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Practice quizzes / NJ CDL Combination Practice Questions - New Jersey CDL Combination Vehicles Test Exam / Question 147978
Practice question

During a New Jersey tractor-trailer tractor protection valve review, what does the tractor protection valve protect?

  1. Disconnect the electrical cord
  2. Assume the fifth wheel is locked
  3. Use the parking brake while moving
  4. The tractor air supply

Answer: D — The tractor air supply

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

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