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 electronic brake control module (EBCM) sends a central area network (CAN) serial data message to the serial data gateway (SDG) module. The SDG module converts the CAN message to a class 2 serial data message and sends the message to the instrument panel cluster (IPC). The IPC interprets the class 2 message from the SDG module and commands the Antilock Brake System (ABS) indicator ON or OFF.
Diagnostic Aids
| • | If your vehicle is showing the brake or low air warning light is on and you either are not equipped with ABS or do not have an ABS warning light ON then there is a problem with the regular brake system. |
| • | Replace the Instrument Panel Cluster (IPC) if the ABS indicator intermittently fails to operate during the bulb check. |
| • | The malfunction must be present during diagnosis in order to prevent unnecessary parts replacement. Always begin diagnosis with the Diagnostic System Check refer to Diagnostic System Check - Vehicle. |
Reference Information
Schematic Reference
Antilock Brake System Schematics
Connector End View Reference
Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for EBCM and IPC
Circuit/System Verification
Ignition ON, Observe the Instrument Panel Cluster (IPC) Antilock Brake System (ABS) indicator. The ABS Indicator should illuminate.
Circuit/System Testing
Important: Diagnose all vehicle DTCs before using this diagnostic.
With the scan tool, select instrument panel special functions Display Test. Command the instrument panel warning lamps ON.
| ⇒ | If the ABS warning lamp does not turn ON, replace the IPC. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for IPC replacement, setup, and programming
Repair Verification
- Ignition OFF for 5 seconds.
- Ignition ON, observe the ABS Warning Light Indicator.
- The ABS Warning Light Indicator should light for 2 seconds then turn off.
| ⇒ | If the ABS indicator does not light, recheck the circuit/system testing. |
