2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 689

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 689

TCCM - Mode Switch Circuit

1. Key ON, engine OFF. Install the TCSCS.

2. Using the Data Display feature of the scan tool, monitor the Mode Switch Supply and Return Voltages while turning the TCSCS through

each mode.

瀚慖f the voltage is less than the specified value, test the affected circuit for an open/high resistance, short to ground or short together. If all

circuits and connections test normal, reprogram the TCCM. If the DTC resets replace the TCCM.

瀚慖f the voltage is greater than the specified value, test the affected circuit for a short to voltage. If all circuits and connections test normal,

reprogram the TCCM. If the DTC resets replace the TCCM.

3. Perform the Circuit/System Testing.

Repair Instructions

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

* Transfer Case Shift Control Switch Replacement (Without SLT) (See: Powertrain Management/Transmission Control Systems/Sensors and

Switches - Transmission and Drivetrain/Sensors and Switches - Transfer Case/Four Wheel Drive Selector Switch/Service and Repair)

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

* Transfer Case High/Low Clutch Reset (See: Transmission and Drivetrain/Transfer Case/Testing and Inspection/Symptom Related

Diagnostic Procedures/MP 3023/3024-NQH - Transfer Case/Transfer Case High/Low Clutch Reset)

MP 3023/3024-NQH - Transfer Case

DTC B2725

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 B2725 08

- Active Transfer Case (ATC) Mode Switch Signal Invalid

Diagnostic Fault Information

Circuit/System Description

The active transfer case mode switch circuit consists of 5 modes. The transfer case shift control module (TCCM) supplies a regulated 5 volts to the

switch through the 5-volt reference circuit. The current travels through the specific resistor of the currently selected mode - each mode has its own

resistor. The current is then returned to the TCCM through the switch signal circuit.

The TCCM continuously monitors the switch signal circuit to determine whether a mode change has been requested by the driver.