So I just dropped my 2007 S80 back off at the dealership for a couple of repairs that were covered under warranty being that I've only owned it for a week, and when I dropped it off and handed over the Fob key, the Fob would unlock the vehicle every time properly... So they proceeded to replace the blower motor and resistor, as well as fix the front passenger inside door latch... Everything seemingly going well.... Well I came to pick it up after getting a text that it was done... And they handed me the Fob, but when I went to unlock the car the Fob literally did nothing whatsoever, I checked and the car was unlocked, so I went back inside and said "Hey, any idea why the Fob suddenly doesn't work anymore?" and they replied by saying "That's not on us he didn't ever even touch the fob, the batteries are probably just dead".... So I was able to start the vehicle just fine, zero issues there, and replaced the battery which didn't change anything... Any ideas?

 

Have you tried both your remotes? Do you have keyless entry? If so you might have a bad antenna. The remote sends a signal to an antenna mounted in the center of the car between the headliner and the roof. The range on my remote got smaller until it was 0 - no lock and unlock. My antenna was bad and a replacement solved it. You have to partially drop the headliner to get to it.

 

This is exactly what my S80 do. I got an used antenna and just replaced it (thanks to hoonk for the very useful description). But now there is no reaction to the Fob at all. Is there a programming of the antenna necessary?
Thanks!

 

No, it's plug and play.