What are the reasons for the ABS warning light to illuminate?

[EvelynMarie]

ABS warning light may illuminate due to signal attenuation or loose wiring, requiring sensor cleaning and wiring reinstallation. When the sensing part of the ABS speed sensor is covered by mud, sludge, or other contaminants, it affects the sensor's ability to detect the corresponding speed signal. This prevents the ABS control unit from identifying the vehicle speed and determining the wheel slip rate, thus failing to issue appropriate commands to adjust braking. Solution: Clean the dirt from the speed sensor and adjust the gap between the speed sensor and the signal ring to restore normal function. System malfunctions can also occur due to poor signal quality caused by loose connections between system wiring or poor contact in ABS relays. The most common issue is a loose connection in the speed sensor wiring harness, which will also show as a poor speed sensor signal in the ABS control unit's fault memory. Solution: Inspect wiring connections and reconnect any loose parts.