On Thu, 11 Jul 2002, Rodney Woten wrote:

>  My van has a rotary battery switch to control its dual battery setup.
> It was installed by a previous owner in the cabinet under the sink.  The
> switch can select battery 1, battery 2, both or none.  Is this a genuine
> VW accessory, a Bosch accessory or some other aftermarket accessory???

I don't know about your particular van, but if it's a big red switch
with thick cables coming out of it the '75 I used to have had a
switch like that in the engine compartment.  It was an aftermarket
addition, I forget the name of the company but they make a lot of marine
electrical stuff.  On my van it was connected *directly* to the batteries,
and switched everything, including the starter and alternator.  I think
the idea is that you could set it to, say, 1 while parked, then if you
depleted that battery you could switch to 2, start the engine, then switch
to BOTH or back to the dead battery to recharge.  On cold days I
imagine you could also start with the switch in the BOTH position for
extra oomph -- it parallels the two batteries, doubling the available
current.  I never really got to try it because one of my battery trays was
rusted out, though I did use the switch to disconnect the battery when
storing the van or doing electrical system work.

Never move the switch to the OFF position with the engine running, you can
damage your electrical system.  (The voltage regulator will not work
properly without a battery connected.)  Also, if you only have one battery
connected, don't switch to BOTH unless you're sure the loose positive
cable won't short to anything.

             _ _
  __ _ _   _| | |  | David M. Brodbeck (N8SRE)              Ypsilanti, MI
 / _` | | | | | |  +-----------------------------------------------------
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