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Practice test 2 of 10

New Jersey CDL — Air Brakes Practice Test 2

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 does a supply pressure gauge on an air brake vehicle show the driver?
  2. 2.If the air compressor has its own separate oil supply, what should you do before driving?
  3. 3.Before the air pressure in the tanks drops below what level must a visible low-air-pressure warning come on?
  4. 4.On a newer air brake vehicle, how do you apply and release the parking brakes with the diamond-shaped yellow knob?
  5. 5.Why do air storage tanks hold more air than a single stop requires?
  6. 6.When you test the low air pressure warning signal, before what pressure must it come on?
  7. 7.During a walk-around inspection, how much movement in a slack adjuster suggests the brakes need adjustment?
  8. 8.How is the air compressor typically driven by the engine?
  9. 9.On a trailer, where would you look for the yellow ABS malfunction lamp?
  10. 10.Why does a heavily loaded vehicle take a long distance to stop once the spring brakes come on from low air pressure?

0 of 25 answered