Skip to main content
DMV Test Free
ENES

Practice test 10 of 10

Washington CDL — Air Brakes Practice Test 10

The Washington 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 a trailer equipped with ABS, where is the yellow malfunction lamp located?
  2. 2.A manually operated tank drain valve should be opened how often?
  3. 3.What most directly causes brake fade on a long grade?
  4. 4.What feature is sometimes added to automatic tank drains for cold climates?
  5. 5.Air pressure has dropped far enough for the spring brakes to set on an empty rig or on a slippery road. What is the particular danger?
  6. 6.You are braking hard in a combination where only the tractor is fitted with ABS, and the trailer starts to swing out. What should you do?
  7. 7.When you press the pedal on an s-cam brake, what does the s-cam itself do?
  8. 8.On large buses, at what pressure do the low-air warning devices commonly activate?
  9. 9.On a newer air brake vehicle, how is the parking brake control usually identified?
  10. 10.How do air brakes differ from hydraulic brakes in how quickly they respond?

0 of 25 answered