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Practice quizzes / Illinois CDL Air Brakes Practice Questions - Illinois CDL Air Brakes Knowledge Test Exam / Question 99539
Practice question

What is a wig-wag in an air brake system?

  1. A type of S-cam
  2. A mechanical low-air warning arm that drops into the driver's view
  3. A trailer parking brake valve
  4. An automatic slack adjuster

Answer: B — A mechanical low-air warning arm that drops into the driver's view

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

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