My testing yesterday was done by plugging the 5th wheel pigtail in to the receptacle on the truck.
The trailer itself, is sitting in the driveway. Besides it's regular front stands/jacks and rear stabilizers, it is on jack stands with the wheels removed so I could pull the drums and inspect the brakes, and repack bearings.
So there is no mechanical connection thru the kingpin/hitch.
The trailer itself, is sitting in the driveway. Besides it's regular front stands/jacks and rear stabilizers, it is on jack stands with the wheels removed so I could pull the drums and inspect the brakes, and repack bearings.
So there is no mechanical connection thru the kingpin/hitch.
While grounding will occur through the mechanical trailer connection you cannot depend on that.