Anti-Lock Brake System: Operation

In anti-lock braking mode (wheel speed signals indicate a wheel is about to lock-up), ABS ECM operates 4 independent control solenoids to increase or decrease pressure as necessary to prevent wheel lock-up. This function continues as long as necessary during braking.

The ABS system also has self-diagnostic system which utilizes a "failure" mode. When system detects a malfunction, ABS ECM disables anti-lock braking and allows normal braking only. System then stores a Diagnostic Trouble Code (DTC) and illuminates ABS warning light (ABS service reminder indicator). Trouble codes are retrieved for diagnosis through use of ABS warning light. See DIAGNOSIS & TESTING .