CDL · Combination vehicles
You have just charged the trailer's air system. How do you verify that the lines were not crossed and that the trailer brakes respond?
Correct answer: Set and release the trailer brakes and listen to them work.
Answer options
- ASet the parking brakes using the control in the cab
- BSet and release the trailer brakes and listen to them work Correct
- CPress the brake pedal and check the trailer brake lights
Why
Shut the engine off so you can hear, then set and release the trailer brakes; you should hear the brakes move as they apply and air rush out as they release. Silence suggests the lines may be crossed.
About this question
Topic: Combination vehicles License: CDL
Part of these practice sets:
Where it applies: Asked in every state.
Practice the whole set
This question is part of Trailer Air Lines and Coupling (28 questions). Take the full set and check your score.
Practice Trailer Air Lines and CouplingMore questions from Trailer Air Lines and Coupling
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