Date:         Thu, 4 May 1995 13:45:26 -0400
Sender:       Vanagon Mailing List <vanagon@vanagon.com>
From:         "Chris Chubb" <cchubb@card-u1.card.ida.org>
Subject:      Re: Dimmer relays

/inspection time is coming up soon and i need some help.  i have a '73 loaf
/with no headlight dimmer.  i am perpetually in bright mode.  i checked
/that the wires from the switch [brn and brn/wht] actually go to the relay.
/ i checked that all three wires are connected from the relay to the
/headlights. all are.  i even yanked all the wires out of the fuse box
/gizzmo [all the wires involved that is] and connected them directly to the
/relay.  nothing.  what's up?  if i don't get this fixed, i'm gonna fail
/inspection.  twenty-nine days and counting.

Inside these relay cans are a relay and a diode and a switch.

Does the relay click when you pull the switch? If it clicks, but does
not change, or the other lights go out, the switch is at fault. If
it does not click, the diode or relay is out.

Take the relay out, and use needle-nose pliers to bend back the
tabs that hold the can onto the bottom. Remove the can.

Look for any evidence of burning wires or cracked diodes. Both
have happened to my dimmer relays. Also, they hang upside down
in the busses, right under the windshield, and can fill with
water if you have a leak. If the diode is busted, it is fried. It
will ususlly crack or burn if it breaks. Also look for fried
wires, especially at the coil.

If you see decay or burned parts, replace the relay. Be careful
of newer, replacement units. Many have to opened and a wire
soldered inside to make them work for the older vans.
If your van does not flash the high beams, even if the lights
are off, you will have to modify it. Attach a wire from the
power in to terminal 32. This will allow the unit to toggle.
This is why it is sometimes better to use an older, used
relay.

If the switch is broken, sometimes the little activating foot
needs to be bent back. Push the relay top to watch the action.
Make it toggle the rocker switch back and forth.

I keep swearing that I will replace these units with an epoxy sealed
solid state unit no bigger than a matchbox. But 15 amp capable 
transistors still arent cheap.

Good luck. 

-- 
-- Chris Chubb (cchubb@ida.org) - (703)-845-2287 [Alexandria, VA, USA]
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