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Practice test 2 of 10

Tennessee CDL — Air Brakes Practice Test 2

The Tennessee 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 tell the driver?
  2. 2.At about what pressure does the governor let the compressor start pumping again (the cut-in pressure)?
  3. 3.What is a dual air brake system?
  4. 4.In an s-cam brake, what happens when you press the brake pedal?
  5. 5.In a dual air system, how quickly should pressure build from 85 to 100 psi when the engine is at operating rpm?
  6. 6.Where is the yellow ABS malfunction lamp located on a trailer?
  7. 7.On a long, steep downgrade, the braking effect of the service brakes should be treated as what?
  8. 8.With the engine off and the foot brake fully applied, what air loss rate is acceptable for a single vehicle over one minute?
  9. 9.A visible low air pressure warning must come on before tank pressure drops below what level on most vehicles?
  10. 10.What is the main job of an antilock braking system (ABS)?

0 of 25 answered