Practice question

If you are operating a vehicle built before 1998 and are unsure if the trailer has an Anti-Lock Braking System (ABS), you can:

  1. Check for wheel speed sensors coming from the back of the brakes.
  2. Look for a red light on the front right corner of the converter dolly.
  3. Pump the air brakes to activate the ABS.
  4. Assume the vehicle has ABS.

Answer: A — Check for wheel speed sensors coming from the back of the brakes.

The correct answer is shown above. Try the full quiz for additional practice.

Practice more: Massachusetts CDL Combination Test 2 →