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Re: Dim headlight

To: <gregs672liter@netzero.net>
Subject: Re: Dim headlight
From: "John F Sandhoff" <sandhoff@csus.edu>
Date: Mon, 07 Jun 2004 11:15:51 -0700
> ...a '69 1600.

Starting with '69, each headlight receives a constant +12 thru its own
fuse. Hi/lo beams are selected by grounding (thru the headlight
switch and headlight relay) the appropriate filament.

> ...volts drop to 7.60 or so and lamp is dim. If I switch on the high
> beams, the lamp goes even dimmer.

Hi beam draws more current. Any resistance in the circuit causes
a voltage drop; the more current the larger the drop.

Answer: It's your fuse holder.

To prove it, turn on the lights, then open the fuse box, wet the tip of
your finger, and start touching each end of each fuse (no, you won't
get shocked). When you hear the moisture sizzle and you yelp from
burning your finger, you will have found the bad contact :-)

The only reliable solution I've found is to bypass the fuse block. For
now, I use holders that contain an inline fuse and have piugtails that
I connect directly into the wires at the back of the block (I salvaged
a nice block from the JY that I'll swap in 'one of these days'). You
MUST tie into the wires themselves and not the rivet on the fuse block,
as that's where the problem lies: corrosion between the metal pieces
of the fuse block create a bit of resistance. Cleaning the contacts can't
get to the problem spot between the riveted metal pieces.

-- John
     John F Sandhoff   sandhoff@csus.edu   Sacramento, CA

p.s. If BOTH lights are dim, it's usually the ground. But that's another
posting :-)






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