Volvo Repair: Volvo S70 1998 electronics problem (sudden shut-off and dead battery), volvo s80, volvo s70 1998

Question
Hello James, I sent you this question about a couple of weeks but I guess you didn't receive it. So here it is again. I have a 1998 Volvo S80 with 90k of mileage. And It seems like there is a problem with electronics. About two months ago the started behaving like the battery power is leaking (when I started up in the morning all the lights would be dimmer). So, after a while the battery started getting dead once in 1 week approximately. So, I replaced the battery and the first couple of weeks it was fine. But then the car started to shut off while I'm driving. It would start up right again with the key though. So decided to put it into garage for 1 week and to do some research on the problem. In one week when I decided to start it up, the new battery was dead again.

Any help or suggestions would be very much appreciated.

Dmitry.


Answer
First I'm sorry that I wasn't able to reply sooner.  I, in fact, did not get that question before.  

One thing that I would suspect is something in the charging system.  It sounds like you are getting intermittent charging from the alenator causing the car to run off of the battery at times until it is dead or low.  It could be a combination of 2 problems though because if it was to die while driving it wouldn't usually start right up again.  


It could also be a computer malfunction.  Usually batteries dead when trying to start the car were either dead when you stopped the car (never charged properly) or were drained overnight.  An intermittent computer problem could explain those symptoms all together but it seems very unlikely.  

Your best bet for finding the problem is to let a good shop or dealer look at it.  Don't take it to Wal-mart or a tire/battery place because they'd be chasing the problem for days or just sell you parts without knowing if it will fix the problem.  Hope that helps.

James