Skip to main content
DMV Test Free
ENES

Practice test 1 of 10

New Jersey CDL — Air Brakes Practice Test 1

The New Jersey CDL — Air Brakes knowledge test has ~25 questions; you need ~20 correct (80%) to pass.

This practice test follows that format: 25 questions, pass with 20 correct. Answer every page, then grade it to see the answers and explanations.

Questions 1–10 of 25

  1. 1.What is the purpose of an alcohol evaporator in some air brake systems?
  2. 2.When you test the low air pressure warning signal, before what pressure must it come on?
  3. 3.When should you avoid setting the parking brakes and use wheel chocks instead?
  4. 4.Where does the emergency brake system get the parts it uses to stop a vehicle after a failure?
  5. 5.Which type of foundation brake is the most common on air brake vehicles?
  6. 6.How are spring brakes held in the released position while you drive?
  7. 7.Why do air storage tanks hold more air than a single stop requires?
  8. 8.During the air-leakage test with the parking brake released and engine off, what is the maximum acceptable pressure loss for a single vehicle?
  9. 9.What does the air compressor governor control?
  10. 10.What should you never do when leaving your vehicle unattended?

0 of 25 answered