My position light burnt out so I bought a new one. I removed the old one and put the new one in the holder. When I placed it back into the socket, all the bulbs shorted out and stayed out. I removed the new bulb and cycled ignition, the bulbs that went out illuminated again. I placed the socket without the new bulb and the other bulbs stayed on. Now even when I place the old bulb in, the second the holder touches the socket, the other bulbs go out. I don't get it!

 

Having a similar problem: the fog lamp went out, and when I pulled it to look at it, there didn't seem to be a broken filament, so I greased it up and put it back. Now, all the lower lights on that side are out. Fuses are OK (natch; the passenger side bulbs all work) and connectors seem solid. Will try another complete bulb, but wondering if socket itself can 'go bad' somehow?

 

New bulb did no good...got out the manual again, turned to fuse page-- excuse me, pages--and double-checked the rear fog light fuse location. Yup, hadn't moved from yesterday, 10A, second one down, in rear of car on driver side. Still not blown, replace anyway, still dark.

So, if the fog bulb and the parking bulb (position bulb, in Volvo-ese) are the same, just one bulb with two filaments, you might think it had THE SAME FUSE? Nope. Try the fuse panel at the drivers door, another 10A, which it turns out only works driver side parking lights...hence, the pass side tail lights remaining on. It is blown. Bingo.

NOW, since it wouldn't be our Volvo without housing some gremlin, I get 'Alarm System Needs Burping' or some such message. Jeez...