Question 10 of 20
Score: 0/0When testing the tractor protection valve, into which position should you move the red air supply control knob?
ExplanationTo test the tractor protection valve, pull out the red air supply knob to the emergency position. This closes the valve and activates the trailer emergency brakes.
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Did you know? Always do a tug test after coupling — the exam expects you to confirm the connection.
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