ABS Indicator Inoperative

ABS Indicator Inoperative





Circuit Description
The electronic brake control module (EBCM) turns ON the antilock brake system (ABS) indicator by grounding the ABS indicator control circuit. When the ignition switch is turned to the ON position, the EBCM turns ON the ABS indicator for 3 seconds for a bulb check. If the EBCM detects a malfunction, the ABS indicator will stay ON to warn the driver that the ABS is disabled and needs service.

Diagnostic Aids
Thoroughly inspect the wiring and the connectors. An incomplete inspection of the wiring and the connectors may result in a misdiagnosis, causing a part replacement with the reappearance of the malfunction.
The following are possible causes of the malfunction:
^ An open or high resistance in the ABS indicator control circuit
^ An open, high resistance or short to ground in the instrument panel cluster (IPC) ignition voltage circuit
^ An open or high resistance in the EBCM ground circuits
^ An internal EBCM malfunction
^ An internal IPC malfunction

If an intermittent malfunction exists, refer to Testing for Intermittent Conditions and Poor Connections.

Test Description
The numbers below refer to the step numbers on the diagnostic table.
4. This step tests the EBCM ABS off warning lamp circuit for an open or high resistance.
5. This step tests the IPC ignition voltage circuit for an open, high resistance or short to ground.
6. This step tests the EBCM ground circuits.