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Practice test 7 of 10

New Hampshire CDL — Air Brakes Practice Test 7

The New Hampshire 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.On older vehicles, the manual ties the low air warning to the compressor governor instead of to a fixed 55 psi. If such a vehicle's governor cuts out at 120 psi, when must the visible warning come on?
  2. 2.For the front of the vehicle and engine area on the vehicle inspection test, the manual explains why you look for air leaks. What could an air leak point to?
  3. 3.Which of these Step 7 checks does the manual have you run with the engine shut off?
  4. 4.Driver A's CDL carries the L restriction and Driver B's carries the Z restriction. Going by the manual's definitions, which of them may operate a commercial vehicle with air over hydraulic brakes?
  5. 5.The manual lists what puts the L restriction, no air brake equipped CMV, on a CLP or CDL. Which of these is NOT one of the triggers?
  6. 6.Why does the manual say an air brake system includes a stop light switch?
  7. 7.A straight truck's air leakage is checked both ways with the engine off. With the brakes released, the gauge falls 2.5 psi in one minute. With the foot brake held fully down, it also falls 2.5 psi in one minute. How do those results compare with the manual's limits for a single vehicle?
  8. 8.The manual calls hitting the brakes a good response when someone suddenly pulls out ahead of you, but only under two conditions. What are they?
  9. 9.Each time you let up on the brake pedal, some compressed air leaves the system and tank pressure drops. What does the manual say makes up for the lost air?
  10. 10.You are testing the low pressure warning signal with the engine off and the electrical power on. Pumping the brake pedal, you watch the gauge fall to 50 psi before the warning finally comes on. What does that tell you?

0 of 25 answered