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Diagrams/Electrical

Diagrams) for the ABS - Non-Hybrid Greater than/Equal to 3900 kg (8600 lb) GVW

Connector End View Reference

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3124

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3124

Data Link Communications Description and Operation (See: Powertrain Management/Computers and Control Systems/Information

Bus/Description and Operation)

Electrical Information Reference

* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit

Testing/Circuit Testing)

* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Connector Repairs/Connector Repairs)

* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General

Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)

* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring

Repairs/Wiring Repairs)

Scan Tool Reference

Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector of the yaw rate sensor.

2. Ignition ON, verify that a test lamp illuminates between the module voltage circuit and ground.

瀚慖f the test lamp does not illuminate, test the circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the

EBCM.

3. Ignition OFF, test for less than 5 ohms between the module ground circuits and ground.

瀚慖f greater than the specified value, test the ground circuit for an open/high resistance. If the circuit tests normal, replace the EBCM.

4. If all circuits test normal, replace the yaw rate sensor.

Repair Instructions

Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.

* GMLAN Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Wiring Repairs/GMLAN Wiring Repairs)

* ABS Description and Operation (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Description and

Operation/ABS Description and Operation) for the ABS - Hybrid

* Vehicle Yaw Sensor with Vehicle Lateral Accelerometer Replacement (See: Brakes and Traction Control/Antilock Brakes / Traction

Control Systems/Yaw Rate Sensor/Service and Repair/Less than 3900 kg (8600 lb) GVW) for the ABS - Non-Hybrid Less than 3900 kg

(8600 lb) GVW

* Vehicle Yaw Sensor with Vehicle Lateral Accelerometer Replacement (See: Brakes and Traction Control/Antilock Brakes / Traction

Control Systems/Yaw Rate Sensor/Service and Repair/Less than 3900 kg (8600 lb) GVW) for the ABS - Non-Hybrid Greater than/Equal to

3900 kg (8600 lb) GVW

* Control Module References (See: Testing and Inspection/Programming and Relearning) for module replacement, setup, and programming

U2165

DTC U2105-U2199

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System

Check - Vehicle) prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an

overview of the diagnostic approach.

* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure

Instructions) provides an overview of each diagnostic category.

DTC Descriptor

DTC U2142 00

- Lost Communication With Yaw Rate Sensor (YRS)

Circuit/System Description

Modules connected to the CAN bus serial data circuits monitor for serial data communications during normal vehicle operation. Operating

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3123

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3123

The electronic brake control module (EBCM) activates the other modules connected to the CAN serial data circuits by applying voltage when the

ignition key is in ACC, ON or START. The EBCM, Yaw Rate and Lateral Acceleration Sensor are the only modules connected to the CAN bus

serial data circuits. For more information on CAN bus serial data refer to Data Link Communications Description and Operation (See: Powertrain

Management/Computers and Control Systems/Information Bus/Description and Operation).

Conditions for Running the DTC

* The system voltage is between 9-16 volts.

* The vehicle power mode master requires serial data communication to occur.

Conditions for Setting the DTC

A supervised periodic message that includes the transmitter module availability has not been received.

Action Taken When the DTC Sets

* The vehicle stability enhancement system (VSES), if equipped, and traction control system (TCS) will not function.

* System OFF lamps will illuminate for these systems.

Conditions for Clearing the DTC

* A current DTC clears when the malfunction is no longer present.

* A history DTC clears when the module ignition cycle counter reaches the reset threshold of 50, without a repeat of the malfunction.

Diagnostic Aids

* Sometimes, while diagnosing a specific customer concern or after a repair, you may notice a history U-code present. However, there is no

associated "current" or "active" status. Loss-of- communication U-codes such as these can set for a variety of reasons. Many times, they are

transparent to the vehicle operator and technician, and/or have no associated symptoms. Eventually, they will erase themselves automatically

after a number of fault-free ignition cycles. This condition would most likely be attributed to one of these scenarios:

- A control module on the data communication circuit was disconnected while the communication circuit is awake.

- Power to one or more modules was interrupted during diagnosis.

- A low battery condition was present, so some control modules stop communicating when battery voltage drops below a certain threshold.

- Battery power was restored to the vehicle and control modules on the communication circuit did not all re-initialize at the same time.

- If a loss-of-communication U-code appears in history for no apparent reason, it is most likely associated with one of the scenarios above.

These are all temporary conditions and should never be interpreted as an intermittent fault, causing you to replace a part.

* A control module may have a U-code stored in history that does not require any repairs. Issues with late or corrupted messages between

control modules can be temporary with no apparent symptom or complaint; this does not mean the control module is faulty. Do not replace a

control module based only on a history U-code.

* Do not replace a control module reporting a U-code. The U-code identifies which control module needs to be diagnosed for a communication

issue.

* Communication may be available between the BCM and the scan tool with either the low or high speed GMLAN serial data system

inoperative. This condition is due to the BCM using both the low and high speed GMLAN systems.

* Use to determine if the module uses high or low speed GMLAN serial data communications.

* Some control modules may not have internal protection for specific control circuits and may open a B+ or ignition fuse. If a fuse is open and

the B+ or ignition circuit is not shorted to ground, ensure none of the control circuits are shorted to ground before replacing the control

module.

* This diagnostic can be used for any control module that is not communicating, regardless of the type of serial data circuit it is connected to,

providing the vehicle is equipped with the control module.

Reference Information

Schematic Reference

* Data Communication Schematics (See: Powertrain Management/Computers and Control Systems/Information Bus/Diagrams/Electrical

Diagrams)

* Antilock Brake System Schematics (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Diagrams/Electrical

Diagrams) for the ABS - Hybrid

* Antilock Brake System Schematics (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Diagrams/Electrical

Diagrams) for the ABS - Non-Hybrid Less than 3900 kg (8600 lb) GVW

* Antilock Brake System Schematics (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Diagrams/Electrical

Diagrams) for the ABS - Non-Hybrid Greater than/Equal to 3900 kg (8600 lb) GVW

Connector End View Reference

Component Connector End Views (See: Diagrams/Connector Views)

Description and Operation