As many others may say ......
consider your ignition switch.
( I just fixed a 'classic' late model vanagon common failure - headlights
won't work except if you pull the stalk to get high beams .......
the wiring diagram ..............and 87 I think it was .........is difficult
to use or understand for the head lights, more than the diagrams for say, an
84 . Anyway ........
we had another ignition switch to try, plugged that in ..........and the
lights were fixed ! )

so ...do consider that part. It's really underbuilt on a vanagon.
if you have a spare one, or new one handy, it's easy to remove the plug
from the back of the ignition switch, and plug on the new one, and turn it
with a screw driver.
if that fixes it, it's a little more involved to replace the switch in the
steering column.  Remove steering wheel, the whole lock assembly, then you
can get to a small screw holding the electrical part of the ign switch into
the lock assembly.

voltage stabilizer in the dash pops to mind.
as do grounds !~ .........
there's a ground cluster above the fuse box, way  up in there. Those
commonly get weak, loose, or corroded.
Always check those and repair any bad ground wires there.

I'd test-fit a ignition switch first myself.
it's an inexpensive part, it's a part you want to have on board as a spare,
and just plugging in one is easy.
So small investment in energy and $ for a potentially big fix.
Worst case, you've got a spare ignition switch, which you should have
anyway.

the 86 and later Bentley light switch and head light wiring is illustrated
in such a weird and 'jump from here to there' way ........that I would just
re-draw that whole circuit for myself, to get a clear view of how it works.
good luck !
Scott
www.turbovans.com

----- Original Message -----
From: "Thomas Pfrommer" <pfrommer@PHAS.UBC.CA>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Sunday, July 26, 2009 6:17 PM
Subject: Electric problem in 2.1l

> Hi everyone,
>
> its been a long time since I am posting here, which is a good sign as it
> means the van is running (I am still following the list but can't really
> help to contribute). Well this is not the case any more and I hope I can
> get some good hints.
> Occasionally (and lately more and more often) suddenly the red water
> temperature warning light starts to flash, then the rpm meter shows
> weird behavior (not related to the engines rpm) and then the engine
> stops. The coolant temperature is not too high and also I have a full
> coolant tank. It seems to be connected to how much electrical equipment
> is running, hence if my head lights are on and I brake the described
> behavior occurs. Or if the radio is on and so on, .... it first came
> when I had the Hi-beam on on the highway to the Okanagan in British
> Columbia in the middle of nowhere .... luckily with the van you can just
> stop and sleep and wait for the next day to not drive with lights (I
> first thought about the light fuses).
> So I checked the fuses and all relays seem to be OK (I can't see any
> black locations that would indicate some failure).
> Hm, somewhere I have a bad connection but where and how can i find this
> out? And if I draw too much current a short happens and all is out,
> ..... at least thats what I think....
> Do you have an idea how I could carry on with testing to check where
> this problem comes from? I was looking at the wiring in the Bentley but
> could not come to one conclusive idea where this problem happens. The
> thing that the engine stops is hard to grep, as it could be the fuel
> pump the ignition system or something else, .... so I don't know at what
> wiring I should start, ....
>
> Thanks already for the help
> Thomas