You'll have to replace all of your rear bulbs at the same time. I have a 98 S70 and this was the solution. It was also the solution for my old 87 240DL. Your contacts are probably just fine. I think it has something to do with the age of the bulbs, and even if you replace the defective one with a newer one, the others don't synch right. You'll always get the bulb out light and the bulb will not work correctly.

Just count up how many bulbs you'll need and go to the auto parts store and get the correct ones. Put them all in, making sure not to touch the bulbs with your fingers, use a lint-free cloth. You won't have to worry about them for another few years. You shouldn't need to change the back-up lights though.


The Swede mobiles have personalities of their own.

FWIW our '98 S70 does exactly the same thing! I have read on this forum of another member fixing it by taking fine emery paper to all the contacts, using a spray-on contact cleaner and finishing by replacing all the bulbs. I have yet to do this on ours but I believe it is obviously a contact problem and will be fixed by the above procedure. The lamp at 'fault' on our car is called the 'fog' lamp, not the brake light and is located on the trunk itself.
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'98 N/A S70 133,000 Klm

I had this problem on my 98. I eventually replaced the brake light
bulbs. Comparing the new bulb to the old it looked like the
contact on the bulb wore down.

You could try swapping bulbs left to right and see if the problem
follows the bulb (mine did).

I have the same problem with my 850 every so often. So far I have removed and reset the bulb, cleaned the light housing contact and the bulb contacts to no avail. So far the last few times the bulb has gone I a gentle smack to the tail light bring the bulb back on.


Aaron

1997 850 n/a sedan
2001 V40 1.9T wagon