Date:         Sat, 18 Nov 1995 11:28:04 -0600 (CST)
Sender:       Vanagon Mailing List <vanagon@vanagon.com>
From:         Dan Beatty <danb@sound.net>
Subject:      Re: headlights on '87

At 10:01 PM 11/17/95 -0600, Mark McCulley wrote:
>The low beams on my recently acquired '87 (rectangular) aren't very
>good--much worse than the Hella H4's I put on my '74 (round). The
>reflectors in the '87's lights look kinda strange to me--there is a tubular
>shaped metal thing surrounding the bulb that is made of a dark-colored
>metal.
>1. Get new headlights from a dealer (maybe they have a better shinier
>reflector or something). I'm dubious of this approach and it probably costs
>more than aux low beams.
>
>2. Install more powerful bulbs. I currently have Sylvania bulbs probably
>55/60W. 80/100W bulbs are available. But what if the reflectors are the
>problem?
>
>
>

An easy test is as follows. 
Conditions: Engine off, ignition key on, headlights on high beam. 
Now for the test: gently lift the dimmer switch until the optical horn
contacts close. How much brighter did the lights get?
Notice I didn't say did they get brighter. It's only a question of how much.
Would you like your high beams to always be that bright? It affect the lows
equally.

It's time for Mr. Voltmeter. VW, and others, feel that they have to protect
us from ourselves, NOT, by wiring the headlamps though the ignition switch.
Those of you that always switch the lights off before turning the ignition
switch off, the correct way <g>, may not have noticed but when the ignition
is off the main headlights don't work. That means the current is being
controlled by the ign switch and in this case without a relay. Given the max
allowable current drop per switch/connection of .2 vdc this is only barely
acceptable when new and perfect. If you connect your voltmeter positive lead
to the battery and the negative lead directly to the headight connector at
the base of the bulb you may be surprised to find a voltage drop of around
>= 2.0 vdc, that's a bunch.

Now what to do about it. Well you can start at the fuse panel and start
tracing the current though the varios switches. Headlight switch, ignition
switch, dimmer switch, various fuses, etc. You must clean, tighten, replace
what ever excends the .2 vdc drop per item. It would better to utilize a
couple of nice heavy, say 30amp with feedback diodes, wired in with nice
heavy wiring to remove the load from the switches, all three of them. They,
the switches, will last a LOT longer, will not reduce current flow, etc. A
good Hella or Bosch relay will have a life cycle under full load of at least
a few hundred thousand cycles. If a little forthought is given to the
installation the relay(s) can be removed and replaced with a premade jumper
if one should fail at an inopportune time.

Now real world. We had that exact problem with Mr. Bus, our 87 Westy with
111k wonderful miles on him. Over 2vdc drop just from the main fuse panel to
the headlamp connector. I cleaned, replaced, traced and mulled it over
before wiring the new relays into him. I used Bosch relays mounted onto
factory relay holders mounted directly onto the top of the original
fuse/relay panel. Using factory connectors and matching colors as closely as
possible it looks "rights". Voltage/current drop is now =< .5vdc from the
battery to the headlamp connectors.

Why are cars/buses wired this way? Well it's cheap, reliable, and meets
certain requirements of the very strict German vehicle code regarding
reliability and failure modes. Did I mention cost saving?

If anyone would want the drawing, and parts list I could e-mail it as an
attachment or snail mail for a SASE.

Have fun, enjoy it now not when you have time someday.


Dan