Anti-Lock Brake System: Operation

ABS control module receives a wheel speed signal from each wheel sensor. When wheel lock-up is about to occur, the ABS control module activates 4 solenoid valves to modulate hydraulic pressure to each wheel. A pump/motor provides constant hydraulic pressure to the system. The ABS incorporates self-diagnostic capabilities and can store Diagnostic Trouble Codes (DTCs) in the ABS control module.

Two warning lights (Yellow ABS and Red BRAKE) alert driver of problems in braking system. Red BRAKE warning light monitors master cylinder fluid level and parking brake lever status. Yellow ABS warning light alerts driver of problems in ABS/TCS.

Traction control systems controls wheel spin by modulating engine torque through PCM, and applying and releasing appropriate brake when one or more wheels lose traction and begin to slip. System can be disabled by depressing traction control switch. Switch also contains an LED indicator which lights when traction control is engaged.