Which of the following is NOT part of testing the tractor protection valve?
a) Pulling forward slowly, then applying the trailer brakes
b) Pressing the brake pedal sever times to release air
c) Charging the trailer's air brake system first
d) Shutting off the engine
Answer: a) Pulling forward slowly, then applying the trailer brakes
If the answers is incorrect or not given, you can answer the above question in the comment box. If the answers is incorrect or not given, you can answer the above question in the comment box.