Question 13 of 20
Score: 0/0How do you test the tractor protection valve after charging the trailer air brake system and turning off the engine?
ExplanationTo test the tractor protection valve, you step on and off the brake pedal repeatedly. This reduces air pressure and should cause the valve to close, protecting the tractor's air system.
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Did you know? The back trailer of a set whips hardest — avoid sudden lane changes.
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