Normal Operation

The traction control system operates using the ABS module to interact with the PCM to reduce engine torque if one or more of the drive wheels lose traction and begin to spin during acceleration. Engine torque modulation is achieved by regulating fuel and spark to the cylinders.

The stability control utilizes several sensor inputs (wheel speed, steering wheel rotation, stability sensors, brake pedal) to monitor the vehicle motion relative to the intended course. If the system determines that a vehicle instability event is about to occur, it takes action to adjust brake torque at specific wheels and to reduce engine torque to reduce the cornering forces and, therefore, the total roll moment acting on the vehicle.

If a MyKey®-restricted key is in use that has the AdvanceTrac® always-on feature configured "on", the stability/traction control system cannot be disabled.

The stability/traction control switch is a momentary contact switch and is part of the liftgate release and hazard switch assembly. When the switch is disabled, the ABS module is momentarily grounded through the switch. The ABS module then sends a message to the PCM along the High Speed Controller Area Network (HS-CAN) to disable the traction control function. The ABS module also sends a message over the HS-CAN  to the Instrument Cluster (IC) to illuminate the stability/traction control indicator (sliding-car icon).

This pinpoint test is intended to diagnose the following: 

• Wiring, terminals or connectors
• Stability/traction control switch
• ABS module