Coupling & UncouplingQuestion 23 of 60
Why must you supply air to the trailer and check for air leaks before moving after coupling?
a.To cool the engine
b.To inflate the tires
c.To confirm the trailer brakes work and the air system holds pressure before driving
d.To lower the landing gear
Explanation
After connecting the air lines you must supply air to the trailer and check that the system holds pressure and the trailer brakes operate. Listening for leaks and watching the gauge confirms the braking system is sealed. Driving with a leaking or unconnected trailer air line can leave you without trailer brakes.
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Related questions on this topic
- What should you check about the fifth wheel plate before backing under a trailer?
- Before coupling, why should you inspect the area around and under the trailer?
- Which of the following is the correct sequence when coupling a tractor and trailer?
- What is the purpose of the safety catch on many fifth wheel release levers?
- If the trailer is too low when you back under it, what is the likely result?
- When should you chock the trailer wheels during coupling or uncoupling?
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