Battery Draw/Alarm system - 91 200 Avant

Brett Dikeman brett at
Sun Jun 15 17:12:09 EDT 2003

At 12:46 PM -0600 6/15/03, Steve Sherman wrote:

>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.

That is very, very high- typical parasitic load on most cars is
around a tenth of that.   Sounds like the door was open and the
lights were on, maybe?(there are, after all, 6 lights in the cabin
that are on with a door open- they add up.)

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

That's the only way you'll find the draw. Just pull fuses- don't
forget the radio will need its code again though.

By the way- the solar panels in various catalogs that you can put on
the dash(or on the back shelf) to keep the battery charged will do a
fine job of countering parasitic load and self-discharge of the
battery; typical units are 100-200ma.  The slow discharge causes
sulfating of the plates, and reduces the battery's capacity- it is
the #1 killer of lead-acid batteries.  The problem seems to be
aggravated in type 44's by the after-run circuit.

If you want to never replace a battery again, do a google search for
"lead acid battery faq".  It answers pretty much any question you
could have about lead-acid battery care.

Also, if you have a sulfated battery, there's a circuit that you can
build for about $20 in parts that can slowly correct it if it's not
too bad.  I've been meaning to build it for a couple months, haven't
gotten around to it yet.

"They that give up essential liberty to obtain temporary
safety deserve neither liberty nor safety." - Ben Franklin

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