Weird. My 99 XC70 (115k miles) just stopped 2 days ago. Pulled off door panen and wire leads to motor. Checked voltage to motor hardness, had +12V when pushed door switch one way (remember to have the keys in) but got zero volts when flipped switch the other way. Took switch apart and cleaned brass contact points. Re-installed and worked perfectly. Doesn't take a lot of crud to break down the contact. Final cost: FREE just an hour of labor. Of course, next time it will go faster now that I know how to do it.

I agree with John. I had the exact same symptoms in my 98 XC (about 90,000 miles at the time) - rear windows would not work. Then, we noticed an electrical burning smell when using the driver's window, and all the windows quit. The nasty acrid smell came from the driver's switchpack.

Bought a new switchpack on eBay for about $80 or so. Popped the old one out (just stuck small screwdrivers around the edge and popped it out. I didn't remove the door panel. While I made a few marks in the plastic bezel around the switchpack, it was a very simple replacement, and I would definitely do it the same way again). Pulling the old unit apart, I found how the internal contacts had worn out and could see where the current was arcing, causing lots of black stuff and a bad smell.

I think the dealer wanted $150 or so for the part.

Good luck.

usually the culprit is the master switch at driver's door.
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'88 240, '92 745, '98 v70 -John, Tampa Bay