ABS Indicator Malfunction

ABS Indicator Malfunction

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions provides an overview of each diagnostic category.



Circuit/System Description

The instrument panel cluster (IPC) illuminates the Antilock Brake System (ABS) indicator by supplying ground to the lamp. The electronic brake control module (EBCM) sends a serial data messages to the IPC, in order to command the indicator ON or OFF.


Reference Information
Schematic Reference

Antilock Brake System Schematics ([1][2]Antilock Brakes / Traction Control Systems)
Connector End View Reference

Component Connector End Views
Description and Operation

ABS Description and Operation (W JL4) (ABS Description and Operation (With RPO JL4))ABS Description and Operation (W/O JL4) (ABS Description and Operation (Without RPO JL4))
Electrical Information Reference

* Circuit Testing
* Connector Repairs
* Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs

Scan Tool Reference

Control Module References for Scan Tool Information


Circuit Verification

Ignition ON, observe the ABS indicator to turn ON then OFF during the IPC bulb test.


Circuit/System Testing

Ignition On, with a scan tool command the Scan Tool IPC display test ON and OFF. The ABS indicator should turn ON and OFF.

If the ABS warning lamp does not turn ON and OFF, replace the IPC.



Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.


Control Module References for EBCM or IPC replacement, setup, and programming