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Practice quizzes / LA CDL Combination Practice Questions - Louisiana CDL Combination Vehicles Test Exam / Question 115279
Practice question

What should happen if trailer supply air is lost?

  1. Trailer service brakes strengthen forever
  2. Trailer spring brakes apply as emergency brakes
  3. The fifth wheel unlocks
  4. The electrical connector seals the leak

Answer: B — Trailer spring brakes apply as emergency brakes

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

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