2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 3280

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 3280

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

Diagnostic Aids

A false DTC U1812 can set if the engine does not crank while the ignition key is held in the start position for greater than 3 seconds. Diagnose the

engine does not crank condition first.

Reference Information

Schematic Reference

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

Diagrams)

* Hybrid Controls Schematics (See: Hybrid Drive Systems/Diagrams/Electrical Diagrams)

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)

Circuit/System Verification

1. Verify that DTC U1862 is not set in the HPCM.

瀚慖f the DTC is set, refer to DTC U1862 (See: U Code Charts/U1862).

2. Verify that DTC B137A is not set in the SDG module.

瀚慖f the DTC is set, refer to DTC B137A (See: B Code Charts/B137A).

Circuit/System Testing

1. Ignition OFF, disconnect the inline harness connector X350 at the drive motor generator battery.

2. Ignition ON, verify that a test lamp illuminates between the wake up signal circuit terminal 10 X350 and ground.

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

瀚慖f the test lamp illuminates, test the wake up signal circuit of the drive motor generator battery control module electrical harness for an

open/high resistance.

3. If all circuits test normal, replace the drive motor generator battery control module.

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

U1813

DTC U1813

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.