What Causes the ABS and EPS Lights to Illuminate?
2 Answers
ABS and EPS lights may illuminate due to faults in components such as wheel speed sensors, ABS wiring, ABS pump, pressure modulation solenoid valves, or the ABS control module. How ABS Works: During braking, the ABS system rapidly determines wheel lock-up status based on speed signals from each wheel speed sensor. It then closes the normally open inlet valve for the locking wheel to maintain braking force. If the wheel continues to lock, the normally closed outlet valve opens, allowing brake fluid to return directly to the reservoir through the pipeline, rapidly reducing braking pressure on that wheel to prevent complete lock-up. This keeps braking at the optimal point (20% slip ratio S), achieving maximum braking effectiveness and driving safety. Functions of ABS: 1. Maximizes brake effectiveness, reducing braking time and distance. 2. Effectively prevents vehicle skidding and fishtailing during emergency braking, ensuring good driving stability. 3. Allows steering during emergency braking, maintaining good steering control. 4. Avoids severe friction between tires and road surface, reducing tire wear.
Having driven for over a decade, I know ABS and EPS warning lights coming on together demand serious attention. Last time when the lights lit up on a suburban road, my brake pedal suddenly stiffened and steering felt like pushing a boulder, making my palms sweat as I urgently pulled over. An experienced mechanic told me it could be wheel speed sensors clogged with mud, or a blown fuse affecting the ABS system; EPS light often indicates loose connections in the power steering motor. With ABS failure, hard braking may lock wheels causing skids in rain; without EPS assistance, parking maneuvers become exhausting. Avoid highways and check fuse box yourself—if unsure, visit a professional shop. Regularly clean undercarriage to prevent sensor fouling, addressing issues early prevents major incidents.
