My wife just purchased an 2001 S80. The bulb failure message was on for the position lights. Turns out both tail lights and both side markers were not working. So I changed the relay under the dash and now they all work. But the dash is now completely blank, the climate system does work, and the power seats won't move. The car starts and runs fine, plus all the exterior lights work, even the blinkers (although the little light does not blink on the dash). I removed and then put back several other relays (trying to figure out which one was the position light) but I am fairly certain everything is where it was before.

Any idea what I missed or what I blew?

 

That sounds fishy you might want to try to have the codes read to see how many and what systems are affected.

 

Maybe the problems are unrelated. I just read in another post about control modules going bad when the battery dies. The car sat for a few days and I had to charge the battery after replacing the relay.

I searched the forum on replacing/resetting control modules but didn't see much. I have very little experience working on cars with computers (I drive an 81 Mercedes diesel wagon and a 72 Blazer). Is this something that a relative novice should be messing with?

If so, what advice do you have.

Thanks in advance.

 

Sad to say but the best thing might be taking it to the Dealer and have them check it over.

One guy had gotten away with the Dealer being able to install a software upgrade and that fixing it.