Re: Battery drain on '87 5kS

[raf40@oes.amdahl.com (Richard Funnell)]

Chris,

>Anyways, back to the '87.  Yesterday we were using it to jump start another
>car (no, not an Audi  :) and the thing would almost die when we turned the
>ignition on the other car.  It didn't even have enough power to start the
>other car.  And the night before, we hooked up a battery charger to fully
>charge the battery, hoping that might do the trick.  Well, in the morning
>it started right up, and we drove to work, but a few hours later I went out
>to start it and...you guessed it - clicking noise.
>
>Anyone ever had this problem before?  Could I be looking at possible
>alternator and/or starter repairs?  Let me know if any of you have any
>ideas.  TIA...

The sure way to check this would be to check the alternator current output,
the battery current output, the charging voltage, and the drain current
flow when the car and all accessories are shut off.  The first two really
need a specialized tester since the current (amperage) is quite high,
although unless you bought a bad battery the battery output shouldn't be a
problem.  The charging voltage should read 13.5 to 14 volts, measured
across the battery when the car is running.  The last check can be done by
disconnecting either battery lead and putting a portable voltmeter, set to
read amps, between the battery clamp and the battery post.  You should see
only a few ma.

Guessing, it sounds as if your alternator may not be charging.  I would
expect a strong battery to be able to start the car even after a few hours
of a minor battery drain.  Since it always seems to start when you jump it
or charge the battery overnight, it doesn't sound like the starter.  You
might also look at the battery clamps to make sure they are clean and
getting good contact with the battery posts.  If they're not, it will start
when you jump it because the jumper cables are usually clipped to your
cables.  Good luck.


Richard Funnell,
San Jose, California
'83 urQ