2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 687

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 687

DTC Descriptor

DTC B2725 08

- Active Transfer Case Mode Switch Circuit - Signal Invalid

Diagnostic Fault Information

Circuit/System Description

The transfer case shift control switch (TCSCS) has 3 modes. The transfer case shift control module (TCCM) supplies a regulated 5 V DC 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.

The NP0 transfer case has the following 3 modes:

* 2 Hi

* 4WD Auto

* 4 Hi

Conditions for Running the DTC

* Ignition ON.

* System voltage 10.5-18 V.

Conditions for Setting the DTC

* The system constantly monitors the voltage on switch signal circuit.

* If the system detects a voltage level under 0.38 volts or greater than 4.86 volts for 60 seconds, the DTC is logged.

Action Taken When the DTC Sets

* All shifting is disabled.

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

* Failure Records will be stored.

Conditions for Clearing the DTC

* The TCCM will clear the current DTC once the conditions for setting the DTC are no longer present.

* 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

EL-49742 - harness is a good source for B+ and ground.

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)

* 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