Coupling & UncouplingQuestion 4 of 60
When connecting the glad hands, what must you check to avoid a dangerous coupling mistake?
a.That both hoses are the same color
b.That the hoses are as short as possible
c.That the tractor engine is running
d.That the emergency (red) and service (blue) lines are connected to the correct couplers, not crossed
Explanation
You must make sure the emergency and service air lines are connected to the correct glad hands and not crossed. Crossing the lines can leave the trailer with no emergency brake protection. Many rigs color-code red for emergency and blue for service to prevent mistakes.
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Related questions on this topic
- Before backing a tractor under a trailer, where should the trailer be positioned relative to the fifth wheel?
- What is the correct order for positioning the tractor before coupling to a trailer?
- Before backing under a trailer, the fifth wheel should be tilted how?
- After the kingpin has locked into the fifth wheel, how should you test that the coupling is secure?
- After the tug test, why should you go under the trailer and look into the back of the fifth wheel?
- When should the locking jaws be closed around the kingpin?
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