Q
20. The driver crosses the air lines when hooking up to an old trailer. What will happen?
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AIf the trailer has no spring brakes, you can drive away, but you will not have trailer brakes.
BThe brake pedal will work the trailer spring brakes instead of the air brakes.
CThe hand valve will apply the tractor brakes instead of the trailer brakes.
Detailed Explanation
The correct answer is "If the trailer has no spring brakes, you can drive away, but you will not have trailer brakes.". This is based on federal CDL regulations and safety standards.
Correct Answer: If the trailer has no spring brakes, you can drive away, but you will not have trailer brakes.
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