The basic components common to all anti-lock brake systems include wheel sensors, an electronic control unit, an ABS warning light, and a hydraulic modulator assembly with electrically operated solenoid valves. Usually, the control unit and the hydraulic control unit (HCU) are built together; sometimes they can be separated and purchased separately; sometimes they can’t.
If your vehicle has an anti-lock braking system (ABS), it should have a tone ring-on each wheel hub, but don’t be surprised if you can’t see it. Sometimes it’s hidden and you can’t see it unless you remove the wheel speed sensor. Other times it’s plainly visible. It may be part of the CV joint or it may be part of the brake rotor. It can also just be a magnetic array built into the hub bearing seal, which is totally invisible.
In most cases, these circular objects look a lot like bicycle sprockets with teeth. Each ring has awheel speed sensor that monitors how fast each wheel is spinning. The number of sensors may differ depending on how the system is configured.
Before pulling your vehicle apart to check the ABS, use ascan tool first to determine whether or not there’s a system fault. You can also check if the ABS warning light is on. ABS-related issues are often tied to other factors, includinglow or high tire pressure, lowbrake fluid level, and fuse operation.
There are some vehicles that have a switch on the control panel that can disable ABS operation, but this feature can vary from one model to another.
Consider consulting a brake specialist before attempting any fixes on your vehicle, as brake repairs may require advanced technical knowledge.
Any information provided on this Website is for informational purposes only and is not intended to replace consultation with a professional mechanic. The accuracy and timeliness of the information may change from the time of publication.