Georgia Commercial Driver License Practice Test

What is the recommended way to confirm that a trailer has ABS?

1. Look for wheel speed sensors coming from the back of the brakes

2. Inspect the trailer for visible ABS lights

3. Examine the trailer's braking record

4. Test drive the trailer with ABS engaged

The correct answer is: Look for wheel speed sensors coming from the back of the brakes

To confirm that a trailer is equipped with Anti-lock Braking System (ABS), the recommended method is to look for wheel speed sensors that are typically installed at the back of the brakes. These sensors are integral components of the ABS and play a crucial role in monitoring wheel speed to prevent wheel lock-up during hard braking. Wheel speed sensors send information to the ABS control module, which uses that data to modulate brake pressure, helping to maintain vehicle control during braking scenarios. The presence of these sensors is a strong indicator that the trailer is equipped with ABS. While inspecting for visible ABS lights can be informative, those lights usually indicate that the ABS is functioning properly or may signal a fault, rather than confirming the presence of ABS itself. Examining the braking record may provide historical data about the trailer's brakes but does not offer direct confirmation of ABS installation. Similarly, test driving the trailer with ABS engaged can demonstrate that the system is operational if it is present, but it does not confirm its existence in the first place. Therefore, the most direct and accurate method is to check for those specific wheel speed sensors associated with the ABS.