Practice question

Spring brakes come on:

  1. When too much air pressure is lost.
  2. When a control on the dashboard is activated.
  3. When the tires have minimal tread depth.
  4. When the brakes are noisy.

Answer: A — When too much air pressure is lost.

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

Practice more: District Of Columbia CDL Air Brakes Test 2 →