Excuse my ignorance, but I just may have learned something.  Am I to assume,
gentlemen, that the 12v power option on the frig only works while the engine is
running?.....assuming, ofcourse, that I don't have an aux. battery?

....Phil in Bakersfield
'85 Westy

Bill Davidson wrote:

> > Bill:
> >
> > Yes - I think you are absolutely correct - the fridge draws more amps than
> > the wire from the alternator can supply - well ,actually it is just
> > following the path of least resistance.  If I am understanding the
> > schematics correctly, the fridge draws power from a 6mm wire directly from
> > the alternator (the feed circuit to the main battery) when there are no
> aux
> > batteries.
>
> No. I would expect your wire to be 2.5mm (per Bentley) unless you have a
> weekender that originally came with an auxiliary battery (then it would be 6
> mm per Bentley). The Westies imported into the U.S. did not come with an
> auxilary battery option so they did not wire them for that... Also, the
> alternator power does not go directly to the auxiliary battery unless
> someone changed the stock wiring... it goes: alternator> starter > starter
> battery > main fuse panel > under carpet between seats to auxilary battery
> box and fridge relay.
>
> Still, 2.5 mm wire is sufficient to supply the 7 or 8 amps to the fridge...
> unless there is something wrong with the wiring or the relay or the
> alternator..
>
> >With the aux battery setup, the shortest path to power becomes
> > the loop to the aux batteries, and they in turn are fed by the 6mm wire
> from
> > the alternator line.
> >
> > I think what is called for is some sort of diode to prevent the flow of
> > current from the aux batteries, or a relay/transistor that can switch the
> > fridge to the starting battery/alternator circuit when the engine is
> > running, and then switch back to the aux batteries when in "camp" mode.
> > This would essentially work the reverse of the existing relay.
> >
> > Does this all make sense?
>
> No. If the alternator is supplying enough power and the wires and relay are
> delivering it, the fridge will run off it and not draw down the auxiliary
> battery. I have a relay system and do no have the problem you are
> describing.
>
> You're assuming that your system is working properly but poorly designed...
> This is not the case. The relay system will work properly... there is just
> something wrong with the wiring or the alternator.
>
> Do the ammeter test I suggested in the previous post... find the problem.
>
> Bill
>
> >I'm pretty confident that the fridge is working
> > well, since I am not blowing fuses or creating weird puffs of smoke, etc.
> > :-)
> >
> > Brent Christensen
> > '89 GL Syncro Westy
> > Santa Barbara, CA
> >
> >
> >
> > ----- Original Message -----
> > From: Bill Davidson <wdavidson@thegrid.net>
> > To: Brent Christensen <bpchristensen1@home.com>;
> <vanagon@GERRY.VANAGON.COM>
> > Sent: Sunday, July 30, 2000 5:59 PM
> > Subject: Re: Running fridge with an aux battery
> >
> >
> > > Brent,
> > > Assuming that, like you say, the wiring is correct and the relay is
> > working
> > > properly ....
> > >
> > > My guess is that the fridge is just drawing more than is being supplied
> > > though the relay from your alternator... so it makes up the difference
> by
> > > drawing down the auxiliary battery...
> > >
> > > The stock wiring should easily supply the fridge since it was designed
> to
> > do
> > > so.... so what are the possibilities?....
> > >
> > > Could be you are drawing more than the 7 or 8 amps the fridge is
> supposed
> > to
> > > draw (perhaps other accessories... or even a short)...
> > >
> > > Could be the alternator is just not putting out enough juice to run the
> > > fridge and what ever else you are running off the starter battery
> > system...
> > >
> > > Both of the above?
> > >
> > > Easy enough to check... just use an ammeter in line between the
> auxiliary
> > > battery and  the relay... start the engine, turn on the fridge and wee
> > what
> > > the alternator is supplying.
> > >
> > > Bill
> > >
> > > Easy enough to test
> > > ----- Original Message -----
> > > From: "Brent Christensen" <bpchristensen1@home.com>
> > > To: <vanagon@GERRY.VANAGON.COM>
> > > Sent: Sunday, July 30, 2000 4:23 PM
> > > Subject: Running fridge with an aux battery
> > >
> > >
> > > > OK, just when you thought there could be no more written about this
> > > > subject...
> > > >
> > > > Here's a tricky one for y'all:
> > > >
> > > > I have a pair of auxiliary batteries wired up using the stock relay
> and
> > > > harness (yes, yes, they are wired correctly). The lead from the
> starting
> > > > battery attaches to terminal 30 of the relay, and the fridge and
> > auxiliary
> > > > batteries are attached to the two #87 terminals.  Everything works
> > dandy,
> > > > and has for over a year now, with one exception.  If I want to run the
> > > > fridge on 12v while underway, it now pulls from the aux. batteries
> > rather
> > > > than the alternator.  (I have found this to be empirically true, since
> I
> > > > have arrived at camp with the aux batteries drained down to 50% or so
> > > after
> > > > driving a couple of hours with the fridge set to 12v)
> > > >
> > > > After poring over the Bentley wiring schematics, this seems to be a
> > design
> > > > limitation.  (Needless to say, I drive around with the fridge running
> on
> > > > propane when going to a camp site)  Or am I missing something?
> > > >
> > > > Any brilliant ideas on modifying the wiring so that the fridge would
> run
> > > > from the aux. batteries while camped, but from the alternator while
> > > > underway?
> > > >
> > > > BTW, whatever solution I (we) come up with will be documented (with
> > > > pictures) on www.vanagon.com for the enjoyment of the community...
> > > >
> > > > Thanks!
> > > >
> > > > Brent Christensen
> > > > '89 GL Syncro Westy "Klaus"
> > > > Santa Barbara, CA
> > > >
> > >
> >
> >