Battery Draw/Alarm system - 91 200 Avant

Steve Sherman spsherm at
Sun Jun 15 20:44:02 EDT 2003

Thanks to Bernie & Brett for their replies.

 I may have deciphered a bit more of what is going on.  It seems that it
is the aux vacuum pump that works the door locks that is drawing the 1A
of current.  If I wait long enough (15 min or so, wasn't waiting that
long before) the current draw goes down to 0.1A or 0.05A if the alarm
has actually locked the doors.  Double checked this by pulling  fuse 19
which powers the locks (per the fuse cover) and seeing the drop in current.

In my previous testing, I did not have one door closed all the way and
that caused the power locks to not work, which in turn seems to have
kept the aux vacuum pump active for some time drawing current.  A bit
odd, but it seems that if one does not actually use the power locks to
lock the doors (either with the alarm or by key), then this pump will
continue drawing power for 10-15min before it shuts off. It's not making
its noise all that time (up at 5A when you hear it) but it definitely
seems to doing something in the silence afterwards.

So, I am curious about this pump.  Is it normal for it to stay active
drawing 1A for 10-15min? What controls the logic for this thing?

In the mean time, I will be locking my doors, and getting a load test
for this batt.

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