Pennsylvania CDL — Air Brakes Practice Test

The Pennsylvania 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.

Pennsylvania 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
How are the powerful springs in spring brakes kept from applying while you drive?
Test 2
25 questions · pass with 20
In an s-cam brake, what happens when you press the brake pedal?
Test 3
25 questions · pass with 20
Where is the ABS malfunction lamp located on a trailer?
Test 4
25 questions · pass with 20
What is true about front-wheel braking on a commercial vehicle?
Test 5
25 questions · pass with 20
On a vehicle with an application pressure gauge, needing more and more pressure to hold the same speed is a sign of what?
Test 6
25 questions · pass with 20
Which statement about ABS is correct?
Test 7
25 questions · pass with 20
When should you skip setting the parking brakes and use wheel chocks instead?
Test 8
25 questions · pass with 20
What is a 'wig wag'?
Test 9
25 questions · pass with 20
A visible low-air-pressure warning must come on before tank pressure drops below what level?
Test 10
25 questions · pass with 20
In an s-cam brake, what happens when you press the brake pedal?