ABS repair & replacement made easy

What does the ABS system do?

The ABS, or anti-lock braking system, on your car is a super important system that prevents your wheels from locking up and therefore simply skidding across the road surface. The system is especially important when braking in adverse weather conditions, i.e. when the road surface is slippery due to leaves, frost or when there are traces of oil on the road. Because of this, keeping your anti-lock braking systems properly maintained is vital.

There's a couple of components in the system that can cause problems. In many cases it will be the ABS sensors that fail, which means the system will not receive the information it requires to activate the system.

How does an ABS system work and what are the components?

When a brake locks a wheel, it simply slides across the surface, rather than slowing the vehicle in a controlled manner. The most efficient way to resolve this when it occurs is called cadence braking, where the brakes are releases then reapplied in quick succession until the wheels are no longer locked on and sliding. This method came from motor racing and was used by top drivers to control their vehicles. Obviously not everyone has the skills or reactions of a motorsport legend, so systems were developed to do it automatically.

The components are, briefly, the wheel speed sensors and the control module (ECU). The wheel sensors are sending back the road speed of the wheels to the ECU so it can determine if the wheels are rotating or not. The ECU then triggers the braking to “pulse” the brakes on and off until the wheels are no longer locked. This happens very quickly and when it occurs you can feel the pulse in the brake pedal and sometimes hear it too.

How do you know there is something wrong with the ABS?

• The car's ABS warning light stays on permanently once the engine is started.
• The brakes lock up very easily when braking on slippery surfaces.
• The brakes do not respond as well as normal under hard braking

When should you consider replacing the ABS Control Module?

It is rare that an ABS control module has to be replaced as it is an electric component that normally would not need servicing. In some cases, though, it can be that the module's electrical connectors have corroded or that the electrical wires might have been damaged.

Often its ancillaries are more likely to go faulty, like the ABS sensors which can malfunction when covered in debris or grease. Of course, if the ABS warning light is on, it is important to have your car inspected as soon as possible to prevent non-working brakes.

When should you consider replacing the ABS sensors?

You will only know for sure if, and indeed which, ABS sensor requires replacement after a diagnostic investigation has taken place. Therefore we advise in all circumstances that this is carried out prior to booking the replacement of any components.

How common are ABS faults?

At least one of the ABS sensors is likely to fail at some point during a vehicles lifetime so its a common repair for mechanics to carry out across all manufacturers. ABS modules, as explained, do not fail that frequently thankfully but faults can occur of course.

How can I extend the lifetime of the ABS system?

Quite simply there is not a lot you can do to prevent issues from occurring with the system. Damage can occur to the sensors from road debris, water ingress and the day to day vibration of the vehicle in use. Obviously though, driving through deep flood water will hasten any water ingress to all the vehicles components, so common sense should prevail.

What happens during an ABS fault repair?

• Depending on the specific job - an ABS repair may include all or some of the following steps
• Mechanic will diagnostically inspect the ABS system.
• If necessary, the mechanic will replace the faulty ABS sensor and re-test the component.
• If the ABS module is at fault, the mechanic will advise on the best course of action in order to have it repaired.
• Mechanic will test drive and inspect the braking system.

How much does an ABS repair cost?

The cost of an ABS repair depends on your car and what parts your car's manufacturer recommends using for the replacement. Find out what you could save by having your ABS system repaired by Clickmechanic. We can help you with an ABS sensor replacement or ABS ring replacement, just select your car at the top of this page to get a quote.