InspectionCâu 40 / 60
When performing an air brake check on a combination vehicle, why do you test the tractor protection valve and trailer air supply valve?
a.To grease the valves
b.To change gear ratios
c.To check the paint
d.To confirm that if trailer air pressure drops too low, the valves close and protect the tractor's air supply
Giải thích
The tractor protection valve and trailer air supply valve are tested to confirm they will close automatically when air pressure drops to a low level, typically between 20 and 45 psi. This protects the tractor's braking system if a trailer air line breaks. Confirming this function is a key part of the combination air brake check.
Luyện miễn phí toàn bộ 60 câu hỏi — không cần đăng ký.
Câu hỏi liên quan cùng chủ đề
- When inspecting the trailer's suspension system, what should you look for?
- What is the purpose of checking the trailer's air tank drain and slack adjusters during inspection?
- Why should you check that the trailer doors, cargo securement, and header board are secure during inspection?
- What should you check about the mounting of the fifth wheel skid plate and the trailer apron?
- During inspection, what should you check about the trailer's mud flaps and rear-end protection (ICC bumper)?
- When you check air lines during a combination inspection, which lines are you connecting and inspecting?
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