Is it normal for the ABS light to come on and then go off after restarting?
2 Answers
ABS light comes on and then goes off after restarting. If the ABS warning light is on, it is recommended not to continue driving. Because the ABS light indicates a malfunction in the vehicle's anti-lock braking system, during emergency braking, if the wheels lock up, the vehicle may lose control and skid, making it difficult for the driver to slow down or adjust the vehicle's trajectory, posing significant safety risks. The role of ABS: To maximize the effectiveness of the brakes, reducing braking time and distance. It effectively prevents vehicle skidding and fishtailing during emergency braking, ensuring good driving stability. It allows steering during emergency braking, providing excellent steering control. It avoids severe friction between the tires and the ground, reducing tire wear. How ABS works: During braking, ABS quickly determines the wheel lock-up status based on the speed signals from each wheel speed sensor, closing the normally open input solenoid valve on the wheel that is starting to lock, keeping the braking force constant. If the wheel continues to lock, the normally closed output solenoid valve is opened, causing the braking pressure on that wheel to drop rapidly due to the direct connection to the brake fluid reservoir, preventing the wheel from fully locking due to excessive braking force. This keeps the braking state at the optimal point (slip rate S of 20%), achieving the best braking effect and the highest driving safety.
I often encounter the situation where the ABS light comes on and then returns to normal after restarting the engine, which feels quite common. This is usually caused by some intermittent minor faults, such as the wheel speed sensor getting contaminated with dirt or rain interference, or a slightly loose circuit connection. Restarting the engine can clear temporary errors, but it doesn't mean the problem has been resolved. The ABS system is crucial as it prevents wheel lock-up during emergency braking, enhancing safety. I once experienced the light coming on but didn't pay much attention, and later nearly had an accident in rainy and snowy weather. So, I recommend that even if it returns to normal, you should take the time to visit a professional repair shop for a comprehensive check, especially to see if there are any issues with the sensors and brake wiring. Regularly cleaning the wheel speed sensors and checking the fuses are simple yet effective measures—don't ignore them to avoid bigger troubles.
