Minnesota CDL — Air Brakes Practice Test

The Minnesota CDL — Air Brakes knowledge test has ~25 questions; you need ~20 correct (80%) to pass.

Or take one of 10 full-length practice tests

25 questions · pass with 20 correct. You get instant feedback and an explanation after every answer.

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The full-length test, with feedback and an explanation after every answer.

Minnesota CDL — Air Brakes practice tests

10 full-length practice tests, each with 25 questions and a pass mark of 20, like the real test. You see the answers and explanations after you grade.

Test 1
25 questions · pass with 20
Your brakes have gotten soaked driving through deep water. What does the manual tell you to do about it?
Test 2
25 questions · pass with 20
How should you test the service brakes during the final air brake check?
Test 3
25 questions · pass with 20
Which type of foundation brake is the most common on air brake vehicles?
Test 4
25 questions · pass with 20
Why is repeatedly pressing and releasing the brake pedal for no reason a problem?
Test 5
25 questions · pass with 20
Air brakes on a large commercial vehicle are actually made up of which three separate braking systems?
Test 6
25 questions · pass with 20
What is the purpose of a modulating control valve?
Test 7
25 questions · pass with 20
Before driving a vehicle with a dual air system, you should wait until the compressor builds at least how much pressure in both systems?
Test 8
25 questions · pass with 20
What most commonly causes air brakes to fade?
Test 9
25 questions · pass with 20
How often must you drain air tanks that have manually operated drain valves?
Test 10
25 questions · pass with 20
In an s-cam brake, what happens when you press the brake pedal?