98 9-3 Flattens Battery for no apparent reason!

Shut the car off. Wait a few minutes for the interior fan to stop. Disconnect the battery positive cable and put an ammeter in the line between it and the battery. Look for a current draw. There will be a little at all times, but not much. Someone here can tell you how much is normal. Your's will likely be higher. Start pulling fuses until you find out what is drawing current.

hi, i`ve had a similair problem. the alternator charges fine but when left overnight it flattens the battery, if the rest of the electrical sysytem is ok , then more than likely a diode in the alternator has failed, they are devices which allow electricery go one way only , if they short , thay can flatten the battery., mark k

"Steve Shuttleworth" wrote in message news:_bSLi.50280$ snipped-for-privacy@newsfe5-win.ntli.net...

"Steve Shuttleworth" wrote in message news:_bSLi.50280$ snipped-for-privacy@newsfe5-win.ntli.net...

Yes, it is.

I don't know why... but they can clog up with crud, which makes the AAC think that the car is much warmer than it really is, then subsequently freeze you whilst driving along. :)

Normal is less than 50mA. If you find a current of 200mA or (in your case probably) more, measure the current that flows through every single fuse (while battery connected and car shut down) to find out which circuit is affected.

Looking at the manual you'll then have an idea which components might cause the faulty current.

/T.

Sorry, didn't read properly. Pulling fuses will do as well but might be a bit more inconvenient. /T.

Actually, I like your approach better than mine.

Thanks for all of your help guys. I tried all of your suggestions but to no avail. I have a strong suspicion that the little fan thing for the air conditioning has an intermittent fault and very occasionally doesn't shut down at all. Sometimes it runs for 20 seconds, sometimes for 20 minutes and sometimes for several hours.

As everything seems to work with the fan disconnected, that's the way it's going to stay.

Once again, many thanks.

Steve