2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 993

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 993

1. Ignition OFF, disconnect the harness connector at the EBCM.

2. Test for less than 1 ohm between the ground circuits listed below and ground.

* Terminal 13

* Terminal 38

瀚慖f greater than the specified range, test the ground circuit for an open/high resistance.

3. Ignition ON, verify that a test lamp illuminates between the B+ circuits listed below and ground.

* Terminal 1

* Terminal 25

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

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

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 EBCM replacement, setup, and programming

C123D

DTC C056D, C120C, C121C, C121E, C121F, C123A-C1256, C126E-C127C, C12C2-C12DB, C12DE, C12DF, or C12F2-C12F6

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 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