Re: 635csi battery discharge

["Russ Maki" <rinard@xxxxxxxxxx>]

This was my experience with an E30; maybe it'll be of some help.

I had a current drain of almost 200ma tapping out my battery all the time. I
set up an ammeter in series between the negative  battery post and cable
clamp, and started pulling fuses. Imagine my puzzlement when I discovered
that no fuse had any effect on the current flow!

With the help of another lister, I eventually determined that some doofus PO
had installed a 40-amp relay in one of the auxiliary fan circuits where a
30-amp belonged. Resistance is lower through the control circuit of a 40-amp
relay than a 30-amp, which was apparently allowing a trickle of current to
flow through the relay from the autocheck system! That's my story, anyway,
and I'm stickin' with it. A proper relay solved the problem.

Bottom line: Rig a digital ammeter in series between the battery post and
cable to measure current flow. Remove fuses in the fuse box one at a time
and check the meter measurement. When the current flow dips, you've found
the guilty circuit. The owner's manual should tell you what accessories run
through specific fuses. If that fails, check the relays!

Russ Maki
Ixonia, Wis.


> Date: Wed, 2 Aug 2000 15:32:22 -0400
> From: Brouillette Jacques <jbrouillet@domain.elided>
> Subject: 635csi battery discharge
>
> Hey folks,
> My 635 discharges its battery if I leave it sitting for much more that 3
or
> 4 days.  This happens often as I travel frequently.  I wouldn't think that
> the computers "think" to much while the car is off, so what else could it
> be?
>
> Also, my stock radio has a ton of static when I change the volume up or
> down.  Has anyone seen this and fixed it?
>
> Thanks in advance,
> Jax

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