Why Is My ABS Light on Semi Truck?

A semi-truck’s ABS (antilock braking system) light is an important indicator of the vehicle’s overall safety. If the ABS light is on, your truck is not functioning at peak efficiency and could be in danger of a breakdown. It is essential to understand why your truck’s ABS light may be on and how to address the issue.

The most common reason for an ABS light being on in a semi-truck is a malfunctioning wheel speed sensor. These sensors measure the rotational speed of each wheel and are integral to the functioning of the antilock braking system. If one or more of these sensors fail, they can cause the ABS light to come on and must be replaced as soon as possible.

Another potential cause for an ABS light being on in a semi-truck is brake fluid leakage. The braking system relies upon pressurized brake fluid to operate properly; if there is a leak somewhere in the system, it can cause pressure issues that could result in the ABS light coming on.

In some cases, corrosion or dirt build-up can also cause an ABS light to come on. Dirt or corrosion can interfere with electrical connections throughout the vehicle, including those that are part of the antilock braking system.

How To Diagnose An ABS Light On Semi Truck

If you notice that your semi-truck’s ABS light has come on, you will need to diagnose what could be causing it. The best option is to take your truck into a licensed mechanic or dealership who will be able to inspect all of its systems and determine what might be causing the issue.

A mechanic may need to perform diagnostic tests such as scanning the vehicle’s computer for any fault codes or checking for any loose wires or faulty parts that could potentially be causing the issue.

Conclusion


A semi-truck’s ABS (antilock braking system) light is an important indicator of its overall safety. Malfunctioning wheel speed sensors, brake fluid leakage, and dirt/corrosion build up are some common causes for why an ABS light may be illuminated. If your truck’s ABS light has come on, it’s important to get it inspected by a licensed mechanic as soon as possible in order to ensure your safety while driving.

Photo of author

Karen Watkins