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Practice quizzes / NC CDL Combination Vehicles Practice Questions - North Carolina CDL Combination Vehicles Test Exam / Question 137600
Practice question

If the trailer air supply pops out because pressure drops too low, what is the immediate trailer-brake effect?

  1. Trailer emergency brakes apply
  2. Trailer service brakes release permanently
  3. Landing gear lowers
  4. Fifth wheel jaws open

Answer: A — Trailer emergency brakes apply

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

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