Diagnosis & Repair
- ABS control unit has detected a malfunction in hydraulic control unit inlet or outlet valves. Raise and support vehicle. Shift transaxle into Neutral. Release parking brake. Ensure no hydraulic system leaks exist. If hydraulic system leaks are found, repair as necessary. If no hydraulic system leaks are found, rotate each wheel by hand to ensure smooth rotation. If all wheels rotate, verify each wheel does not rotate with brake pedal depressed.
- If each wheel does not rotate with brake pedal depressed, hydraulic system is functioning properly. Replace hydraulic control unit. If any wheel does not rotate, check hydraulic system for binding caliper, blocked brake line or parking brake malfunction. Repair as necessary. If components are okay, replace hydraulic control unit.