2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 935

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 935

DTC C0397

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.

DTC Descriptor

DTC C0397 64

- Transfer Case Clutch Performance Actuator Slipping

Diagnostic Fault Information

Circuit/System Description

In 4WD Auto mode, the transfer case shift control module (TCCM) monitors the front and rear wheel speed sensors for slip. If the TCCM detects

slip, and is unable to correct for a difference between the front and rear speed sensors, it will command the transfer case to apply the clutch. In

addition, the TCCM tests for clutch pack wear by performing a high side kiss point check at power down and comparing it to the incremental

position sensor reading.

Conditions for Running the DTC

* Ignition ON.

* System voltage 10.5-8 V.

Conditions for Setting the DTC

The transfer case is unable to correct for slip.

Action Taken When the DTC Sets

* Shifting is still possible but in a reduced capacity which may cause undesirable slip correction events.

* The SERVICE 4WD indicator remains illuminated for the remainder of the current ignition cycle.

Conditions for Clearing the DTC

* The TCCM clears the DTC once the condition for setting the DTC no longer exists.

* A history DTC clears after 40 consecutive warm up cycles without a fault present.

* History DTCs can be cleared using a scan tool.

Diagnostic Aids

Faulty wheel speed sensors can cause this DTC to set. When driving at a steady speed, the scan tool should display the same values for the

following data parameters in the electronic brake control module (EBCM):

* Left and right front wheel speed sensors

* Left and right rear wheel speed sensors

Reference Information

Schematic Reference

Transfer Case Control Schematics (See: Transmission and Drivetrain/Transfer Case/Diagrams/Electrical Diagrams/MP 3023/3024-NQH -

Transfer Case)

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)