Pre-Diagnosis Trouble Shooting
- Turn ignition switch from OFF to ON position. Check ABS warning light operation. Ensure ABS warning light illuminates for 2 seconds and then turns off (observe for at least 20 seconds). If ABS warning light illuminates for 2 seconds and goes out, no codes are stored.
- If ABS warning light flashes, check following.
- Intermittent Power To ABS Control Unit
- Grounded Check Connector Lead
- Faulty Control Unit
- Intermittent Control Unit Ground
- If ABS warning light remains on without flashing, at least one code has been stored. Retrieve code from memory, then diagnose and repair fault. Refer to RETRIEVING CODES under DIAGNOSIS & TESTING. If malfunction code can not be retrieved, check following.
- Grounded Check Connector Lead
- Control Unit Power Supply
- Faulty Control Unit
- ABS Fuse
If no problems are found with above components, check pressure differential switch wiring for an open or short. Pressure differential switch is located in proportioning valve.
- If ABS warning light does not illuminate at all, check following.
- Control Unit Harness Connector
- Control Unit Ground
- ABS Warning Light Power
- ABS Warning Light Fuse
- ABS Warning Light Bulb And Wiring