The ABS light on your dashboard serves several extremely important purposes. It turns on every time you turn it on. automobile, to let you know it’s still running and will turn back on if there’s a problem with your anti-lock braking system . In some cases, your ABS light may even flash trouble codes to help narrow down the source of the problem. In other situations, especially when more than just the ABS light comes on, it may be a warning that your vehicle will not be safe to drive until repairs are made.
What is ABS light?
The ABS light in your car or truck is a warning light that is specially attached to the anti-lock braking system. These lights are usually yellow, although in some cases they can also be yellow, orange, or even red. They usually look like the letters ABS surrounded by two circles, with the top and bottom of the outer circle cut off. In other applications, the light will consist solely of the letters ABS.
The anti-lock braking system, in turn, is responsible for pulsing the brakes under very specific circumstances. If the ABS system determines that your wheels are in danger of locking up, it is able to quickly activate and deactivate individual brake calipers or wheel cylinders .
The point of quickly pulsing the brakes is to avoid skidding because uncontrolled skid increases stopping distance and can result in a complete loss of directional control. In most driving conditions, this means that a functioning ABS system helps shorten the braking distance and also helps you control your car during an emergency.
If there are any problems with your ABS system that could prevent it from performing these functions, the ABS light will come on. Some issues cause the light to go on temporarily, while others cause it to stay on until the issue is resolved.
What causes the ABS light?
The two reasons for the ABS lamp to come on are to check the operation of the lamp or to alert the driver that some type of malfunction has occurred in the anti-lock braking system.
Some of the common reasons for the ABS light to come on include:
- Standard Lamp Test
- Low fluid level
- Faulty control unit
- Faulty speed sensor or wiring problems
- Faulty or defective pump
- Solenoid failure
What to do when your ABS light comes on
Because there are many reasons why an ABS light may come on, the best way to deal with the situation depends on a number of factors. For example, if you notice that the light comes on when you start your car and then turns off, you don’t need to do anything. This is commonly referred to as «checking the light bulb» and it’s done so that you know all the warning lights are working properly.
If you notice that your ABS light or any other warning light does not come on when you first start your car, you need to check if the bulb is burned out. Burnt signal lights must be replaced immediately. If a warning light, such as your ABS, has burned out, you will have no way of knowing when a problem occurs.
If the ABS light comes on while driving, it means that some type of malfunction has been detected in the system. It also means that the ABS system may not work properly if you find yourself in a panic stop situation, and you must act on the assumption that you cannot rely on the anti-lock brakes to help you stop or maintain control of your vehicle.
In most cases, it is perfectly safe to continue driving if your ABS light comes on. However, it is important to remember that there are several systems that rely on ABS to function. So that, if your ABS system is not working properly, you can’t be in able to rely on your traction control system stable control regulations, or other related them systems. That’s why it’s so important to pay attention to how your car handles and brakes, and to make an informed decision about whether to go to a repair shop or call for a tow.
ABS Components You Can Check Yourself
Most of the repair and diagnostics of the anti-lock braking system require special tools and knowledge that not always available to most drivers. However, there are a few things you can do with simpler tools, to help ensure your safety if you notice that the ABS light is on.
Some vehicles have a separate brake fluid reservoir for the anti-lock braking system, while others use a single reservoir. Either way, checking your brake fluid level is one simple thing you can do yourself. If the level is low, you can top it up yourself, but it is imperative to use the correct type of fluid and only use brake fluid from a container that has just been opened.
Safe Addition of Brake Fluid to the ABS System
Before adding brake fluid to your ABS reservoir or main reservoir, it is important to find out what type of fluid your vehicle uses. This information is usually printed or printed directly on the tank or on the tank lid. If it is not, you can find it in the owner’s manual or on the vehicle’s data sticker in the engine compartment.
Some types of brake fluids are not compatible with others, which is why it’s important to use the correct type. For example, if you fill your brake fluid reservoir with silicone-based DOT 5 brake fluid and your vehicle uses polyethylene glycol-based DOT 3 brake fluid, this could damage the internal seals or ABS components.
Along the same lines, adding DOT 3 fluid to a DOT 4 system can cause problems due to the lower boiling point of DOT 3 brake fluid.
The reason you shouldn’t use a previously opened bottle that has been sitting for a while is because brake fluid is hygroscopic. This means it will absorb moisture from the air and any moisture present in the brake fluid can cause the pedal to be soft and difficult to stop.
Performing Other Visual ABS Inspections
If you can locate and identify your ABS control unit and pump, you can check that they are tightly connected and that the electrical connections are not dirty or corroded. You can also check the ABS fuse.
Another thing you can check for yourself is that the wheel speed sensors are tight, connected, and free of contaminants. These sensors are installed in the hubs of each wheel so you can see the front ones more easily by turning the wheels left or right. The rear ones can be hard to see unless you’re driving with decent ground clearance.
Further diagnostics, such as checking the operation of individual wheel speed sensors, require special tools. For example, you can test a wheel speed sensor for an internal short with any basic ohmmeter, but a scan tool is extremely useful for checking the output of the sensors.
Checking ABS DTCs
In some cases, you can access ABS codes manually without any special tools. For this to work, the computer in your vehicle must flash the ABS light. The procedure usually starts by locating your vehicle’s data connector, which is the same connection used code readers and scanning tools .
Each car has its own way of manually checking for ABS trouble codes, so it’s important to find the correct procedure before attempting this. In many cases, you will need to use a jumper wire to connect two specific terminals in the data connector. This instructs the computer to enter self-diagnosis mode and the ABS light will flash.
By counting the number of times the ABS light flashes, you can determine the code or codes stored on the computer.
Although it is sometimes possible, reading ABS trouble codes with a scan tool is easier and less prone to accidentally finding the wrong code. Technically this is something you can do at home, but most ABS diagnostics and repairs are best left to qualified technicians.