Is It Safe to Continue Driving When the ABS Light Comes On?

[MacJack]

When the ABS warning light is illuminated, it is recommended not to continue driving. 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 decelerate or adjust the vehicle's trajectory, posing significant safety risks. The ABS light can illuminate in various states, each with different causes and solutions, as detailed below: State 1: ABS warning light remains constantly on (most common). Cause 1: The ABS wheel speed sensor's sensing area is covered by dirt, mud, or other contaminants, affecting the sensor's ability to detect the corresponding speed signal. This prevents the ABS control unit from determining the vehicle speed and wheel slip rate, thus failing to issue appropriate commands to regulate braking. Solution: Clean the dirt from the wheel speed sensor and adjust the gap between the sensor and the signal ring to restore normal function. Cause 2: Poor signal transmission due to loose system wiring connections or faulty ABS relay contacts. Solution: Inspect wiring connections and reconnect any loose parts. State 2: ABS warning light intermittently illuminates but turns off during acceleration. Cause: When multiple vehicle electrical components are in use, the battery voltage drops below 10.5V. As engine speed increases and voltage rises, the ABS light turns off. This may also occur if the ABS system's power supply voltage is too low, such as due to poor terminal contact or grounding issues. Solution: Check the battery's specific gravity, inspect the charging system, and examine the power supply (e.g., voltage relay or poor power contact). State 3: ABS warning light remains on after engine start and only turns off when the engine is turned off (IGFF). Cause: Poor grounding of the ABS hydraulic valve body; loose wiring connections at the ABS hydraulic valve body; or ABS control unit malfunction. Solution: Loosen and retighten the hydraulic valve body's grounding screw, cleaning the contact surface if necessary. Check for enlarged terminal gaps and replace the ABS or ABS/ASR control unit if needed. State 4: ABS warning light illuminates during high-speed driving. Cause: The ABS control unit detects a significant discrepancy between rear and front wheel speed signals during high-speed driving. This may also occur due to incorrect tire or wheel rim specifications. Solution: Refer to the vehicle's specified tire and wheel rim sizes, as indicated on the fuel tank cap label. State 5: ABS warning light intermittently illuminates. Cause: Improper adjustment of the brake light switch; poor internal contact in the brake light. Solution: With the engine running, press the brake pedal and manually push the brake switch linkage down fully, then release the pedal to complete self-adjustment. Replace the brake light switch if necessary.