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12 volt conversion?

2417 Views 3 Replies 2 Participants Last post by  ORCoaster
We just purchased a 66 Beetle that I believe has been converted from a 6 volt system to a 12 volt (everything is currently 12 volt). Under the hood was a wiring nightmare, most of the fuse block was unhooked and the wire ends were just taped together. After replacing the fuse block and fixing the wire issues I only had high beam headlights. After checking the wiring diagram it appears that I am missing a head light relay. Will the 6 volt relay work? Is there a relay for the 12 volt conversion? Thanks for the help.
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You probably wont find an OEM one that does the job. But you don't need one VW specific. Since you are controlling 12 vdc on the headlights you just need to be mindful of the current draw. You can't put a weenie relay in there that can't carry the 110 watts for low or high beams. OH and watts are a measure of power and you find that by multiplying the current (I) by the voltage (E). So to work it backwards to find current you divide the watts by the voltage. ie. 110 watts / 12 vdc = 9 amps Find a relay that can carry 12 vdc and something like 12 or 15 amps. You will be safe, as volts do rise with the alternator charging. Or at least it should bump to 13.5 or better 13.8 vdc

On my 1981 I actually have two different relays, one for the high and one for the low beams. That takes the load off the headlight switch, it is the wire that actuates the power to the relay and power comes from a fused wire from the battery side of the starter. More because of location. No with the battery in the back seat I am not sure where you can grab a convient location for both the headlight wire from the switch and the battery or ignition side. Maybe the best place is the fuse box. It has to have a hot side that is not keyed in some way.

Any automotive store will be able to set you up with a relay, and the plug that has the needed wires dangling off the back. Pretty simple install once you have all the wires sorted out. Which sounds like you have already done.

Shine on!!!!
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Thank you, I didn't think about using 2 relays. Are you able to control the high beams with the dimmer switch?
Yes, I took the wire going to the low and high beams and slipped in a relay that was triggered by those wires. Since the high beam wire is connected to the switch on the steering wheel it works just the same. You wouldn't know they were there except that by doing it that way you get a little better voltage to the lights and thus they are brighter. No more yellow looking lights for me.

Did the same on the caddy as soon as I could. That headlight switch was just a big voltage drop.
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