Circuit Description
WARNING: This page is about a different car, the 2004 Pontiac Grand Prix. However, it is still accessible from the selected car via links, so may be relevant.
The TRAC OFF indicator is controlled by the instrument cluster via class 2 serial data messages from the EBCM. When the body control module (BCM) sees the traction control switch input grounded through the momentary traction control switch, it sends a class 2 message to the EBCM that tells the EBCM that the traction control switch has been pressed. The EBCM then disables traction control and sends a message to the instrument cluster to turn the TRAC OFF indicator ON. Each time the ignition is cycled from OFF to ON, the traction control system is enabled.
The following conditions will cause the TRAC OFF indicator to illuminate:
- The EBCM has disabled the TCS due to a DTC.
- The driver manually disabling the TCS via the traction control switch.
- The instrument cluster bulb check. When the ignition switch is turned to ON, the TRAC OFF indicator will turn on for approximately 3 seconds and then turn OFF.