Date:         Tue, 16 Nov 2010 01:22:12 -0500
Reply-To:     David Beierl <dbeierl@ATTGLOBAL.NET>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         David Beierl <dbeierl@ATTGLOBAL.NET>
Subject:      Re: Headlight Upgrade: New Circuit and Switch?
Comments: To: neil n <musomuso@GMAIL.COM>
In-Reply-To:  <AANLkTik05KLsJxBhpe8hFEOVnGa-32CCWyN89mr7dpXN@mail.gmail.c om>
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At 01:12 PM 11/15/2010  -0800, neil n wrote:
>.... my thoughts of a relay-less system are moot. My apologies for not
>reading the diagram closely first.

Neil -- if it's any comfort, back when your '82 was built the average
Japanese car probably had (pulling number out of hat) ten or fifteen
relays in it.  Using relays is normally a sign of a high-quality
setup that's more reliable than one without relays, not less.  When I
turn on the lights in my Corolla and hear that little click it tells
me that Toyota cared enough to do it the right way, just as they
cared enough to weather-seal every single plug around the engine with
greased O-rings.

If your headlight relays were regularly failing then there was
something wrong with the installation.  The type of failure would
point toward the source of the problem.  The likeliest possibility
without any other information would be relays not rated to handle the
current you were putting through them.

If you want to make your system bulletproof, make sure that every
component carries no more than a third of its rated load.  Even for
an ordinary installation, components should carry half their rated
load or less.  Use relays like these:
http://www.tecknowledgey.com/catalog/product_info.php?cPath=57_58&products_id=1885
.They cost ninety bucks each but they're rated for 80 amps DC which
is about three times the thirty or so your big lights will draw; and
you get two in one package.  And so forth.

Yours,
David