Circuit Description

The instrument panel cluster (IPC) illuminates the Stabilitrak indicator during the IPC bulb check or when the electronic brake control module (EBCM) sends a serial data message to the IPC commanding the indicator ON. The 5 inputs to the electronic brake control module (EBCM), which are used solely for vehicle stability enhancement, are the longitudinal accelerometer, lateral accelerometer, yaw rate sensor, master cylinder pressure sensor, and the steering wheel position sensor. The EBCM must detect valid inputs from all 5 sources during the initialization period in order to enable the vehicle stability enhancement system (VSES). Initialization must occur during the first 3 000 meters of vehicle travel or 1 000 meters of straight vehicle travel. If initialization cannot be achieved during this time period, the VSES remains inactive and the stability system not ready indicator is illuminated. The EBCM does not attempt to reinitialize until the next ignition cycle. One or more DTCs often set, shortly after an unsuccessful initialization attempt, indicating the root cause of the failure. If this occurs, the stability system not ready indicator is no longer illuminated.