2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 3139

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 3139

6. If equipped, verify that a test lamp illuminates between each B+ circuit terminal 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. If the circuit fuse is open, test the

control circuits of the control module for a short to ground. If the circuits test normal, replace the control module.

7. If equipped, ignition ON, verify that a test lamp illuminates between each ignition circuit terminal and ground.

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

the control circuits of the control module for a short to ground. If the circuits test normal, replace the control module.

Note: Only the high speed GMLAN modules have a serial data communication enable circuit OR an accessory wakeup serial data circuit,

and the BCM is the output for these circuits. Refer to the module schematics to identify which modules have these circuits.

8. If equipped, ignition ON, verify that a test lamp illuminates between the communication enable circuit terminal OR the accessory wakeup

circuit terminal and ground.

瀚慖f the test lamp does not illuminate, test the circuit for an open/high resistance. If the circuits test normal, replace the BCM.

9. Ignition OFF for 60 seconds, test for less than 5 ohm between the serial data circuit terminals and the appropriate DLC terminal listed below:

* Class 2 serial data circuit terminal 2

* Low speed GMLAN serial data terminal 1

* High speed GMLAN serial data terminal 6 or 14

瀚慖f greater than the specified range, test the serial data circuit for an open/high resistance between the non communicating control module

and a control module setting the DTC or a serial data splice pack.

10. If all circuits test normal, replace the control module that is not communicating.

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)

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

programming

C126C, C126D, C12E3, or U180F

DTC C126C, C126D, C12E3, or U180F

Diagnostic Instructions

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