The owner had concerns when she saw the ABS light appear on her 2011 BMW 318D. Worried that she may not be able to continue her journey, she called me up and asked if the car was still safe to drive.

Many motorists do not fully understand that the ABS light being on, is indicating that the antilock braking system is not operating. In the event of emergency braking action, the wheels may lock up, but the brakes will still work. As long as the driver knows that extra caution needs to be taken, then the vehicle is safe to drive to complete a journey.

We all know the wide range of faults that can be the cause of ABS failure. Common issues are a failed sensor, or a corroded reluctor ring. On this BMW, the fault was a combination of both problems. The reluctor ring had corroded and expanded. Then the expanded metal ring had worn through the wheel speed sensor.

A new reluctor ring and sensor was needed, and the driveshaft needed to be removed to carry this job out. Once removed, the driveshaft could then be cleaned up to accommodate the new reluctor ring.

Once all back together, and the system cleared of the fault codes, the BMW was given a quick drive to ensure that all was now well, and that the ABS was operating correctly again.

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