Why is my car’s ABS light on?
If you own a car, you’ve probably seen your ABS light come on. But what does it mean? What causes the light to flash? Is it safe to drive with the light on? This post answers all these questions and more. Read on to learn everything you need to know about the ABS light.
What does the ABS light mean?
If the ABS light is on on your car’s dashboard, it means there’s a problem with your car’s anti-lock braking system. The anti-lock braking system (ABS) is a safety system that prevents the wheels from locking when you apply the brakes, and this warning alerts you that the system isn’t working as intended.
When you turn your vehicle’s ignition on, the ABS light will come on for one second while the system runs diagnostics. After this self-test, the light should go out.
If it doesn’t come on at all, you may have a burned-out bulb. On the other hand, if the ABS light stays on or comes on while driving, you’ll need to find out what’s causing the warning.
Causes of ABS Light
1. Speed ​​Sensor Fault
The wheel speed sensor detects how fast the wheels are moving and reports it to the ECU. With this information, the ECU can decide how to use the ABS. If the ECU detects that one of the wheels is spinning faster than the other, it will bleed more brake fluid, slowing the wheel down to improve grip on the road.
If the speed sensor stops working, the ECU doesn’t have accurate data. Note that this will not only cause the ABS light to come on, but it can also cause your car to lose traction when braking hard. In fact, it might even cause the traction control light to come on. The speed sensor is mounted very close to the wheel and measures how fast the wheel is moving. Its location close to the brakes makes it vulnerable to excessive heat and damage. It can also be damaged by metal chips and dirt from the brakes.
2. Bad ABS Tone Ring
The ABS sensor needs something to read the wheel speed, and that’s the ABS tone ring. ABS rings can rust or crack, causing the ABS sensor to give false readings. If this happens, the ABS light on the dash will come on.
Some ABS rings are built into the wheel bearing, which means the entire wheel bearing will need to be replaced. However, if they are attached to the drive shaft, you can often visually check for cracks or other damage.
3. Faulty ABS module or faulty wiring
The ABS module itself may be faulty. But the wiring itself may also be to blame. These cables are prone to corrosion, which can cause delays or no communication between the ABS module and the speed sensor.
It would be better if your car only needed a few cables. But if you’re unlucky, you’ll have to replace the ABS module, which will cost you even more. With either issue, you’ll notice your brakes no longer responding properly. You might only notice it occasionally at first, but it should get worse over time. You might also notice your brakes locking up or hearing a clicking noise.
4. Hydraulic Pump Failure
The ABS system needs to control the brake fluid flowing through a hydraulic pump. This pump is responsible for forcing brake fluid into the cylinders to be distributed to the brakes when the brake pedal is pressed. The ABS system also adjusts the brake pressure at each wheel based on speed sensor readings. With this information, it can direct the right amount of fluid to the brakes where it’s needed most.
Most of the time, this system works as intended. However, a hydraulic pump can fail or a valve in the hydraulic system can be defective. None of these situations are good. The pump is exposed to dirt and metal debris from contaminated brake fluid and can wear out. However, regular fluid changes can prevent this from happening.
If there is a problem with the pump, braking performance will be affected. The deterioration starts slowly and gets worse with disuse. If the master cylinder fails, the brakes will work well for a minute, but a second later they will completely fail, making driving very dangerous. In addition, a defect can cause a leak. When fluid leaks, the pedal is initially firm, then spongy, and eventually sinks to the floor.
5. Blown fuse
The ABS is activated by electrical components in the car. In fact, the ABS runs on its own fuse. These fuses are not invincible; a fuse can blow at any time and for no reason.
Fortunately, checking the fuse isn’t hard; in fact, if you don’t notice any symptoms other than the light on the dashboard, this may be your first diagnostic step.
6. Low Brake Fluid Levels
The ABS pump needs brake fluid to function properly. This fluid is forced through cylinders to supply the braking system. If you don’t have enough brake fluid, you’ll experience problems like your ABS light coming on.
If your fluid level is low, it’s important to find out why. Your fluid reservoir may be leaking, air may be in the brake system, or the seals may be damaged. Your brakes may also be worn out. If the pressure in the system is too low, the ABS module will not be able to equalize pressure between the individual wheels, causing slipping and skidding.
If your brake fluid level continues to drop, you may also have difficulty stopping. You may also experience increased noise when braking.
Diagnosing the ABS Light
1) Check the ABS fuse. This step only takes a few seconds and will save you a lot of trouble. It’s located in the fuse box under the dash. Consult your owner’s manual for a diagram showing the fuse location.
2) Check the brake fluid level. If the brake fluid level is low, top it off. If the fluid appears contaminated, drain the fluid and refill it.
3) Check the system for leaks. You should be able to see brake fluid leaking from under the car. New fluid will be pale yellow, while contaminated oil will appear slightly darker or even brown.
4) Test the ABS wheel sensor with a voltmeter. You can also read error codes with an OBDII scanner. This will tell you if there is a fault.
If you’re having trouble finding the problem, take your car to a qualified mechanic for further diagnosis.
How to Fix an ABS Light
Repairing an ABS light can cost anywhere from $20 to $1,000 depending on the issue that’s causing it to come on. We’ll take a closer look at the most common repairs to fix your ABS light, but before you start replacing parts, you should perform a full diagnosis to determine what’s causing the problem. After all, there’s no reason to put parts in your car that you don’t need.
The least expensive problem to fix is ​​a blown fuse. Not only will this repair cost less than $20, it’s also easy to fix. All you need to do is open up the fuse box and replace the fuse that activates the ABS. The next easiest solution is to top off your brake fluid if the level is low. This solution will only cost you the price of the brake fluid, unless there is an issue causing a leak.
From here, you can replace any faulty speed sensors or broken ABS tone rings. The average cost of this repair is between $100 and $300. This appears to be one of the most common issues for an ABS light. You may also need to replace the ABS module or rewire the system. It may be cheaper to fix the wiring problem, but a new module will probably cost between $200 and $600.
The biggest problem is having to replace the hydraulic pump or master cylinder. Replacing a master cylinder can cost between $300 and $600, but installing a new hydraulic pump can cost over $1,000.
Can I drive with my ABS light on? The short answer is yes, but it depends. This answer comes with a big warning: only drive with the ABS light on if you know it’s OK. Even if your braking system seems to be working properly, it can fail at any time if there is a problem. This is why it is important to take the ABS warning light seriously. You don’t want to end up stranded somewhere and have an accident.
We understand that you need to save money, and we also know that car repairs don’t always come at a time that is economically convenient. However, the costs you have to pay if an accident does occur can be immeasurable. Instead of taking the risk, we recommend that you scan for ABS codes and find out where the problem is right away.
How long can you drive with your ABS light on?
But even if you know how to drive a car without ABS, you should find out what the cause is. Take your car to a repair shop as soon as possible to have it diagnosed and repaired. Can a low brake fluid level cause the ABS light to come on? Yes. Low brake fluid levels can cause a loss of pressure in the ABS pump, which can put the Anti-Lock Braking System (ABS) into “fail-safe” mode. If this happens, the ABS light will come on.
Can I drive without ABS?
Driving without ABS is possible but not recommended. If you must drive without ABS, be sure to increase your braking distances and take extra caution in slippery conditions.
Can a weak battery cause ABS problems?
A weak battery could cause ABS problems, but it’s not very common. You will more likely find other malfunctions with your car first if your car battery is bad. However, if you’re having ABS issues, it’s worth checking your battery to see if it may be the culprit.
