Re: 4kq Battery Drain

[DeWitt Harrison <de@aztek-eng.com>]

OnThu, 17 Dec 1998 21:27:48 -0800 (PST), Todd Phenneger wrote:
>I seem to have a small problem.  Brand new battery, works fine on
>other car.  When I bought car it had a dead battery.  Charged it and would
>go dead in about one HOur sitting in car but I know battery was almost
>toast anyhow.  Put new battery from other 4kq in and works great.  Now,
>after a few weeks, it was dead tonight!!!  What gives.  My voltage meter
>in car reads about 13-14 volts when driving and Shucks put Alternator on
>tester and got 63amps at like 1,500 rpm.  That is about right isn't it?
>Seems to be as that is what my other car is.  So, Charging seems ok,
>Battery seems ok.   
>Worst case scenario?  I figure I have a short somewhere that is
>causing a slow power drain when parked and in the cold weather with the
>car only doing short trips it got drained fully over time.  A long trip
>would probably charge it back up again.  Does this sound feasable.  If so,
>where do I start checking? 

I think you are on the right track.

With a charged battery, i.e. after you've driven around for a while, disconnect
the battery ground strap and connect a current meter between the negative
terminal and ground. With all electrical consumers off, including the interior
lights, you should not see more than a few mA depending on the model. I
usually read less than 20 mA in my 88 5kcs. You will probably see something
more like a few hundred mA. Then pull all the fuses one at a time to identify
the circuit pulling the juice. (This will kill your radio programming, etc.
Sorry.)
Once you've got it narrowed down, you can start disconnecting the individual
items of equipment that live on the offending circuit.

DeWitt Harrison
Boulder, CO
88 5kcstq