Date: Wed, 4 Jun 2003 13:41:43 -0700
Reply-To: mark drillock <drillock@EARTHLINK.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: mark drillock <drillock@EARTHLINK.NET>
Subject: Re: Lighting Upgrades - Relayed?
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The voltage drop you experience under loads is not solely due to the
rear battery location. VW used a single 6 mm wire from the battery to
the fuse box on all models. On pre 1986 models all of this current goes
through a single .250" spade connector on the back of the fuse box!! I
consider this connection to be a weak point. After 20 years the
connection is not so good and often shows signs of overheating. This is
one reason why I prefer to run a separate new +12 supply wire for the
headlight relays when I install them. (1986 and newer models used a much
larger connector at the fuse box for this single wire carrying the load
for almost the whole electrical system.)
How to connect and run an additional wire depends on the year and model
and whether there is a aux battery setup present. Don't do any of this
if you won't use proper parts and tools to do it right. I prefer to
solder an appropriately sized ring terminal on the end that connects to
the source. Always route carefully, insulate well, and use fuses where
they are needed.
On passenger diesels such as yours I run a #8 wire from the starter
motor stud to an added 2 or 4 fuse panel above the glove box. From here
I split it off for headlight relays and whatever else I want to add.
If there is a battery under the passenger seat I run the #8 wire from
the passenger side battery box to the same 2 or 4 fuse panel I mount
above the glove box.
Don't forget the grounds. I make a new serious ground near my added
relays and run a ground wire from the headlights back to this point.
The pre 86 relay panel connections could likely be cleaned up to improve
things but there is so little slack in the wires that I avoid fooling
with it any more than I have to. Easier if the dash is out. The grounds
for most things come back to 2 circles of male spade lugs above the
fuse/relay panel. Here is where many odd electrical faults and behaviors
are caused. Moisture leaking in from the windshield seal and the radio
antenna cause corrosion in this critical area.
Mark
jon wrote:
>
> With all this talk of "relaying" headlights, I have a couple of questions.
> My 1983 diesel vanagon has a "power shortage" in the front of the van. The
> lights dim when the fan comes on, the stereo freaks out sometimes when the
> head lights are on, etc.
>
> Keep in mind the battery is in the back (engine compartment) on this
> model.
>
> 1) Why relay? Does the light switch not handle enough current? Or, is this
> a relay that controls a seperate power line to the headlights?
> 2) Would install another (or thicker) power wire to the front solve this
> voltage drop problem? (Yeah, I could use the wire resistance tables,
> length, and total current draw to figure out the voltage drop with Ohms
> law...but it's more fun to ask the list
> :-) )
>
> Oh yeah, and I am still looking for a diesel westy. :-)
>
> Jon
