The tailgate latch on my 2000 V70 no longer locks/unlocks. I bought a new latch but when I plugged it into the harness it didn't work either. I am wondering if there is a reference to a wiring diagram for the tailgate latch.

Using crimp connectors might give future issues, but proper soldering, cleaning any flux off with solvent, and adding shrink wrap should lead to a repair that will last for the life of the car.

One problem is that some of the flux may wick into the wires away from the solder joint.

Had a similar issue on our 2000 V70 SE. The first sign of trouble was the license plate lights flickering when opening/closing the tailgate.

The tailgate (Volvo calls it a liftgate) wiring harness is routed along the interior upper left body and feeds all the of tailgate electrical functions: rear window defroster, power latch, rear wiper, license plate lights, upper brake light, etc.

There's a black plastic cable tie that secures the tailgate wiring harness to the upper left interior body roof area before it's routed into the tailgate through the left tailgate hinge. That cable tie was fitted too tightly during car assembly, it strains the wire harness with use over time, and the wire(s) chafe and break. No melted mess on ours, but that's possible if it goes unaddressed for too long.

Solution was to butt-splice and solder all of the chafed or broken wires (there are many wires in that harness), tape and rewrap the wire harness, and get rid of the cable tie to reduce wire strain. The rear left side interior trim panels need to be removed to access and splice the wiring harness and remove the cable tie.

Going on five years now with no repeat tailgate electrical issues.

Many Thanks. I will start that work this weekend and go for the harness repairing option.

I think I can handle the wire repair with no problems. Now, if I can get all those plastic panels off without breaking any of the mounting clips, that is a different story!

Your car does not have a REM. Check the fuses first, then check the wiring harness at the left rear hinge. It might be a melted mess.

https://www.youtube.com/watch?v=tcN33AotA8A


Also check that the license plate lights work.

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Keeping it running is better than buying new

This video exactly described the problem. Is this wire harness still available? If so does anyone have the part number? It seems replacing the harness might be the best solution. Crimping or soldering would work for a while but it seems like the other wires will also fail eventually.

Don't recall this harness being available the last time I looked, but it's out there now:

https://parts.smithvolvo.com/p/Volvo_2000_V70-24l-5-cylinder/Wiring-Harness-Boot-Lid-Bottom-Rail-Cable-Harness-Floor-and-Bulkhead-Trunk-Lid/42903428/9168056.html

Looks like it's a lot more harness than needed for the rear tailgate latch fix, but interesting to know that a 2000 V70 harness is available.

This company has helped me find hard-to-find parts before. Good service.

I'm sure that there is one, probably in Europe somewhere (the 2000 model equals the 1999 model in EU). But the wiring harness requires wire replacement to all of the functions in the rear hatch - lights, wiper motor, lock. There is no wire harness replacement just for the hinge area.

You are relegated to cleaning up the wires, crimping/soldering, and re wrapping the bundle. Just make sure the zip tie is not too tight, by moving the hatch up and down and watching the wire bundle move.

It's a pain, but if the weather is pleasant, not too bad.
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Keeping it running is better than buying new

Before splicing the V70 tailgate wires (see my other post), I tried to source a new tailgate harness. At the time, no 2000 V70 harnesses were available from Volvo or aftermarket. Harnesses are available for later V70 and 240. Haven't checked since then.

A new harness would be the best solution if available. A thorough splicing job seems to work, though.

It’s possible - maybe even probable - that the wiring has been severed and/or shorted to ground due to the tailgate hinge damaging the wire harness. There are plenty of prior postings that explain that one in detail. Also, I’m not sure if your model year has a rear electronics module (REM), but if it does you might check for blown fuses before delving into the harness issue.