How To Troubleshoot ABS System In A Car? Effective Ways

An anti-lock brake system (ABS) is integral to your car’s safety. Without it, your car will have difficulty regaining and maintaining traction on slippery surfaces like wet roads or icy patches. To ensure your brakes work correctly each time you use them, it’s important to know how to repair an ABS brake system if it fails and trips the warning light.

When the ABS warning light turns on, the problem could be minor, like a malfunctioning wheel speed sensor or something more complex such as a fault in the electronic control unit (ECU). Either way, it should be addressed immediately as it could affect the performance of your braking system.

If you can address the problem yourself accurately with our guide, you’ll save yourself a considerable amount of money in repairs. However, if you’re not confident about doing it yourself, then by all means, having a certified mechanic take a look at your vehicle should always be given precedence.

How to Troubleshoot ABS System in A Car?

ABS, or Anti-lock Brake System, is an important safety feature on cars that helps stop the wheels from locking up during sudden braking. If your car’s ABS system malfunctions or stops working, it can be very dangerous.

Therefore, knowing how to troubleshoot your car’s ABS is important to keep yourself and others safe. Follow the below steps to troubleshoot the ABS in a car:


One of the most common methods for troubleshooting ABS brakes is to turn the key in the ignition and turn the car on and off for a few seconds. This procedure usually activates a warning light if there is an ABS-related problem.

If the ABS light appears on the dashboard, turning it off and back on should reset any code stored in memory, causing the problem. However, if, after doing this procedure multiple times, the problem persists, then it might be time to bring your vehicle to a mechanic shop.

More thorough troubleshooting can occur at a mechanic shop since they can access special tools such as diagnostic scanners. By connecting these scanners with your vehicle’s ABS controller, they can obtain information about the exact issue causing the issue, which makes diagnosing errors much faster and easier.

With this accurate diagnosis, they will be better equipped to fix any issues that may be present relating to their braking system quickly and efficiently without any further damage or complications.


Cleaning the front wheel sensors is important in ensuring your ABS system’s performance. If, at low speeds, your ABS pulses while the brake pressure is being applied, it could be a sign that something isn’t quite right. It can be due to dirt or debris clogging up the wheel speed sensors, part of the ABS system.

When this occurs, it’s best to take your vehicle to a certified mechanic shop with experience with ABS systems. They can inspect and ensure they correctly clean any unwanted buildup on the wheel speed sensors.

This should restore your Anti-lock Braking System’s functionality to normal so you can rest easy while driving in all road conditions. It’s important that before contacting a mechanic shop, you make sure the debris build-up isn’t caused by some other issue with your car, such as worn bearings or lack of lubrication.


In the third step of working on a brake issue in your car, pressure must be applied to the ABS brake if it won’t stop. This safety precaution should be done carefully and gently with steady, even pressure. On top of that, one must check to see if the master cylinder brake fluid is low and needs to be filled back up again.

To do this, open the master cylinder lid, remove the old fluid, and fill it to approximately two-thirds of the marked level on its side or top before closing it.

Another measure one may take when faced with an unresponsive ABS brake is looking for air bubbles in the hydraulic system. If so, you need to bleed out all air bubbles from the system using tools like special vacuum pumps or bleeding kits, which can help locate any air pockets more easily.

In some cases, this might involve removing certain parts, such as hoses, and pumping them manually until new blackened oil appears at their end where no more visible air bubbles remain present. By taking these steps carefully yet quickly and correctly, you should find a resolution to your unresponsive brakes shortly afterward.


Step 4 in resolving a clunking sound when pressing ABS brakes is to replace any loose or broken front-end parts. If this is not the source of the problem, then the best solution is to bring your vehicle to a repair shop for servicing. It’s important to use reputable professionals experienced in repairing ABS brakes, as they can pinpoint exactly what needs to be fixed. 

They can also provide valuable advice on maintaining and servicing your ABS brakes so that you don’t need to face any such issues in the future. Regularly scheduled service appointments can help ensure that everything stays in top condition while also preventing avoidable damage from occurring due to negligence.

Be sure to heed the warnings from a qualified technician if any concerning signs may lead to costly repairs down the line.


Check the ABS brakes for any signs of damage. Signs of damage can include broken wires, bent or cracked pins, and other defects in the brake system. If this is not the source of the problem, then it may be time to check out the wheel speed sensors.

These are located at each wheel and send information about wheel speed to the ABS controller so it can modulate the brakes accordingly.

Check to make sure that they are properly connected and functioning correctly. If there is still a problem, the ABS control unit may need to be checked for faults or defects. This can require more complex diagnostics, such as using software to view the data sent by the wheel speed sensors, which a qualified technician should do.


The next step to troubleshooting the ABS in a car is to examine the wheel speed sensors for any signs of debris or buildup. This can cause false readings, which will affect the operation of your Anti-lock Braking System. Cleaning these parts should be done cautiously, as you don’t want to damage them while removing unwanted substances.

If this is not the source of the problem, then it may be time to check the ABS controller for faults. This requires more complex diagnostics, such as using software to view the data sent by the wheel speed sensors, and should only be done by a qualified technician.

Frequently Asked Questions [FAQs]

1. Can A Faulty ABS Be Repaired?

Yes, a faulty ABS can be repaired. To troubleshoot and repair the problem, you must first diagnose the issue using an OBD-II scanner. This will help you determine what code is causing the ABS system to malfunction. Once the code has been determined, you can research online for possible solutions or contact a qualified mechanic for assistance.

2. How Much Does It Cost To Fix An ABS?

The cost of repairing an ABS system will vary depending on the vehicle’s make and model and the repair’s complexity. On average, a complete ABS system replacement can cost anywhere from $300 to $800. However, smaller repairs may only cost around $150-$250. Be sure to get a quote from a qualified mechanic before starting work on your car’s ABS.

3. What Sensor Controls ABS?

An Anti-lock Braking System (ABS) is used in cars that controls the brakes so they do not lock up when braking suddenly or on slippery surfaces. The main components of the ABS are the control module, wheel speed sensors, and hydraulic valves.

4. Can You Clean ABS Sensors?

The ABS sensors in a car can often become clogged with dirt, dust and debris, making them less effective or even causing them to malfunction. To clean the sensors, you should start by disconnecting the battery and removing the wheel and tire assembly from the vehicle. Then, use compressed air to blow out any debris stuck in or around the sensor.

5. How Many Sensors Are In An ABS System?

An ABS generally contains several components, including wheel sensors, an electronic control module, and a hydraulic control unit. In typical situations, the system distributes hydraulic pressure to all four brakes while applying pulsing pressure to prevent skidding.


Troubleshooting an ABS system in a car requires careful diagnosis and attention to detail. By checking for signs of damage, ensuring wheel speed sensors are connected properly, and examining the ABS controller for faults, you can identify the source of the problem. Additionally, cleaning or replacing wheel speed sensors can help improve the performance of your Anti-lock Braking System.

John D. Archer

John D. Archer is a mechanical engineer and writer based on the area of automotive accessories at, A resident expert and professional, John is passionate about all things automotive and loves to share his knowledge. He has good experience in all kind of automotive accessories. He has worked as a chief mechanical engineer in some reputed automotive garage firm.