What releases the fifth wheel locking jaws so the trailer can be uncoupled? (You should make sure that it is in the engage position and the safety latch is in place.)
The release arm allows you to disengage the fifth-wheel locking jaws so you can uncouple the trailer. During your pre-trip inspection, check that the release arm is in the engaged position and the safety latch (if so equipped) is in place.
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