First of all you should never disconnect the battery while the engine is
running. The battery is part of an engineered load and filter for the
alternator. Disconnecting while the alternator is producing current can
create a sudden voltage surge before the voltage regulator can react. This
surge is detrimental to the alternator itself and can damage anything
electronic including the ECU.

Yes something can be draining the battery. Yes, the battery can even be
defective. 4 months means little. Yes you can also have a wiring problem
between the battery and the alternator. Make sure the indicator
light-trigger circuit is working. If not the alternator may not always turn
on.

Dennis

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
randy velasco
Sent: Tuesday, November 29, 2011 8:43 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Something draining my battery

Hi All,

So this weekend while working on my 85 Vanagon I was not able to start the
van. Which is strange since the battery was only 4 months old. I jump
started the van and it ran for 20 minutes, After the 20 minutes I
disconnected the negative wire from the battery and the van shutoff. I
turned the van back on and disconnected the negative wire again and again
the van shutoff. Now I knew this could be the alternator. So I changed the
alternator and ran this test again and again the van shutoff.

I bought a voltmeter to test the battery and alternator and the new
alternator reading was 11.40 volts and the battery reading was 12.4 volts so
I knew the new alternator was not working properly. I reinstalled the old
alternator and tested and the reading was 13.98 volts which means the
alternator is working properly.So I went back to the battery and
disconnected the negative wire and the van shutoff.

Please help! What should I be looking for? Something is draining my battery.

Thanks

Randy