(Updated on April 19, 2022)
Modern vehicles have what is known as an anti-lock braking system. The purpose of this system is to keep the driver safe by preventing the wheels from locking up as you apply the brakes. That way, you can keep control over the steering and your vehicle won’t skid as a result of the wheels locking up.
In addition, there is a warning light on the dashboard which will illuminate if there is any sort of problem with the anti-lock braking system. This is a light that you need to take seriously because it is an early warning sign that your braking system needs to be inspected right away.
What Does ABS Mean?
“ABS” stands for anti-lock braking system. When you step on the brakes hard, you are likely to lose traction on one or more tires. This is called lock-up. Tire lock-up happens when the friction between the brake pad and the brake rotor is greater than the friction between the tire and the road surface.
When your tires are spinning, you have better control over the car. You will also typically experience a shorter stopping distance. This is because a rolling tire has more grip than a sliding tire. The ABS system is designed to grab and release the brakes very rapidly at all four corners to prevent tire lock-up and keep each tire spinning, while still allowing you to slow the vehicle as quickly as possible.
5 Common Reasons the ABS Light Comes On
There are many causes which could make an ABS light come on. It doesn’t always mean there is a problem with the anti-lock braking system directly. There could also be a problem with other sensors or components that it communicates with as well.
Below are the top 5 causes of an ABS light coming on.
1) Low Brake Fluid
The brake fluid has a lot to do with controlling the braking pressure within an anti-lock braking system. There is a brake fluid reservoir which holds the fluid of the anti-lock braking system.
Sometimes there could be a leak from this reservoir which will cause the fluid levels to drop. Either that or excessive amounts of air may exist within the system.
Either way, it may certainly cause the ABS warning light to illuminate on the dashboard.
2) Faulty Speed Sensor
There are speed sensors built into every wheel’s hub which calculate the movement rate of that wheel. This information then gets transmitted to the anti-lock braking system.
If it turns out that at least one of the wheels is moving too slowly, the anti-lock braking system will increase the pressure of the brake fluid to allow the wheel to move at a normal speed.
But if there is a problem with the speed sensor, the anti-lock braking system will detect that and cause the warning light to illuminate on the dashboard.
3) Bad ABS Module
The module of the anti-lock braking system can form corrosion after a while. This is actually one of the most common reasons for why there ends up being a problem with the anti-lock braking system.
If the module is corroded, then it can’t obtain information from the wheel speed sensor. As a result, the ABS light illuminates on the dashboard. It doesn’t even take a lot of corrosion to cause this to happen either. But you will need to replace the module after this happens.
4) Bulb Check
Some vehicles will perform what is known as a bulb check on the dashboard. This check is for the driver’s convenience, so they know the bulbs of their vehicle’s warning lights are working properly.
These lights will usually turn off by themselves after a certain amount of time. In some instances, there may be a glitch in the bulb check which keeps the ABS warning light illuminated after the bulb check is completed.
5) Worn Hydraulic Pump
If there is one wheel of a vehicle that moves at a different speed than the other wheels, the wheel speed sensor detects this and then notifies the anti-lock braking system.
Once this happens, the system will activate the hydraulic pump to increase the amount of brake fluid pressure. This will allow the wheels to maintain their traction as they’re touching the ground.
Unfortunately, hydraulic pumps tend to get worn out after years of using them. This would certainly cause the ABS light to come on, which means you’d need to replace the pump right away.
What to Do When the Car ABS Light Comes on
When the ABS light activates on your car’s dashboard, it signals that something is wrong with the anti-lock braking system. That means if you need to step on the brake pedal quickly to stop your vehicle, then it might not stop as fast as you want it to. As a result, you could end up in a serious car accident.
Basically, the function of the anti-lock braking system is to keep your vehicle’s tires on the road as you aggressively step on the brake. That way, the wheels don’t lock up or skid uncontrollably on the road during the braking process. This is particularly important if the road is slippery or wet.
There are different reasons for why the car ABS light would come on. The main reason is from simply turning on your vehicle. After you put your key in the ignition and turn it on, the computer does a test on the anti-lock braking system to ensure it is functioning normally.
If the computer doesn’t find a problem, the ABS light will turn off quickly. But if the ABS light stays on, it means there is a problem with your anti-lock braking system.
Sometimes you might be driving, and the ABS light will suddenly come on too. In any case, you need to bring your vehicle to an auto mechanic whenever you experience this issue.
They are the only ones equipped to diagnosing the issue and turning which component of the anti-lock braking system needs repair or replacement.
Can You Drive Your Car With the ABS Light On?
Just because your ABS light is on, that doesn’t mean you can’t drive your vehicle. In fact, you will still be able to step on the brake pedal and slow the vehicle down.
However, your ability to perform a panic stop will be limited as you run the risk of locking the tires under heavy braking. Locking the tires increases stopping distance dramatically and prevents you from steering until the front tires regain traction.
What you need to do is drive carefully to the nearest mechanic after the ABS light comes on. Brake slowly when necessary but avoid braking quickly or aggressively. If you can do that, then everything will be fine.
The only circumstance where you shouldn’t even attempt to drive your vehicle is if the brake system light comes on when the ABS light is on. The brake system light indicates a much bigger issue with your braking system — a problem which may limit your ability to brake the vehicle at all. Therefore, you would need your vehicle towed to the mechanic if you notice both lights on.
How to Turn Off Your ABS Light
Most of the time, your ABS light will turn off automatically once the issue is resolved. If it does not, you should be able to use an automotive scan tool to delete the stored code and turn off the ABS light. If the issue has not been resolved, the ABS light is likely to return in the near future.