[Vwdiesel] Cont'd Electrical gremlins - bad ground?

[Brett]

Hello,

I'm writing this as I wait for my battery to charge outside, had to call in
late for work. I posted a while ago about electrical problems, looks like
they are continuing. The problem is that my car is often losing the charge
at the battery. Went out this morning and the battery is putting out about
11.85 volts, not quite enough to crank it with a long glow plug cycle (I'm
in Southern Maine, it's cold enough all ready at 6:45 AM)
I had my alternator rebuilt at a  local shop a few weeks ago, so I'm going
to assume it's okay now. The alternator light has been lit up recently when
the engine speed goes up before I shift, then it goes off. I've been aware
of the problem, but figured I'd ask you guys for advice. I was just
searching the watercooled group, and saw a post from Loren in 2000 about a
possible bad ground causing this. I don't think anything should be actually
draining the battery, especially since I don't even have a radio in my car.
The alternator is putting out the proper voltage when it's running (right
around 13.9 volts). The battery is getting a proper charge when the car is
running as well from my multimeter testing results. I had the battery
tested and it is good according to the Autozone guy that tested it.

How many electrical grounds are there on an A2 Jetta? I should probably
clean them up. I recently replaced the starter -> positive battery terminal
cable with a low (2) gauge cable. I have a new 4 gauge cable to replace the
factory alternator -> starter cable. However, the battery ground cable is
original and the location where it anchors to the body is a little
corroded, all I've done is spray it with some Rust Check to try to keep it
from getting worse. I'm suspecting it's just a really bad ground not
allowing the battery to fully charge, but am not really sure. Any ideas?
Thanks in advance.

-Brett