Traction Control System

The traction control system uses the ABS and the PCM to limit wheel spin. When the ABS module detects a wheel spinning excessively, brake pressure to the appropriate brake caliper is modulated. This is accomplished by opening and closing the appropriate solenoid valves inside the HCU  while the hydraulic pump motor is activated. At the same time, the ABS module sends a message over the HS-CAN  that a traction control event is taking place. When the IPC  receives this message, it flashes the stability control light. If the event is severe enough, the ABS module sends a message to the PCM over the HS-CAN  to assist with traction control. When the PCM receives this message, it adjusts engine timing and decreases fuel injector pulses. Once the affected wheel returns to normal speed, the ABS module returns the solenoid valves in the HCU  to their normal position, deactivates the hydraulic pump motor and sends another message over the HS-CAN  indicating the traction event has ended. The PCM returns engine timing and fuel injectors to normal operation and the IPC  turns off the stability/traction control indicator (sliding-car icon) light.

Once vehicle speed reaches or exceeds 100 km/h (62 mph), traction control is accomplished only through PCM intervention.

Certain DTCs in the ABS module disable the traction control system. Depending on the DTCs present, the yellow ABS warning indicator and/or the stability/traction control indicator (sliding-car icon) light is illuminated.