The anti-lock braking system, more commonly known as the ABS, is designed to keep your vehicle’s tires from locking up when applying pressure to the brakes. It is possible to drive your vehicle without ABS, however, we highly recommend not doing so. Without the ABS, the braking system can lock up in emergency situations, cause skidding, and a loss of control while braking.
When Should the Light Be On?
It is normal for your vehicle’s ABS light to turn on for a few seconds or so when it is first starting up. This is when the vehicle’s ABS is checking itself to make sure it is working properly. After the check is completed, the light should turn off by itself. It is not normal if the light turns on or begins flashing in the middle of driving or stays on after the initial self-check. If this happens, safely and quickly locate your nearest mechanic to have your vehicle inspected.
Now that we have the basics out of the way. See below for the reasons as to why your vehicle’s ABS light may have come on and stayed on:
1. Brake Fluid
The ABS relies on the brake fluid for controlling pressure. Without the proper amount of brake fluid, the ABS can begin to fail. When the brake fluid is low, it can cause the light to come on. Reasons for low fluid could be that the fluid’s reservoir is leaking or there could be excessive amounts of air in the system.
2. Faulty Speed Sensor
The job of a speed sensor is to record the actual speed of each wheel and transmit this information back to the ABS. If one of the wheels is moving too slowly, the ABS will release more fluid to allow the wheel to move at a faster speed. However, if there is an issue with the speed sensor, the ABS light will come on to notify you. Reasons this can happen include damage from debris, road grime, or metal shavings from the brakes.
3. Faulty ABS Module
One of the more common reasons for the ABS light to come on is because of corrosion damage to the wiring of the ABS module. Corrosion damage means there is a delay or a lack of communication between the speed sensor and the ABS module. Worse case scenario is that the ABS module as a whole needs to be replaced. Best case scenario is the ABS module just needing rewiring.
4. Bad Hydraulic Pump
The ABS works in tandem with the speed sensor to control brake fluid. If the speed of one of the wheels is off, the ABS will either lower or raise the pressure to correct its speed. Over years of regular use, pumps tend to normally wear out. Once this happens, it is imperative to have it replaced.
5. Blown Fuse or Stuck Bulb
If the light comes on and your vehicle doesn’t have any of the symptoms mentioned above, it could be a glitch in the bulb check. This may be a glitch or more commonly, a blown fuse. Sometimes a blown fuse to the ABS can cause the light to come on and stay on. Fuses are easy to blow, so sometimes it’s an easy fix to check.