My 03 had the same sympton until it finally quit for good. My connector on the top side under the hatch was fried. Two of the conductors had shorted and corroded. The rest of the wires/contacts were ok.

My fix: I cut the two pair of wires off the connector and drilled 2 holes through the connector. I was then able to put each conductor through the hole and then splice the wire with a crimp connector. The wire was pretty heavy gauge (guessing power and ground), probably around 14/16 gauge. I put everything back together and slipped the rubber boot back on (Dawn dish soap can help lubricate it to slide it on easier). Everything works just great. Total cost $0.25 at most.