Question 17 of 20
Score: 0/0To test the tractor protection valve, after charging the trailer air brake system and turning off the engine, you should:
ExplanationAfter charging the system and turning off the engine, pressing and releasing the brake pedal several times helps verify the tractor protection valve is working properly.
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Did you know? Know which line is supply and which is service, and what happens when the emergency line loses air.
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