2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 945

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 945

* 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 C056D XX

- Electronic Control Unit Hardware

Circuit/System Description

The internal fault detection is handled inside the control module. The symptom byte listed in the DTC Descriptor is for engineering reference only.

No external circuit diagnosis is involved.

Conditions for Running the DTC

The module runs the program to detect an internal fault when power up is commanded. The only requirements are voltage and ground. This

program runs even if the voltage is out of the valid operating range.

Conditions for Setting the DTC

The module has detected an internal malfunction.

Action Taken When the DTC Sets

The module refuses all additional inputs.

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

* This DTC may be stored as a history DTC without affecting the operation of the module.

* If stored only as a history DTC and not retrieved as a current DTC, do not replace the module.

* If this DTC is retrieved as both a current and history DTC, replace the module that set the DTC.

Circuit/System Verification

Verify that DTC C056D is not set.

If the DTC is set, program the control module. If the DTC resets, replace the control module that set the DTC.

Repair Instructions

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

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

Power Steering

DTC C056D

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) provide an overview of each diagnostic category.

DTC Descriptor

DTC C056D 39

- ECU Hardware Performance Internal Electronic Failure

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 823

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 823

* 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) provide an overview of each diagnostic category.

DTC Descriptors

DTC C056D 00

- ECU Hardware Performance

DTC C056D 3C

- ECU Hardware Performance Internal Communications Failure

DTC C056D 59

- ECU Hardware Performance

DTC C120C

- Brake Pedal Position Sensor 4 Plausibility

DTC C121C

- EBCM Internal Communication Error

DTC C121E

- EBCM Unimplemented Interrupt

DTC C121F

- EBCM Unexpected Exception

DTC C123A

- EBCM High End Timer Watchdog

DTC C123B

- EBCM High End Timer Program Overflow

DTC C123C

- EBCM High End Timer RAM Fault

DTC C123D

- EBCM Solenoid Timeout

DTC C123E

- EBCM High End Timer Periodic Interrupt

DTC C123F

- EBCM Serial Peripheral Interface Inoperative

DTC C1255

- Electronic Control Unit Performance

DTC C1256

- Program ROM Checksum Error

DTC C126E

- EBCM Stack Overrun

DTC C126F

- EBCM Serial Peripheral Interface Performance

DTC C127C

- EBCM Self Test Failed

DTC C127E

- EBCM Module High Temperature

DTC C12A7

- ABS Boost Valve Solenoid Circuit Performance

DTC C12C2

- ABS Left Front Isolation Solenoid Valve Driver Shorted

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 813

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 813

* 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) provide an overview of each diagnostic category.

DTC Descriptors

DTC C056D 00

- ECU Hardware Performance

DTC C056D 3C

- ECU Hardware Performance Internal Communications Failure

DTC C056D 59

- ECU Hardware Performance

DTC C120C

- Brake Pedal Position Sensor 4 Plausibility

DTC C121C

- EBCM Internal Communication Error

DTC C121E

- EBCM Unimplemented Interrupt

DTC C121F

- EBCM Unexpected Exception

DTC C123A

- EBCM High End Timer Watchdog

DTC C123B

- EBCM High End Timer Program Overflow

DTC C123C

- EBCM High End Timer RAM Fault

DTC C123D

- EBCM Solenoid Timeout

DTC C123E

- EBCM High End Timer Periodic Interrupt

DTC C123F

- EBCM Serial Peripheral Interface Inoperative

DTC C1255

- Electronic Control Unit Performance

DTC C1256

- Program ROM Checksum Error

DTC C126E

- EBCM Stack Overrun

DTC C126F

- EBCM Serial Peripheral Interface Performance

DTC C127C

- EBCM Self Test Failed

DTC C127E

- EBCM Module High Temperature

DTC C12A7

- ABS Boost Valve Solenoid Circuit Performance

DTC C12C2

- ABS Left Front Isolation Solenoid Valve Driver Shorted

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 803

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 803

* 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) provide an overview of each diagnostic category.

DTC Descriptors

DTC C056D 00

- ECU Hardware Performance

DTC C056D 3C

- ECU Hardware Performance Internal Communications Failure

DTC C056D 59

- ECU Hardware Performance

DTC C120C

- Brake Pedal Position Sensor 4 Plausibility

DTC C121C

- EBCM Internal Communication Error

DTC C121E

- EBCM Unimplemented Interrupt

DTC C121F

- EBCM Unexpected Exception

DTC C123A

- EBCM High End Timer Watchdog

DTC C123B

- EBCM High End Timer Program Overflow

DTC C123C

- EBCM High End Timer RAM Fault

DTC C123D

- EBCM Solenoid Timeout

DTC C123E

- EBCM High End Timer Periodic Interrupt

DTC C123F

- EBCM Serial Peripheral Interface Inoperative

DTC C1255

- Electronic Control Unit Performance

DTC C1256

- Program ROM Checksum Error

DTC C126E

- EBCM Stack Overrun

DTC C126F

- EBCM Serial Peripheral Interface Performance

DTC C127C

- EBCM Self Test Failed

DTC C127E

- EBCM Module High Temperature

DTC C12A7

- ABS Boost Valve Solenoid Circuit Performance

DTC C12C2

- ABS Left Front Isolation Solenoid Valve Driver Shorted

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 747

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 747

* 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 B3894 5A

- Stop Lamp Switch Circuit Plausibility Failure

Circuit/System Description

The brake switch is hard wired to the fuel pump/trailer brake control module. The body control module (BCM) sends a brake switch status serial

data message to the fuel pump/trailer brake control module. The fuel pump/trailer brake control module compares the states of the brake switch

signal to the serial data message after a master cylinder brake pressure sensor threshold is exceeded. If the brake switch signal and the serial data

message are not in agreement or if the serial data message is not valid, a DTC will set and the trailer brake control system will be disabled.

Conditions for Running the DTC

* Battery voltage is 9.5-17 V.

* The module initialization has taken place.

* The master cylinder brake pressure exceeds threshold

Conditions for Setting the DTC

* The brake switch serial data message is not valid.

* The actual brake switch input to the fuel pump/trailer brake control module, and the serial data information for the brake switch do not match.

Action Taken When the DTC Sets

* The trailer brake control will be disabled for the remainder of the ignition cycle.

* The driver information center (DIC) will display Service Trailer Brake System.

Conditions for Clearing the DTC

* The condition for the DTC is no longer present.

* The fuel pump/trailer brake control module clears the history DTC when a current DTC is not detected in 40 consecutive drive cycles.

Reference Information

Schematic Reference

Trailer Brake Control Schematics (See: Brakes and Traction Control/Diagrams/Electrical Diagrams)

Connector End View Reference

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

Description and Operation

Trailer Brake Controls Description and Operation (See: Powertrain Management/Computers and Control Systems/Description and

Operation/Trailer Brake Controls 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 Verification

Ignition ON, press the brake pedal. The brake lights should illuminate and the Brake Switch Status parameter should indicate ON.

Circuit/System Testing

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 557

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 557

* 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 Descriptors

DTC B2425 04

- Left Seat Heater Cushion Circuit Open

DTC B2425 0A

- Left Seat Heater Cushion Circuit Rate of Change Below Threshold

DTC B2425 0B

- Left Seat Heater Cushion Circuit Current Above Threshold

DTC B2425 0C

- Left Seat Heater Cushion Circuit Current Below Threshold

DTC B2425 0D

- Left Seat Heater Cushion Circuit Resistance Above Threshold

DTC B2425 0E

- Left Seat Heater Cushion Circuit Resistance Below Threshold

DTC B2425 1F

- Left Seat Heater Cushion Circuit Intermittent

DTC B2430 04

- Right Seat Heater Cushion Circuit Open

DTC B2430 0A

- Right Seat Heater Cushion Circuit Rate of Change Below Threshold

DTC B2430 0B

- Right Seat Heater Cushion Circuit Current Above Threshold

DTC B2430 0C

- Right Seat Heater Cushion Circuit Current Below Threshold

DTC B2430 0D

- Right Seat Heater Cushion Circuit Resistance Above Threshold

DTC B2430 0E

- Right Seat Heater Cushion Circuit Resistance Below Threshold

DTC B2430 1F

- Right Seat Heater Cushion Circuit Intermittent

Diagnostic Fault Information

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 471

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 471

* 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 Descriptors

DTC B1529 03

- Device Voltage Reference Output Circuit Voltage Below Threshold

DTC B1529 07

- Device Voltage Reference Output Circuit Voltage Above Threshold

Diagnostic Fault Information

Circuit/System Description

The body control module (BCM) supplies voltage to the audio steering wheel control switches and monitors the return signal. Each switch state is

associated to a set resistance value and when pressed a specific voltage drop occurs across the resistor unique to the switch. The BCM identifies the

switch selection and activates the feature.

Conditions for Running the DTC

* Battery voltage is between 9-16 volts

* The ignition is ON.

Conditions for Setting the DTC

B1529 03

* The BCM detects a short to ground in the B+ voltage reference circuit.

* The above condition is present for greater than 30 seconds.

B1529 07

* The BCM detects a short to voltage in the B+ voltage reference circuit.

* The above condition is present for greater than 30 seconds.

Action Taken When the DTC Sets

The BCM will ignore switch inputs.

Conditions for Clearing the DTC

* The condition responsible for setting the DTC no longer exists.

* A history DTC will clear once 100 consecutive malfunction free ignition cycles have occurred.

Reference Information

Schematic Reference

Steering Wheel Secondary/Configurable Control Schematics (See: Accessories and Optional Equipment/Diagrams/Electrical Diagrams/Steering

Wheel Secondary/Configurable Control Schematics)

Connector End View Reference

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

Description and Operation

Steering Wheel Controls Description and Operation (See: Accessories and Optional Equipment/Description and Operation/Steering Wheel

Controls 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

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 194

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 194

* 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 Descriptors

DTC B0052 00

- Deployment Commanded

Circuit/System Description

The inflatable restraint sensing and diagnostic module (SDM) contains a device that converts vehicle velocity changes into an electrical signal. The

SDM compares this electrical signal to a value stored in memory. When the generated signal exceeds the stored value, the SDM performs additional

signal processing and compares the generated signals to values stored in memory. When 2 of the generated signals exceed the stored values, the

SDM will cause current to flow through the deployment loops, deploying the air bags and/or pretensioners causing DTC B0052 to set.

Conditions for Running the DTC

Ignition voltage is between 9-16 volts.

Conditions for Setting the DTC

B0052

* The SDM detects a frontal impact of sufficient force to warrant deployment of the frontal modules.

* The SDM detects a side impact of sufficient force to warrant deployment of a side impact module and/or roof rail module.

* The SDM has deployed the seat belt pretensioner for 3 separate deployments.

Action Taken When the DTC Sets

* The SDM requests the instrument panel cluster (IPC) to illuminate the Service Air Bag indicator.

* The SDM records crash data.

Conditions for Clearing the DTC

After an air bag deployment or 3 separate pretensioner deployments the DTC becomes latched and cannot be cleared.

Reference Information

Schematic Reference

SIR Schematics (See: Diagrams/Electrical Diagrams/Air Bag Systems)

Connector End View Reference

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

Description and Operation

SIR System Description and Operation (See: Restraints and Safety Systems/Air Bag Systems/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 Verification

Important: The seat belt pretensioners may deploy for impacts that are not severe enough to warrant frontal or side air bag deployment.

The SDM is capable of sustaining 3 pretensioner deployment events, or one frontal or side deployment event. After the maximum number

of deployments has occurred, DTC B0052 sets and becomes a latched code, which cannot be cleared.

1. Ignition OFF, verify no signs of inflator module or pretensioner deployment exist.