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Practice test 7 of 10

Louisiana CDL — Air Brakes Practice Test 7

The Louisiana 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.With the engine off, the parking brake released, and a fully charged system, the air pressure loss for a single vehicle should stay under what rate?
  2. 2.With manually operated tank drain valves, how often must you drain the tanks?
  3. 3.How do you test the service brakes as part of the final air brake check?
  4. 4.How does the emergency brake system stop a vehicle when the brakes fail?
  5. 5.What is the 'wig wag' low-air warning device?
  6. 6.In a dual air system, if one of the two systems gets very low on pressure, what happens?
  7. 7.On large buses, at about what pressure do the low-air warning devices commonly activate?
  8. 8.What is the purpose of a modulating control valve?
  9. 9.The safety relief valve in the first air tank is usually set to open at what pressure?
  10. 10.Why should you avoid pressing the brake pedal while the spring brakes are applied?

0 of 25 answered