2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 660

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 660

Action Taken When the DTC Sets

* The tilt motor will be deactivated.

* Memory recall functions will be disabled.

Conditions for Clearing the DTC

* A current DTC will clear when the failed switch input is no longer active.

* A history DTC will clear after 100 ignition cycles.

Diagnostic Aids

An intermittently stuck tilt switch may cause a DTC to set.

Reference Information

Schematic Reference

Steering Wheel Schematics (See: Diagrams/Electrical Diagrams/Steering/Steering Column/Steering Wheel Schematics)

Connector End View Reference

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

Description and Operation

Steering Wheel and Column Description and Operation (See: Steering and Suspension/Steering/Steering Column/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,observe the scan tool Tilt Up Switch parameter and Tilt Down Switch parameter while cycling the switch between states.The reading

should be Inactive and change to Active when pushing the appropriate switch.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the tilt switch.

2. Ignition ON, verify a test lamp illuminates between the B+ circuit terminal B and ground.

瀚慖f the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.

3. Verify the scan tool tilt switch parameter is Inactive.

瀚慖f not the specified value, test the control circuit listed below for a short to voltage. If the circuit tests normal, replace the MSM.

* Tilt Up Switch terminal C

* Tilt Down Switch terminal A

4. Install a 3A fused jumper wire between the control circuits listed below and the B+ circuit terminal. Verify the scan tool tilt switch parameter

is Active.

* Tilt Up Switch terminal C

* Tilt Down Switch terminal A

瀚慖f not the specified value, test the appropriate control circuit for a short to ground or an open/high resistance. If the circuit tests normal,

replace the MSM.

5. If all circuit test normal, test or replace the tilt switch.

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 613

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 613

Action Taken When the DTC Sets

The heated seat function for both seats will be disabled.

Conditions for Clearing the DTC

* The current DTC clears when the malfunction is no longer present and the power mode changes to OFF then back to ACC or RUN.

* The history DTC will clear after 50 consecutive fault-free ignition cycles have occurred.

Reference Information

Schematic Reference

Heated/Cooled Seat Schematics ()

Connector End View Reference

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

Description and Operation

Heated Seats Description and Operation (KA1) ()Heated Seats Description and Operation (KA6) ()

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

B2508 02

1. Ignition OFF, disconnect the X1 harness connector at the HSM.

2. Test for infinite resistance between the control circuit terminal 3 and ground.

瀚慖f not the specified value, test the control circuits listed below for a short to ground:

* Driver seat cushion and back element terminal 3

* Driver seat cushion element terminal 5

* Driver seat back element terminal 1

3. Test for infinite resistance between the control circuit terminal 6 and ground.

瀚慖f not the specified value, test the control circuits listed below for a short to ground:

* Passenger seat cushion and back element terminal 6

* Passenger seat cushion element terminal 2

* Passenger seat back element terminal 4

4. If all circuits test normal, replace the HSM.

B2508 01

1. Ignition OFF, disconnect the X1 harness connector at the HSM.

2. Ignition ON, verify that a test lamp does not illuminate between the control circuit terminal 3 and ground.

瀚慖f the test lamp illuminates, test the control circuits listed below for a short to voltage:

* Driver seat cushion and back element terminal 3

* Driver seat cushion element terminal 5

* Driver seat back element terminal 1

3. Verify that a test lamp does not illuminate between the control circuit terminal 6 and ground.

瀚慖f the test lamp illuminates, test the control circuits listed below for a short to voltage:

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 574

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 574

Action Taken When the DTC Sets

The heated seat cushion function for the affected seat will be disabled.

Conditions for Clearing the DTC

* The current DTC clears when the malfunction is no longer present, and the power mode changes to OFF then back to ACC or RUN.

* The history DTC will clear after 50 consecutive fault-free ignition cycles have occurred.

Reference Information

Schematic Reference

Heated/Cooled Seat Schematics ()

Connector End View Reference

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

Description and Operation

Heated Seats Description and Operation (KA1) ()Heated Seats Description and Operation (KA6) ()

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

B2425 0A, B2425 0B, B2425 0C, B2425 0D, B2425 0E, B2425 04, or B2425 1F

1. Ignition OFF, disconnect the X1 harness connector at the HSM.

Important: Element resistance must be measured twice to ensure that all failure conditions are simulated. First with the seat

unoccupied, then with the seat occupied.

2. Test for 2.0 - 8.0 Ohms between control circuit terminal 3 and control circuit terminal 5.

瀚慖f less than the specified range, test for a short between the control circuits. If the circuits test normal, replace the seat cushion heater

element.

瀚慖f greater than the specified range, test the control circuits for an open/high resistance. If the circuits test normal replace the seat cushion

heater element.

3. Disconnect the X2, X4 harness connectors at the HSM.

4. Test for 850 Ohms - 300 kOhms between the signal circuit terminal 9 X4 and the low reference circuit terminal 6 X2.

瀚慖f less than the specified range, test for a short between the signal and low reference circuits. If the circuits test normal, replace the seat

cushion heater element/temperature sensor.

瀚慖f greater than the specified range, test the signal and low reference circuits for a short to voltage or an open/high resistance. If the circuits

test normal, replace the seat cushion heater element/temperature sensor.

5. Connect the X1, X2, X4 harness connectors at the HSM.

6. Disconnect the harness connector at the seat cushion heater element/temperature sensor.

7. Ignition ON, test for 4.8 - 5.2 V between the signal circuit terminal C and ground.

瀚慖f greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the HSM.

瀚慖f less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace

the HSM.

8. If all circuits test normal, replace the HSM.

B2430 0A, B2430 0B, B2430 0C, B2430 0D, B2430 0E, B2430 04, or B2430 1F

1. Ignition OFF, disconnect the X1 harness connector at the HSM.

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 570

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 570

Action Taken When the DTC Sets

The heated seat cushion function for the affected seat will be disabled.

Conditions for Clearing the DTC

* The current DTC clears when the malfunction is no longer present, and the power mode changes to OFF then back to ACC or RUN.

* The history DTC will clear after 50 consecutive fault-free ignition cycles have occurred.

Reference Information

Schematic Reference

Heated/Cooled Seat Schematics ()

Connector End View Reference

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

Description and Operation

Heated Seats Description and Operation (KA1) ()Heated Seats Description and Operation (KA6) ()

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

Verify the type of vehicle and the heated seat system for which the DTC set.

If the DTC set in a hybrid vehicle without memory, refer to Circuit/System Testing below.

If the DTC set in a vehicle equipped with memory, refer to DTC B2425 or B2430 (w/o HP2 with memory).

If the DTC set in a non-hybrid vehicle without memory, refer to DTC B2425 or B2430 (Dealer installed).

If the DTC set in the rear heated seat module, refer to DTC B2425 or B2430 (Rear seat).

Circuit/System Testing

B2425 0A, B2425 0B, B2425 0C, B2425 0D, B2425 0E, B2425 04, or B2425 1F

1. Ignition OFF, disconnect the X1 harness connector at the HSM.

Important: Element resistance must be measured twice to ensure that all failure conditions are simulated. First with the seat

unoccupied, then with the seat occupied.

2. Test for 2.0 - 8.0 Ohms between control circuit terminal 6 and control circuit terminal 5.

瀚慖f less than the specified range, test for a short between the control circuits. If the circuits test normal, replace the seat cushion heater

element.

瀚慖f greater than the specified range, test the control circuits for an open/high resistance. If the circuits test normal replace the seat cushion

heater element.

3. Disconnect the X2, X4 harness connectors at the HSM.

4. Test for 850 - 300 kOhms between the signal circuit terminal 9 X4 and the low reference circuit terminal 6 X2.

瀚慖f less than the specified range, test for a short between the signal and low reference circuits. If the circuits test normal, replace the seat

cushion heater element/temperature sensor.

瀚慖f greater than the specified range, test the signal and low reference circuits for a short to voltage or an open/high resistance. If the circuits

test normal, replace the seat cushion heater element/temperature sensor.

5. Connect the X1, X2, X4 harness connectors at the HSM.

6. Disconnect the harness connector at the seat cushion heater element/temperature sensor.

7. Ignition ON, test for 4.8 - 5.2 V between the signal circuit terminal C and ground.

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 563

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 563

Action Taken When the DTC Sets

The heated seat cushion function for the affected seat will be disabled.

Conditions for Clearing the DTC

* The current DTC clears when the malfunction is no longer present, and the power mode changes to OFF then back to ACC or RUN.

* The history DTC will clear after 50 consecutive fault-free ignition cycles have occurred.

Reference Information

Schematic Reference

Heated/Cooled Seat Schematics ()

Connector End View Reference

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

Description and Operation

Heated Seats Description and Operation (KA1) ()Heated Seats Description and Operation (KA6) ()

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

B2425 0A, B2425 0B, B2425 0C, B2425 0D, B2425 0E, B2425 04, or B2425 1F

1. Ignition OFF, disconnect the X1 harness connector at the HSM.

Important: Element resistance must be measured twice to ensure that all failure conditions are simulated. First with the seat

unoccupied, then with the seat occupied.

2. Test for 2.0 - 8.0 Ohms between control circuit terminal 3 and control circuit terminal 5.

瀚慖f less than the specified range, test for a short between the control circuits. If the circuits test normal, replace the seat cushion heater

element.

瀚慖f greater than the specified range, test the control circuits for an open/high resistance. If the circuits test normal replace the seat cushion

heater element.

3. Disconnect the X2, X4 harness connectors at the HSM.

4. Test for 850 Ohms - 300 kOhms between the signal circuit terminal 9 X4 and the low reference circuit terminal 6 X2.

瀚慖f less than the specified range, test for a short between the signal and low reference circuits. If the circuits test normal, replace the seat

cushion heater element/temperature sensor.

瀚慖f greater than the specified range, test the signal and low reference circuits for a short to voltage or an open/high resistance. If the circuits

test normal, replace the seat cushion heater element/temperature sensor.

5. Connect the X1, X2, X4 harness connectors at the HSM.

6. Disconnect the harness connector at the seat cushion heater element/temperature sensor.

7. Ignition ON, test for 4.8 - 5.2 V between the signal circuit terminal C and ground.

瀚慖f greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the HSM.

瀚慖f less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace

the HSM.

8. If all circuits test normal, replace the HSM.

B2430 0A, B2430 0B, B2430 0C, B2430 0D, B2430 0E, B2430 04, or B2430 1F

1. Ignition OFF, disconnect the X1 harness connector at the HSM.

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 559

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 559

Action Taken When the DTC Sets

The heated seat cushion function for the affected seat will be disabled.

Conditions for Clearing the DTC

* The current DTC clears when the malfunction is no longer present, and the power mode changes to OFF then back to ACC or RUN.

* The history DTC will clear after 50 consecutive fault-free ignition cycles have occurred.

Reference Information

Schematic Reference

Heated/Cooled Seat Schematics ()

Connector End View Reference

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

Description and Operation

Heated Seats Description and Operation (KA1) ()Heated Seats Description and Operation (KA6) ()

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

Verify the type of vehicle and the heated seat system for which the DTC set.

If the DTC set in a hybrid vehicle without memory, refer to Circuit/System Testing below.

If the DTC set in a vehicle equipped with memory, refer to DTC B2425 or B2430 (w/o HP2 with memory).

If the DTC set in a non-hybrid vehicle without memory, refer to DTC B2425 or B2430 (Dealer installed).

If the DTC set in the rear heated seat module, refer to DTC B2425 or B2430 (Rear seat).

Circuit/System Testing

B2425 0A, B2425 0B, B2425 0C, B2425 0D, B2425 0E, B2425 04, or B2425 1F

1. Ignition OFF, disconnect the X1 harness connector at the HSM.

Important: Element resistance must be measured twice to ensure that all failure conditions are simulated. First with the seat

unoccupied, then with the seat occupied.

2. Test for 2.0 - 8.0 Ohms between control circuit terminal 6 and control circuit terminal 5.

瀚慖f less than the specified range, test for a short between the control circuits. If the circuits test normal, replace the seat cushion heater

element.

瀚慖f greater than the specified range, test the control circuits for an open/high resistance. If the circuits test normal replace the seat cushion

heater element.

3. Disconnect the X2, X4 harness connectors at the HSM.

4. Test for 850 - 300 kOhms between the signal circuit terminal 9 X4 and the low reference circuit terminal 6 X2.

瀚慖f less than the specified range, test for a short between the signal and low reference circuits. If the circuits test normal, replace the seat

cushion heater element/temperature sensor.

瀚慖f greater than the specified range, test the signal and low reference circuits for a short to voltage or an open/high resistance. If the circuits

test normal, replace the seat cushion heater element/temperature sensor.

5. Connect the X1, X2, X4 harness connectors at the HSM.

6. Disconnect the harness connector at the seat cushion heater element/temperature sensor.

7. Ignition ON, test for 4.8 - 5.2 V between the signal circuit terminal C and ground.

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 541

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 541

Action Taken When the DTC Sets

The heated seat function for both seats will be disabled.

Conditions for Clearing the DTC

* The current DTC clears when the malfunction is no longer present and the power mode changes to OFF then back to ACC or RUN.

* The history DTC will clear after 50 consecutive fault-free ignition cycles have occurred.

Reference Information

Schematic Reference

Heated/Cooled Seat Schematics ()

Connector End View Reference

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

Description and Operation

Heated Seats Description and Operation (KA1) ()Heated Seats Description and Operation (KA6) ()

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

B2345 00

1. Ignition OFF, disconnect the X1 harness connector at the HSM.

2. Test for infinite resistance between the control circuit terminal 3 and ground.

瀚慖f not the specified value, test the control circuits listed below for a short to ground:

* Driver seat cushion and seat back element terminal 3

* Driver seat cushion element terminal 5

* Driver seat back element terminal 1

3. Test for infinite resistance between the control circuit terminal 6 and ground.

瀚慖f not the specified value, test the control circuits listed below for a short to ground:

* Passenger seat cushion and seat back element terminal 6

* Passenger seat cushion element terminal 2

* Passenger seat back element terminal 4

4. Ignition ON, verify that a test lamp does not illuminate between the control circuit terminal 3 and ground.

瀚慖f the test lamp illuminates, test the control circuits listed below for a short to voltage:

* Driver seat cushion and seat back element terminal 3

* Driver seat cushion element terminal 5

* Driver seat back element terminal 1

5. Verify that a test lamp does not illuminate between the supply voltage circuit terminal 6 and ground.

瀚慖f the test lamp illuminates, test the control circuits listed below for a short to voltage:

* Passenger seat cushion and seat back element terminal 6

* Passenger seat cushion element terminal 2

* Passenger seat back element terminal 4

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 535

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 535

Action Taken When the DTC Sets

The heated seat back function for the affected seat will be disabled.

Conditions for Clearing the DTC

* The current DTC clears when the malfunction is no longer present and the power mode changes to OFF then back to ACC or RUN.

* The history DTC will clear after 50 consecutive fault-free ignition cycles have occurred.

Reference Information

Schematic Reference

Heated/Cooled Seat Schematics ()

Connector End View Reference

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

Description and Operation

Heated Seats Description and Operation (KA1) ()Heated Seats Description and Operation (KA6) ()

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

B1935 0A, B1935 0B, B1935 0C, B1935 0D, B1935 0E, B1935 04, or B1935 1F

1. Ignition OFF, disconnect the X1 harness connector at the HSM.

Important: Element resistance must be measured twice to ensure that all failure conditions are simulated. First with the seat

unoccupied, then with the seat occupied.

2. Test for 3.5 - 11.5 Ohms between control circuit terminal 3 and control circuit terminal 1.

瀚慖f less than the specified range, test for a short between the control circuits. If the circuits test normal, replace the seat back heater

element.

瀚慖f greater than the specified range, test the control circuits for an open/high resistance. If the circuits test normal, replace the seat back

heater element.

3. Disconnect the X2, X4 harness connectors at the HSM.

4. Test for 850 Ohms - 300 kOhms between the signal circuit terminal 19 X4 and the low reference circuit terminal 5 X2.

瀚慖f less than the specified range, test for a short between the signal and low reference circuits. If the circuits test normal, replace the seat

back heater element/temperature sensor.

瀚慖f greater than the specified range, test the signal and low reference circuits for a short to voltage or an open/high resistance. If the circuits

test normal, replace the seat back heater element/temperature sensor.

5. Connect the X1, X2, X4 harness connectors at the HSM.

6. Disconnect the harness connector at the seat back heater element/temperature sensor.

7. Ignition ON, test for 4.8 - 5.2 V between the signal circuit terminal C and ground.

瀚慖f less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace

the HSM.

瀚慖f greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the HSM.

8. If all circuits test normal, replace the HSM.

B2180 0A, B2180 0B, B2180 0C, B2180 0D, B2180 0E, B2180 04, or B2180 1F

1. Ignition OFF, disconnect the X1 harness connector at the HSM.

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 529

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 529

Action Taken When the DTC Sets

The heated seat back function for the affected seat will be disabled.

Conditions for Clearing the DTC

* The current DTC clears when the malfunction is no longer present and the power mode changes to OFF then back to ACC or RUN.

* The history DTC will clear after 50 consecutive fault-free ignition cycles have occurred.

Reference Information

Schematic Reference

Heated/Cooled Seat Schematics ()

Connector End View Reference

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

Description and Operation

Heated Seats Description and Operation (KA1) ()Heated Seats Description and Operation (KA6) ()

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

B1935 0A, B1935 0B, B1935 0C, B1935 0D, B1935 0E, B1935 04, or B1935 1F

1. Ignition OFF, disconnect the X1 harness connector at the HSM.

Important: Element resistance must be measured twice to ensure that all failure conditions are simulated. First with the seat

unoccupied, then with the seat occupied.

2. Test for 3.5 - 11.5 Ohms between control circuit terminal 3 and control circuit terminal 1.

瀚慖f less than the specified range, test for a short between the control circuits. If the circuits test normal, replace the seat back heater

element.

瀚慖f greater than the specified range, test the control circuits for an open/high resistance. If the circuits test normal, replace the seat back

heater element.

3. Disconnect the X2, X4 harness connectors at the HSM.

4. Test for 850 Ohms - 300 kOhms between the signal circuit terminal 19 X4 and the low reference circuit terminal 5 X2.

瀚慖f less than the specified range, test for a short between the signal and low reference circuits. If the circuits test normal, replace the seat

back heater element/temperature sensor.

瀚慖f greater than the specified range, test the signal and low reference circuits for a short to voltage or an open/high resistance. If the circuits

test normal, replace the seat back heater element/temperature sensor.

5. Connect the X1, X2, X4 harness connectors at the HSM.

6. Disconnect the harness connector at the seat back heater element/temperature sensor.

7. Ignition ON, test for 4.8 - 5.2 V between the signal circuit terminal C and ground.

瀚慖f less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace

the HSM.

瀚慖f greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the HSM.

8. If all circuits test normal, replace the HSM.

B2180 0A, B2180 0B, B2180 0C, B2180 0D, B2180 0E, B2180 04, or B2180 1F

1. Ignition OFF, disconnect the X1 harness connector at the HSM.

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 525

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 525

Action Taken When the DTC Sets

The heated seat back function for the affected seat will be disabled.

Conditions for Clearing the DTC

* The current DTC clears when the malfunction is no longer present and the power mode changes to OFF then back to ACC or RUN.

* The history DTC will clear after 50 consecutive fault-free ignition cycles have occurred.

Reference Information

Schematic Reference

Heated/Cooled Seat Schematics ()

Connector End View Reference

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

Description and Operation

Heated Seats Description and Operation (KA1) ()Heated Seats Description and Operation (KA6) ()

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

Verify the type of vehicle and the heated seat system for which the DTC set.

If the DTC set in a hybrid vehicle without memory, refer to Circuit/System Testing below.

If the DTC set in a vehicle equipped with memory, refer to DTC B1935 or B2180 (w/o HP2 with memory).

If the DTC set in a non-hybrid vehicle without memory, refer to DTC B1935 or B2180 (Dealer installed).

Circuit/System Testing

B1935 0A, B1935 0B, B1935 0C, B1935 0D, B1935 0E, B1935 04, or B1935 1F

1. Ignition OFF, disconnect the X1 harness connector at the HSM.

Important: Element resistance must be measured twice to ensure that all failure conditions are simulated. First with the seat

unoccupied, then with the seat occupied.

2. Test for 3.5 - 11.5 Ohms between control circuit terminal 6 and control circuit terminal 1.

瀚慖f less than the specified range, test for a short between the control circuits. If the circuits test normal, replace the seat back heater

element.

瀚慖f greater than the specified range, test the control circuits for an open/high resistance. If the circuits test normal, replace the seat back

heater element.

3. Disconnect the X2, X4 harness connectors at the HSM.

4. Test for 850 Ohms - 300 kOhms between the signal circuit terminal 19 X4 and the low reference circuit terminal 5 X2.

瀚慖f less than the specified range, test for a short between the signal and low reference circuits. If the circuits test normal, replace the seat

back heater element/temperature sensor.

瀚慖f greater than the specified range, test the signal and low reference circuits for a short to voltage or an open/high resistance. If the circuits

test normal, replace the seat back heater element/temperature sensor.

5. Connect the X1, X2, X4 harness connectors at the HSM.

6. Disconnect the harness connector at the seat back heater element/temperature sensor.

7. Ignition ON, test for 4.8 - 5.2 V between the signal circuit terminal C and ground.

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 486

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 486

Action Taken When the DTC Sets

Power folding mirror operations are suspended as long as the fault is present.

Conditions for Clearing the DTC

* A current DTC will clear when the fault is no longer present.

* A history DTC will clear after 40 fault free ignition cycles.

Reference Information

Schematic Reference

Outside Rearview Mirror Schematics (See: Body and Frame/Mirrors/Diagrams/Electrical Diagrams/Outside Rearview Mirror Schematics)

Connector End View Reference

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

Description and Operation

Outside Mirror Description and Operation (Heated Mirrors) (See: Body and Frame/Mirrors/Description and Operation/Outside Mirror Description

and Operation (Heated Mirrors))Outside Mirror Description and Operation (Power Mirrors) (See: Body and Frame/Mirrors/Description and

Operation/Outside Mirror Description and Operation (Power Mirrors))

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 References

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

Circuit/System Verification

Ignition ON, using the folding mirror switch, the left and right rearview mirrors should extend and retract as commanded.

Circuit/System Testing

1. Ignition OFF, disconnect the X7 harness connector at the appropriate door module.

2. Ignition ON, verify a test lamp does not illuminate between the following circuit terminals and ground:

* Control circuit terminal 1

* Control circuit terminal 2

瀚慖f the test lamp illuminates, test the appropriate circuit for a short to voltage.

3. Ignition OFF, test for infinite resistance between the following circuits and ground:

* Control circuit terminal 1

* Control circuit terminal 2

瀚慖f less than the specified value, test the appropriate circuit for a short to ground. If the circuits test normal, test or replace the rearview

mirror.

4. Test for 5-15 ohms between the control circuit terminal 1 and the control circuit terminal 2.

瀚慖f not within the specified range, test both control circuits for an open/high resistance. If the circuits test normal, test or replace the

rearview mirror.

5. If all circuits test normal, replace the appropriate door module.

Repair Instructions

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

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 418

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 418

Action Taken When the DTC Sets

The radio sets the DTC and defaults the video display to normal mode.

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

Video System Schematics (See: Accessories and Optional Equipment/Diagrams/Electrical Diagrams/Video System Schematics)

Connector End View Reference

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

Description and Operation

Video Entertainment System Description and Operation (Non-Headrest DVD Systems) (See: Accessories and Optional Equipment/Description

and Operation/Video Entertainment System Description and Operation (Non-Headrest DVD Systems))Video Entertainment System Description

and Operation (Dual Headrest DVD Systems) (See: Accessories and Optional Equipment/Description and Operation/Video Entertainment System

Description and Operation (Dual Headrest DVD Systems))

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 at the rear video display.

2. Ignition ON, test for 100-300 Hz at the control circuit terminal 10.

瀚慖f not within the specified range, test the control circuit for a short to voltage, short to ground, or an open/high resistance. If the circuit

tests normal, replace the radio.

3. If all circuits test normal, replace the rear video display.

Repair Instructions

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

* Video Display Replacement (Second Row) (See: Accessories and Optional Equipment/Entertainment Systems/Television / Monitor/Service

and Repair/Video Display Replacement (Second Row))Video Display Replacement (Third Row) (See: Accessories and Optional

Equipment/Entertainment Systems/Television / Monitor/Service and Repair/Video Display Replacement (Third Row))

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

B1289

DTC B1289

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.

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2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 407

Action Taken When the DTC Sets

No sound is present from one or more of the speakers.

Conditions for Clearing the DTC

Set by Radio

The fault condition becomes history if not present for 0.25 seconds.

Set by Bose Amplifier

The fault condition becomes history after the vehicle ignition has been OFF for several hours and then the ignition turns ON.

Diagnostic Aids

Speakers located in the front A-pillar are connected to the same channel as the speaker in the door. A DTC will only set after the amplifier only on

up-level radios.

Reference Information

Schematic Reference

Radio/Navigation System Schematics (See: Accessories and Optional Equipment/Diagrams/Electrical Diagrams/Radio/Navigation System

Schematics)

Connector End View Reference

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

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

Radio ON, adjust the fade and balance controls on the radio to test all four channels individually. Each of the four channels should produce clear

and even sound.

Circuit/System Testing

Important: This DTC can be set by either the radio or the amplifier. If the DTC was set by the radio, diagnose the appropriate audio

output circuits to the speakers or the low level inputs to the amplifier (if equipped). If the DTC was set by the amplifier, diagnose audio

output signals to the speakers from the amplifier. If equipped with rear seat audio (RSA) (U42), the RSA must be turned off to perform

proper speaker testing.

Without Amplifier

1. Ignition OFF, disconnect the harness connector at the appropriate speaker.

2. Radio ON, test for 5.0-7.5 volts between the signal circuit terminal A and ground.

瀚慖f greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the radio.

瀚慖f less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace

the radio.

3. Test for 5.0-7.5 volts between the signal circuit terminal B and ground.

瀚慖f greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the radio.

瀚慖f less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace

the radio.

4. If all circuits test normal, replace the speaker.

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2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 361

Action Taken When the DTC Sets

No sound is present from one or more of the speakers.

Conditions for Clearing the DTC

Set by Radio

The fault condition becomes history if not present for 0.25 seconds.

Set by Bose Amplifier

The fault condition becomes history after the vehicle ignition has been OFF for several hours and then the ignition turns ON.

Diagnostic Aids

Speakers located in the front A-pillar are connected to the same channel as the speaker in the door. A DTC will only set after the amplifier only on

up-level radios.

Reference Information

Schematic Reference

Radio/Navigation System Schematics (See: Accessories and Optional Equipment/Diagrams/Electrical Diagrams/Radio/Navigation System

Schematics)

Connector End View Reference

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

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

Radio ON, adjust the fade and balance controls on the radio to test all four channels individually. Each of the four channels should produce clear

and even sound.

Circuit/System Testing

Important: This DTC can be set by either the radio or the amplifier. If the DTC was set by the radio, diagnose the appropriate audio

output circuits to the speakers or the low level inputs to the amplifier (if equipped). If the DTC was set by the amplifier, diagnose audio

output signals to the speakers from the amplifier. If equipped with rear seat audio (RSA) (U42), the RSA must be turned off to perform

proper speaker testing.

Without Amplifier

1. Ignition OFF, disconnect the harness connector at the appropriate speaker.

2. Radio ON, test for 5.0-7.5 volts between the signal circuit terminal A and ground.

瀚慖f greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the radio.

瀚慖f less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace

the radio.

3. Test for 5.0-7.5 volts between the signal circuit terminal B and ground.

瀚慖f greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the radio.

瀚慖f less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace

the radio.

4. If all circuits test normal, replace the speaker.

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2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 204

Action Taken When the DTC Sets

* The SDM defaults the seat position sensor to seat forward threshold.

* The SDM requests the instrument panel cluster to illuminate the AIR BAG indicator.

Conditions for Clearing the DTC

* The condition for setting the DTC no longer present.

* A history DTC will clear once 100 fault-free ignition cycles have occurred.

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)

* 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)

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

Procedures/Connector Repairs/Connector Repairs)

Scan Tool Reference

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

Circuit/System Verification

1. Verify that DTC B0079 08 or B0080 08 is not set.

瀚慖f the DTC is set with the symptom byte 08, replace the appropriate B88 seat position sensor.

2. Ignition ON, observe the scan tool seat position sensor parameter. The reading should be between 2-20 m A. With the scan tool verify that

the seat position sensor parameter is between 2-20 m A.

瀚慖f not within the specified range, refer to Circuit/System Testing.

3. With the seat un-weighted, observe the scan tool while moving the seat to the full forward and then full rearward positions. The seat position

sensor parameter should be continuously between 2-20 m A.

瀚慖f not within the specified range, refer to Circuit/System Testing.

4. While sitting in the seat, observe the scan tool while moving the seat to the full forward and then full rearward positions. The seat position

sensor parameter should be continuously between 2-20 m A.

瀚慖f not within the specified range, refer to Circuit/System Testing.

Circuit/System Testing

Note: When removing connectors, inspect for damage or corrosion. Damage or corrosion in the following requires repair or replacement of the

affected component/connector:

* Seat position sensor

* SDM module

* Seat position sensor wiring harness connector

* SDM wiring harness connector

1. Ignition OFF, disconnect the harness connector at the appropriate B88 seat position sensor.

2. Test for less than 10 ohm between the low reference circuit terminal 1 and ground.

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2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 3111

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

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)