[Maintenance failure] WABCO abs failure categories and technical solutions

It is inevitable that some faults will occur after the equipment has been used for a long time. After investigation, it is found that there are three main types of faults, circuit faults, mechanical faults and external interference. Let's take a closer look at it.

1. Circuit failure

When the power is turned on, the ABS indicator light should be on, and once the vehicle speed reaches 10km/h, the indicator light should automatically go out, otherwise it means that the ABS is faulty.

ABS pressure regulators all use solenoid valves, and if the voltage is too high, it may burn out, and if the voltage is too low, it may not work properly.

Generally, the power supply voltage should not exceed ±15% of the rated voltage of the solenoid valve, and the same problem as above exists for the electronic control unit, otherwise the ABS will malfunction.

2. Mechanical failure

The pulse ring is an iron gear ring, which plays the role of changing the magnetic field of the sensor. It is fixed to the hub and does not come into contact with any components. Some people do not understand this, and mistakenly think that the pulse acts as a gear transmission, and add lubricating oil or lubricant to it, so that iron filings and other debris accumulate on it, and the accumulation of impurities will inevitably destroy the sensitivity of the sensor.

The pulse ring is not coaxial with the hub, and the gap between the sensor and the pulse ring varies, which will affect the test accuracy of its wheel motion. The reasons for this situation are generally improper installation of the pulse ring, deformation of the pulse ring (unnecessary impact on the pulse ring when the vehicle is repaired), wheel bearing wear and looseness, etc. Damage to the pulse ring will also affect the accuracy of testing the parameters of the four-wheel motion state.

In the case of the above situation, when the pulse ring needs to be replaced, the problem of the sensor and the pulse ring should be re-determined (0.2~0.5mm).

3. External interference

The pressure regulator, the ABS circuit is good, and the sensor can accurately measure the wheel movement state.

Poor ABS performance, such as increased braking distance, uncontrolled anti-lock twitch action, etc., is caused by the failure of the pressure regulator.

The minor fault of the pressure regulator is that the response is slow and the gain is improper, and the serious fault is that the work is not controlled by the ABS, and the usual braking function cannot be restored by disengaging the ABS.

The above is the WABCO abs fault categories and processing methods, I hope to help you, in addition to regular maintenance of the anti-lock braking system during use, so as to reduce its failure rate.