This sounds like a classic grounding problem.One of the lights IS getting a ground, so the light that is not is "borrowing" that ground, and running its power through TWO light bulbs to get to ground. That is why the lights are dim, they are now at 6 volts each. It has created a series circuit out of what should be a parallel circuit. This can happen when the grounds from each light bulb / socket are making contact to each other, but not to chassis ground. The power can go back through any part of the circuit that is not energised to get back to ground. Bulbs with more than one filament are especially good at this trick, because they are already "sharing" a ground between the two different filaments.
The power path will not be going directly to ground but instead chasing through several cicuits, wereverthere is less potential, before going to ground. And remember, all these lights connect at the switch, so for example, the left rear running light COULD be supplying the ground for your mis-behaving front left turn signal...

Kevin <vwfixer@CENTURYTEL.NET> wrote:
Hi Frank,
It just got a little stranger. Now the drivers side driving light is on all
the time dim on low beam bright on high and on the passenger side it is just
always dim but will now stay on with the high beams on. I'm also still not
getting the indicator light to work.
Any one have a guess?
Thanks
Kevin .
-----Original Message-----
From: RAlanen@aol.com [mailto:RAlanen@aol.com]
Sent: Friday, November 11, 2005 2:58 AM
To: vanagon@gerry.vanagon.com
Cc: vwfixer@centurytel.net
Subject: Re: Still no passenger side high beam

In a message dated 11/11/2005 12:09:45 A.M. Eastern Standard Time,
LISTSERV@GERRY.VANAGON.COM writes:
Still going through head light hell. So here is the senario has high
powered relays, works fine in low beam both sides work, if I turn on the
high beams they both work on the drivers side nothing on the passenger
side,
as in either high beam or driving light. I have redone the grounds and
that
really helped the low beams. All the fuses look good all the bulbs work
as
I have switched the the lights just to test. Not sure where else to
look
high beam switch? Wiring? Any advice would be great.

Kevin, are you sure the fuse for that side is good ? Did you check
the output from the fuse block to the passenger side high beams ? Follow
the current path and you will eventually find the problem. It's not any of
the switches or relays if the other side is working.

Cheers,

Frank Condelli
Almonte, Ontario, Canada
'87 Westy, '90 Carat, '87 Wolfsburg (Forsale) & Lionel Trains
Vanagon/Vanagon Westfalia Service in the Ottawa Valley
Frank Condelli & Associates
Vanagon Stainless Steel Exhaust Systems
BusFusion a VW Camper camping event, Almonte, ON, June 08 ~ 11, 2006