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Question:
Having connected the air lines but before backing under the trailer, what should you do?
A
supply air to the trailer system and then pull out the air supply knob.
explanation
Make sure the trailer brakes are operational first. To lock the trailer brakes before backing beneath the trailer, either remove the red air supply knob (on newer vehicles) or move the tractor protection valve control to the emergency position.
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4 years ago
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4 years ago
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4 years ago
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