The ABS light is always on - generally divided into the following three situations:
1. Turn on the ignition switch, the ABS fault light is always on.
Under normal circumstances, the following three situations will cause this failure of the ABS system:
1. When the vehicle speed exceeds 10km/h, no speed signal is transmitted to the ABS control unit.
2. When the vehicle speed is greater than 40km/h, the speed signal exceeds the tolerance value.
3. The sensor has an identifiable open circuit or a short circuit fault to positive and ground.
If you encounter the above situation, you should focus on the following items:
1. The connection between the wheel speed sensor and the ABS control unit.
2. The installation clearance and installation position of the wheel speed sensor and the ring gear, and the condition of being polluted by dust or impurities.
3. Whether the wheel bearing clearance is too large.
4. The sensor itself is faulty.
Tips: When cleaning the vehicle, often use high-pressure water to flush the engine compartment, the high-pressure water will splash into the connection point of the ABS control unit, and it will cause an instant short circuit after corrosion. This is a soft fault, and the probability of the fault is very random. Generally, it is not easy to measure with a multimeter, and only when the fault occurs can the cause of the fault be found, the root cause of the problem can be found, the right medicine can be prescribed, and the fault can be eliminated.
