So this weekend I was faced with the dreaded "tailgate ate my wire harness" issue, which manifested itself to me on Friday by turning the rear wiper when I hit the brakes.

First off it was a stupid stupid stupid stupid design by Volvo. Every other car company ether had the wires for their wagon hanging down inside the cargo area or put the wires through the tailgate nowhere near the hinges.

I had read stories on this forum and other forums where the people doing this repair loosened the hinges to pull the wire through and redid the wiring. But knowing my luck I go to remove the hinge and it falls apart and there are no wagons in the junk yard.

So my plan was to simply cut out the bad section and rewire it, I read about the fact the wires were glued to the track in the hinge but on my car there was no "glue" as the slipped out with a gentle pull. I also read about the harness from IPD you could buy but I would have to be nuts to struggle running that harness back into the hinge and have it get eaten by the hinge in a few years(I like doing a job correctly and once)

I decided to simply extend the wires(with extra wiring and crimp connectors with shrink tubing) and run them into the cargo area instead of the hinge. I noticed the hinge ground was broken also(which would have meant I needed to replace the hinge(F that) )

I started by running 2 ground wires to the tailgate. I first wanted to run the grounds through the the same hole as the harness in the tailgate but was prevented from doing so by the tailgate design. I then removed the 3rd brake light and ran the ground wires through the grommet that the wires from the 3rd brake light came through and attached them to bolts that held the wiper motor to the tail gate. I then routed the wires though that black plastic shrouding/molding that covers the inside of the rear window(what the 3rd brake light is mounted to) and ran it back to the top of the tailgate and ran it into the car. I then drilled 2 holes into the body of the car(near the wire harnesses) and attached the ground wires to screws.

I tested it and all functions work when the tailgate is opened and closed so success!!!

The result was a large wire harness on both sides that have plenty of slack when the tailgate is open.

Yes it looks odd and a bit ugly BUT I value function over form and can live with these unsightly harnesses in exchange for not getting pulled over and ticketed for non functioning tag lights or 3rd brake light.

Also I was not able to put the headliner back on fully due to this but I did the best that I could and that was fine enough for me

Here are some pics


With the tailgate opened



With tailgate closed