Practice question

A tractor-trailer loses 5 psi in one minute with the service brakes fully applied and the engine off. What is the result?

  1. It fails because the combination applied limit is 4 psi per minute
  2. It passes because applied brakes may lose unlimited air
  3. It passes because trailers are exempt
  4. It only tests ABS

Answer: A — It fails because the combination applied limit is 4 psi per minute

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