Diagnostic Notes

RABS Valve Mini Schematic:

DESCRIPTION
Code 4 is generated when the antilock electronic control module detects a short circuit (less than 10k ohms) in Circuit 535 (LB/R). This can indicate an open or short in the reset switch circuit, or a hydraulic leak into dump section of the RABS valve.

POSSIBLE CONTRIBUTING BASE BRAKE COMPONENT/VEHICLE WIRING CONCERNS
- Terminal backout in the antilock electronic control module harness connector at Pin 6.
- Terminal backout in the RABS valve harness connector at Pins 2 or 3.
- Bulkhead connector (between engine compartment and instrument panel) terminal backout or loose connection.
- Antilock electronic control module or RABS valve connectors not fully matted with component.
- Intermittent open or open circuit in Circuits 535 (LB/R), or 274 (BK/W).
- Intermittent short or short circuit in Circuit 535 (LB/R).
- Defective RABS valve.
- Worn or damaged antilock electronic control module.