InspectionQuestion 43 of 60
When you check air lines during a combination inspection, which lines are you connecting and inspecting?
a.Only the fuel line
b.Only the electrical line
c.The service (blue) air line and the emergency (red) air line
d.The coolant and oil lines
Explanation
On a combination vehicle you inspect and connect the service air line, often blue, and the emergency air line, often red. The service line carries air for normal braking, and the emergency line supplies the trailer reservoir and controls the spring brakes. Both must be secure and leak-free.
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Related questions on this topic
- 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?
- When performing an air brake check on a combination vehicle, why do you test the tractor protection valve and trailer air supply valve?
- 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)?
- Why is it important to check the trailer registration, load limits, and that the trailer is not leaking (for tankers or vans) during inspection?
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