ABS light on: Why? How to turn it off?

When you start having an issue with your vehicle’s anti-lock braking system, the ABS light will turn on immediately.

Turning off the light without fixing the problem does not make the problem go away. It simply overrides the light for a while until it’s back up again. 

In this article, we will go over:

• All the common causes for why the ABS light comes on
• How to fix them
• How much it’ll likely cost
• How you can turn the ABS light off with or without an OBD2 scanner

Let’s get straight to it!

Common causes for ABS light

Below is a quick table showing all the common causes for an illuminated ABS light and how much it’ll likely cost you to fix or repair.

Low Brake Fluid

The ABS sensor detects the level of brake fluid in the reservoir. Once it dips below a certain level, the sensor reports it to the module, illuminating the ABS light.

It’s a common occurrence for brake fluid to evaporate but there might also be a case for brake fluid leaks.

Look out for the following symptoms of a brake fluid leak:

• Oil puddle under the car
• Sponge-y brake pedal
• Issues with braking

If you have got a brake fluid leak, check the brake master cylinder for any visual hints of the leak. These are air-sealed containers and any leaks will be visible on the outside. 

Replacement of the brake master cylinder will cost you somewhere in the region of $100 to $300.

Sometimes it can be the brake line that requires replacing and replacement. See if there is a puddle of fluid under your vehicle. A spot of fluid leak under your vehicle points at a brake line leak which can cost $30 to $50 to replace. 

You can easily do that at home by pressing on the brakes hard to push out the fluid. It will help you locate where the leak is. Be sure to have a garage floor mat under your car when replacing the leak.

Once all the repairs are done, refill the brake fluid back.

Faulty Speed Sensor

Another common cause for an illuminated ABS light is faulty speed sensors. These sensors record information on the vehicle speed and send it to the control module where the system relays that information to the ABS system.

Where there are any irregularities in the speed of the wheels, the ABS adjusts the braking accordingly to avoid the vehicle from skidding or the wheels from locking.

You can easily replace the faulty speed sensor at home. It should cost you around $25 to $50.

Bad ABS Module

Your ABS module can malfunction due to corrosion or just general wear and tear. If that happens, you would need to replace it. The ABS module sends data to the central power unit and controls the braking system.

Depending on the vehicle and the model, replacing an ABS module can cost around $320 to $1,000. 

To replace the module, in most cases, you would need to get under the air filter. 

• Start by disconnecting your car battery
• Remove the air filter and any other component to get to the ABS module
• The module will have two wires connected to it. Unplug them
• Unscrew any bolts or screws holding the module into place
• Take the ABS module out and replace it with a new one
• Screw back the bolts and/or screws and plug in the two wires
• You’re done!

Some people might be uncomfortable taking on this DIY task, which is understandable. It is best to leave these things to a professional if you don’t know what you’re doing. Labor charges can range anywhere between $80 – $120.

Worn ABS Pump

An ABS pump pushes the brake fluid and activates the braking system preventing the vehicle from skidding. A worn hydraulic pump is the least common cause among the four, but if you’ve tried all the other solutions, then you should consider checking this out too.

Replacing the hydraulic pump is a labor-intensive task and requires a certain level of skill and knowledge. It is best to leave this to a professional as, after the replacement, you would also need a quick “service bleed”. For that, you would need to invest in the right equipment. Hence, we suggest that you rather head to a mechanic for replacing the hydraulic pump 

Depending on what kind of vehicle you own, a hydraulic pump replacement can cost you between $300 and $1,000.

How to get rid of ABS light without a scan tool?

Perhaps you’re looking to get rid of the illuminated ABS light and do not have a scan tool to do it. I don’t recommend doing that unless you’ve actually fixed the underlying issue first. Forcefully turning off the ABS light without solving the problem can negatively affect other components, in the long run, resulting in more expensive repairs or replacements.

Since you’re here to learn how to reset the ABS light without a scan tool anyway here are the steps to do a hard reset without using an OBD2 scanner:

1. Loosen and remove the negative battery terminal before doing the same for the positive side
2. Connect the two cables and attach them together using strong alligator clips
3. Leave them for 20 to 25 minutes. Make sure they don’t touch the battery terminals
4. Reattach the positive battery terminal first before doing the same for the negative terminal
5. Turn the engine on and the ABS light should disappear

How to get rid of ABS light with a scan tool?

Using a scan tool to reset your ABS light is a better alternative to doing it without one. An OBD2 scanner is an affordable investment for car owners as it helps read and clear fault codes for CEL (Check Engine Light), SRS (Supplemental Restraint System or airbag), ABS (anti-lock braking system), and more. The device can help users diagnose the problem without troubleshooting common causes helping them save time.

Although a scan tool does not fix the problem for you, it does let you know the specific issue your vehicle is facing so that you can repair/replace the component. 

Here is how you can get rid of the ABS light with an OBD2 scanner:

• Connect the OBD2 connector on your scan tool with the OBD2 port in your car
• Follow the instructions on your device to read fault codes
• Once it returns with the different fault codes, go back to the diagnostic menu and select erase codes
• Follow the instructions and select the system you wish to reset the fault codes
• You’re all done!

Why ABS light comes on and off?

One fairly common problem is the ABS light comes on and then goes back off for seemingly no reason. Most often, this is due to a sensor that is out of balance.

As you drive, the sensor may vibrate out of its proper place. When parking, it often resets. Sensors also gather dirt and road grime, which can reduce their efficiency over time.

Is it safe to drive a car with ABS light on?

An ABS light that is on means that you need to address the problem as soon as possible.

An illuminated ABS light in your car does not necessarily mean that you cannot drive the car. It is an indication that the antilock braking system isn’t working properly. This does not, however, mean that your brakes do not work at all. To avoid skids, the system keeps the wheels from locking while braking.

The ABS light being on means that only the ABS system may not work properly. This will be salient if you need to make an emergency stop.  You can still drive it, and the brakes themselves will still work fine, but with the understanding that ABS braking features specifically may not work.

What does it mean when both ABS and brake light are on?

Sometimes the ABS light and brake light will be on at the same time. This may indicate that there is a failing module in the antilock braking system. Low fluid is another reason that both of these lights may come on at the same time. The wheel speed sensor is another potential culprit for this problem.

Both lights on at the same time indicate a more serious problem which you should fix before continuing to drive. You should repair the braking system immediately because it is related directly to your own safety.

Bottom line

The ABS light is an added safety feature to alert drivers to any potential problems with the system. So, the light comes on for a number of reasons – from a lightbulb that needs replacement to a serious malfunction in the system.

Basic troubleshooting can help you determine exactly what the problem is and how to go about addressing it. The use of an ABS scan tool can dramatically simplify the process of diagnosis.