Q
15. Why should you lock the tractor glad hands (or dummy couplers) to each other when you are not towing a trailer?
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AThe connected brake circuit becomes a back up air tank.
BIf you did not, you could never build system pressure.
CIt will keep dirt and water out of the lines.
Detailed Explanation
The correct answer is "It will keep dirt and water out of the lines.". This is based on federal CDL regulations and safety standards.
Correct Answer: It will keep dirt and water out of the lines.
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98. Charge the trailer air brake system and check that the trailer rolls freely. Then stop and pull out the trailer air supply control valve. Pull gently on the trailer with the tractor to check that the trailer emergency brakes are on.
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To test the trailer service brakes, you should:
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18. You have a major leak in the service line and you put on the brakes. Service air pressure will escape and cause the:
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To help prevent rollovers, you should:
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Using the trailer hand valve while driving:
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