Battery Draw/Alarm system - 91 200 Avant

Steve Sherman spsherm at
Sun Jun 15 13:46:45 EDT 2003

I've been trying to track down the cause of my "weak" battery.  The
symptom is that if I leave the car undriven for a few days the battery
is drained and has trouble turning over.  A week of no use, and I need a
charger to get it up and running again.  As long as it is driven every
day or two things are fine.

The local shop that offers a checkup for the batt and charging system
machine was out, so it will be a week or so til I can get that checked.
 But the charging voltage seems right (13.9v), so I tend to think the
charging system is OK..

I also checked the current draw from the batt after shutting off the car
and waiting long enough for everything to turn off (hopefully).  The
current draw was right around 1A, which seemed unreasonably high to me.
 However 1A constant draw seems like it would explain the slowly
draining battery over a few days time.

 I am thinking that it may be the alarm system.  The current was about
the same whether the alarm was armed or not (acutally a bit higher in
the unarmed state).  Unfortunately the alarm was put in 2 owners ago, so
I have no doc's nor any idea even where the alarm and its components are

Any input from listers that have an alarm, as to whether 1A draw is in
the ballpark or not  (and where do they
typically install the alarm stuff), as well as ideas of what other
things are likely culprits for drawing the batt down would be welcomed.

My next step is to try pulling fuses to see if I can fine one (or more)
that cut the current draw.


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