ABS Indicator Always On
ABS Indicator Always On
Circuit Description
The instrument cluster controls the operation of the Antilock Brake System (ABS) indicator. The electronic brake control module (EBCM) reports the desired status of the ABS indicator via serial data messages. The ABS indicator signal circuit is a back-up reporting circuit to the serial data messages. The EBCM supplies ground through the circuit when the ABS is operating properly. When there is a problem with ABS that should turn on the ABS indicator, the EBCM opens the ABS indicator signal circuit. If there is a problem with the ABS serial data messages, the instrument cluster uses the ABS indicator signal to determine if the ABS indicator should be illuminated. Using the serial data messages and back-up circuit, the instrument cluster decides whether to turn on the ABS indicator.
Test Description
The numbers below refer to the step numbers on the diagnostic table.
3. Use the scan tool to check the normal state of the ABS indicator control circuit.
4. Ensures that the instrument panel cluster (IPC) can operate the ABS indicator.
