Question 10 of 20
Score: 0/0When coupling a tractor to a semi-trailer and after connecting the air lines, what should you do before backing under the trailer?
ExplanationBefore backing under the trailer, you must supply air to the trailer and then pull out the air supply control to set the trailer brakes. This prevents the trailer from moving unexpectedly.
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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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