First note, seems like after reading hundreds of posts on these forums over half of them start out with something like: the wife’s Volvo, or my GF’s Volvo, or my friends Volvo (she’s been having problems.) I just want to know why these people don’t want to own the cars, or what makes them feel the need to clarify that the car is the “wife’s.”
Anyway, my wife’s Volvo is having the oddest problem. She bought a 96’ 850 GLT sedan 2.5 automatic, and there has been one problem that seems to allude. The battery dies…I have read many posts in the 850 section of this forum relating to battery, alternator, or similar but nothing seems to be the same so I offer you my problem in a hunt for the truth.
The battery died in her car about a month ago, and we jumped it, tried to charge it, but it was no use. The new battery we purchased went strong for three or four days then kaput. Now it seems like every third or fourth time the car is driven it ends up dead next time we go to start it. Sometimes it’s only three hours and its dead, sometimes it goes a couple days and starts fine. I have checked the glove box light, and checked the trunk light.
The other problem is the factory alarm. It has never worked that we are aware of, but the remote key fob does lock and unlock just fine. The problem is that while driving, the alarm horn (the one next to the firewall) starts honking randomly.
Does any of this sound familiar? I was thinking alternator, alarm relay, or possibly a bad switch in the alarm system. Is there a way to just kill the alarm without destroying any other function of the car?
Any help is greatly appreciated.

 

Can't lay the blame on my wife, she doesn't drive.

Try pulling the alarm relay. It's #14 in the Central Electrical Unit. I don't know if this will cause problems with the immobiliser which is related to the alarm function.

 

thanks bill, i'll try it tonight when my wife gets home from work, should have tried that earlier now i'm hitting my head in the foot with my...

 

Have you checked for a parasitic draw?

 

I was thinking exactly the same. Post how many milliamps are drawn from the battery after 15 mins of removing the key and turning everything off.