Practice question

What is the purpose of checking the tractor protection valve and trailer emergency brakes during air brake tests?

  1. To verify the system protects the tractor and applies trailer emergency brakes when supply pressure is lost
  2. To measure cargo weight
  3. To test the power steering pump
  4. To prove the electrical cord is connected

Answer: A — To verify the system protects the tractor and applies trailer emergency brakes when supply pressure is lost

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