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Subject:Re: Is my auxillary barttery working correctly ?
From:Tim Demarest
Date:Thu, 29 Sep 2005 18:58:38 -0400

Check the connection of the small blue wire on the alternator... the 2
idiot lights (alt and o2) should come on when you turn the key on, before
the engine is cranked and running. If they don't the small blue wire is on
the wrong alternator terminal.

This same blue wire turns on the relay to connect the two batteries (the
fridge relay, in the stock Westie configuration). This wire should only
come up to 12VDC (ish) when the alternator is actually spinning. If this
wire is on a source that is always hot, then the aux battery relay will be
on *all* the time, and the alt light in the dash will *never* come on.

I had this mis-wired for over a year on my van, the aux-battery relay was
on all the time, so it was a constant load that discharged *both* batteries
if the van was parked. I got into that situation when I replaced my
original alternator with a FLAPS rebuild.. which had only one spade
terminal (to which I connected the blue wire). When that alt died (too soon
after installing it) I got a Bosch reman, which had two spade terminals...
but I put the blue wire onto the wrong one.

Once I corrected this, I got my alt light back on the dash (O2 light always
comes on with it, before I start), and it doesn't go out until I rev the
engine just a bit for the first time... and I can now park for weeks
without killing *either* battery.

Good luck,

Tim

>Just want to know if I did it right. First, the 2 idiot lights that alway
>stayed on when I first started the engine, dont stay on anymore-ever. Is
>this correct? Second, I disconnected the batteries, or tried to, to
>replace the altenator today.I got sparks when I disconnected the neg
>terminal of the cranking battery. Sparks when I then disconnected the
>positive terminal of the cranking battery. Then I got sparks when I
>disconnected the neg terminal of the auxillery battery.What the heck is up?