Drain on Battery 1997 850 GLT

graydawn · Post by **graydawn** » 17 Aug 2009, 06:08

I have a 1997 850 GLT wagon and over the last 4 days my battery has been drained over night three times. Not sure what might be causing it. Any suggestions as to where to start to look. The last two times I have gone out to see if I could hear or see anything running. but no luck!

Thanks

Hutch

FCPEURO · Post by **FCPEURO** » 17 Aug 2009, 09:00

How old is the battery? It could just be old and not holding a charge anymore.

sunstate850owner · Post by **sunstate850owner** » 17 Aug 2009, 11:56

I was actually preparing a post for the same issue with my 1995 850. I just replaced the battery today so we'll see what happens, but, when I put a meter between the neg cable and the neg battery terminal I get .3 amps and full voltage. nothing is on in the car except the alarm system. I pulled each fuse one at a time with no change in the meter readings. I have no idea if the readings are "normal" on not. Does anyone know?

Post by **Ozark Lee** » 17 Aug 2009, 12:03

Welcome to MVS,

The book maximum is stated as "not exceed .3 amps". In reality it should be closer to .1 amps.

...Lee

goober4321 · Post by **goober4321** » 17 Aug 2009, 22:52

Here is a simple solution for this problem if you follow these steps........

1. Take an ordinary 12V test light
2. Remove the positive battery cable
3. Place the test light between the positive terminal of the battery and the positive cable
4. If the light on the test light lights up you have an offending circuit pulling power.

Here is the cool part.....................
5. Start pulling fuses till the light goes out
6. Read what the "light out" fuse circuit controls

WALLAAAAAAA..................................
You found your problem. Fix the issue and you are done and the light on that circuit should go out.

sunstate850owner · Post by **sunstate850owner** » 18 Aug 2009, 08:54

thanks for the suggestion but I've already done that. I used the negative cable and a meter instead of the positive cable and a test light, but there shouldn't be any difference. I had no response from pulling each fuse one by one. the meter remained a constant .3 amp drain. doesn't make a lot of sense to me because I agree that one of those circuits should have been the culprit.

goober4321 · Post by **goober4321** » 18 Aug 2009, 09:39

trust me you have to use the test light and the positive cable. I had the same issue on my 97 T5 not that long ago and it turned out the bad circuit was the glove box light being "on" due to the door not turning it off.

sunstate850owner · Post by **sunstate850owner** » 18 Aug 2009, 11:54

ok, I'll try the positive cable and report back. thanks

goober4321 · Post by **goober4321** » 20 Aug 2009, 16:30

Just curious as to if you had any luck.

Volgrrr · Post by **Volgrrr** » 20 Aug 2009, 23:28

The reason for putting the test implement on the positive side is simply this.

Placing the test implement between the positive pole of the battery and the positive battery cable means any current flow leaking to earth (i.e. neutral) has to pass through the test implement.

In a perfect world you should be able to do exactly the same test using the negative side however, earthed connections are notorious for developing open circuits due to loose, broken or dirty connections.

Because the vehicle chassis acts as a common negative pathway that allows current flow to return to the battery, any poor connection creating an open circuit will act, obviously, like a switch, i.e. cutting off current flow, and the test implement will not register any current flow under these conditions.

So, by testing on the negative side of the battery, you are putting all your eggs in the one basket based on the premise all the earthed circuit connections are 100% sound.

I hope this may be of some assistance to you.