Date: Sat, 2 Mar 2002 02:00:11 +0100
Reply-To: Robert Steven Fish <fish@SALZBURG.CO.AT>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Robert Steven Fish <fish@SALZBURG.CO.AT>
Subject: Re: Relaying Headlights
Content-Type: text/plain; charset="iso-8859-1"
Revisiting the headlight relay scene...
I am going to attempt the infamous headlight circuit rewire this weekend on
my 87 2.1 Vanagon.
Before I go shopping for wire, I wanted to get something straight...
When running your power to the 30 terminals of the relays, where is the best
source for juice.. the alternator or the battery plus terminal??
I just read something which seemed to indicate that the power should come
off the alternator, because then it does not have to pass through any of the
car's internal wiring and will thus not have such a pronounced voltage drop.
But from what I am reading here, it seems that the battery terminal will be
able to deliver the same quality juice as the alternator... is this correct.
I will save a lot of red wire if I go to the battery.
Thanks for the info!
RSF
PS... in addition, it seems that if you take the WHITE wire, directly from
the steering column headlight dimmer switch, to be your relay coil, then you
will end up without a blue dash LED indicating that your brights are on...
or am I missing something here? Looks like that WHITE wire runs through a
fuse and back to the wiring block, to emerge as a white/black wire, on its
way to the 56a at the high beam lamp. Wouldn't it be better to take this
wire for the relay coil??
<º)))>{ <º)))>{ <º)))>{ <º)))>{ <º)))>{ <º)))>{
Robert S. Fish
Salzburg, Austria
1987 Wolfsburg Vanagon 2.1 GL Weekender
1987 Golf Cabriolet
1991 Golf
----- Original Message -----
From: "Alistair Bell" <albell@UVIC.CA>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Tuesday, February 26, 2002 5:37 PM
Subject: Re: Relaying Headlights
Frank,
I am sure you're gonna get a few responses to your battery statement!
When the engine is running and the battery charged, battery voltage is
greater than 12 volts (I read 14.1-14.2 at the battery). The alternator
output is limited to whatever the voltage reg is set at (13.8-14.4) not 12
volts.
If you only read 12 volts across the pos and neg of your battery when the
engine is running then you have alternator and/or battery problems.
The battery must be charged at a voltage higher than 12, the upper limit
being a compromise between charge rate and over charge. Gel cell batteries
have a slightly different charge profile (both equalisation and float).
I get approx 14.0 at the dash voltmeter with no load. The addition of two 8
gauge power lines running up to the front (for aux light and relayed head
lights) makes a big difference in the measured voltage drop when those
aforementioned loads are applied. Used to be (with stock wiring) when I
turned on all the electrical loads the voltmeter would drop below 12V
(wipers, blower, lights, rear defrogger etc), now with the same loads plus a
250W aux light the voltage bottoms out at 12.5)
Alistair
on 26/2/02 3:34 AM, you wrote:
>>
> Never gonna get 13 volts up at the head lamps unless you run 10 guage
> wire to them. Even then I doubt that will work. Battery is 12 volts
that's
> it that's all. Yes, the alternator puts out 13.? volts, but it is
regulated
> to the battery at 12 volts. There is always gonna be some current drop in
> the line which is a factor of the diameter and length of the line. Using
the
> stock wires to the headlamps with the relays bypassing the limiting switch
VW
> put there will get you around 11.5 volts and the lamps. Which is way
better
> than the 9.5 volts there in OEM conditions.
>
> Cheers
>
> Frank Condelli
