ABS Issue

ABS issues can be a real pain for a driver to diagnose, as there are no “tried and true” methods. All we can realistically do is check for the proper operations of the ABS, but even that is problematic since different ABS systems “report” issues differently. Some use a flash code system where the ABS light will flash a certain number of times for each issue, while others require a connection to a computer to display the issue(s).

Fortunately, all ABS systems seem to report proper operations in the same way. When the key is turned to the ON position, the trailer ABS light will illuminate for 1 to 3 seconds, then turn off. If there is an ABS issue, the light may flash several times, giving you the flash code, or it may just stay illuminated, meaning the codes need to be downloaded. In either case, the failure must be reported to your carrier at once.

There are a few things you can do to diagnose or resolve the problem. In the winter, it could be something as simple as frozen brakes. Try moving the trailer back and forth a few times and check your mirrors to see if any of the wheels are dragging. If so, use your hammer to pound on the brakes to release them and move the trailer back and forth again to see if that clears the code. If the brakes aren’t frozen but the code remains, drive around the yard for a few minutes. If the code clears, then the problem is likely a wheel speed sensor that detects a difference in speed between the wheels. Also, check the wiring from the wheel speed sensors. If they are broken, that will trigger an ABS fault.
If the issue is electrical, then a qualified professional needs to service the system. An ABS issue is not an out-of-service violation, but be aware that while braking performance is not compromised, a hard brake application on slippery roads could lead to a jackknife.

Don Taylor has been a professional driver since March 1985.  In 1994 he made the jump to driving tractor trailers, and has accumulated over 3.5 million miles, including over 4 years of driving turnpike doubles in Manitoba, Saskatchewan and Alberta.  He is currently hauling flat decks across North America.