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Practice quizzes / Minnesota CDL Air Brakes Test Practice Questions - Minnesota Commercial Driver License (CDL) Air Brakes Knowledge Test Exam / Question 128513
Practice question

What happens when an S-cam rotates during brake application?

  1. It forces brake shoes outward against the drum
  2. It drains the wet tank
  3. It opens the fuel injectors
  4. It turns off the low-air warning

Answer: A — It forces brake shoes outward against the drum

The correct answer is shown above. Try the full quiz for additional practice.

Practice more: Minnesota CDL Air Brakes Test Practice Questions - Minnesota Commercial Driver License (CDL) Air Brakes Knowledge Test Exam →
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