Like Nick said, if you have a 5 flat plug, you can plug the blue wire on the trailer side into one of the other wires on the truck side & it should get you by.
You can also use a 1/2" nut & put it in the slot so the plunger can't move backward. Use a piece of duct tape to hold it there.
(Message edited by bill_airjunky on August 05, 2009)