Question

You are driving a combination vehicle when the trailer breaks away, pulling apart both air lines. You would expect the trailer brakes to come on and. 1. The tractor to lose all air pressure 2. The tractor protection valve to close 3. The trailer supply valve to stay open

Answer 1

The correct answer is 2. The tractor protection valve to close.

When the trailer breaks away, the emergency air line is severed. This causes the trailer brakes to come on and the tractor protection valve to close. The tractor protection valve is designed to prevent the tractor air tanks from losing all of their air pressure. If the tractor protection valve did not close, the tractor would lose all of its air pressure and the tractor brakes would come on. The trailer supply valve is not affected by the trailer breaking away.

Step-by-step explanation: