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I just finished installing an electric headlight kit on my 1978. I am getting ready to hook up the wiring. I am thinking of hooking up the trigger wire ( blue ) to one of the headlight power wires. and then running the Power wire ( red ) and ground ( black ) over to the starter fusible links ( always hot ) and the ground location right near the starter
The horn relay would be a great place on a early C3. However. Not so much on your 78. Your horn relay is not a power connection point under the hood on a 78 like say a 72 would be. Getting a constant hot connection would be best to go right to the starter solenoid. As per switching wire. Best to go to the power wire to the high/ low switch at the base of the steering column.
Oh- careful with the wires- are NOT rated for underhood use-it's only good to 180º and gas /oil resistant
The headlight trigger wire- you will have to diode isolate or run to the dimmer switch-
AND make sure you fuse that wire as well as it is NOT rated for the headlight circuit (20A)
If you just connect the trigger wire to the low beam- they will go down when you switch low to high.
If you connect the trigger wire to the both the low beam and high beam - the lights will not switch between low and high.
If you connect the trigger wire just to the parking lights- when you turn on the hazards- the headlight will open and close...
I checked the rating. And the red wire has 102C printed in it. I also wrapped the wires in tape and used a wire cover tube to help protect it.
Thanks for letting me know about the headlight wiring. I'd hate to have my headlights drop on high beam 😳
Oh- careful with the wires- are NOT rated for underhood use-it's only good to 180º and gas /oil resistant
The headlight trigger wire- you will have to diode isolate or run to the dimmer switch-
AND make sure you fuse that wire as well as it is NOT rated for the headlight circuit (20A)
If you just connect the trigger wire to the low beam- they will go down when you switch low to high.
If you connect the trigger wire to the both the low beam and high beam - the lights will not switch between low and high.
If you connect the trigger wire just to the parking lights- when you turn on the hazards- the headlight will open and close...
Here's one way to do it-
So I'm confused - where exactly is this being wired into?
I have electric and do it the easy way
1) under hood horn relay is always hot 12 volt . It's on the driver side
2) ground is ground so you decide what works best for you
3) blue wire to one of the front running lights and leave the dimmer switch alone
Job is now finished, well that's how I did mine anyhow and I have no problems, but I have never used the flashers
So I'm confused - where exactly is this being wired into?
To the low beam headlight- that way you don't have to run wires all the way inside the cabin to the dimmer switch.
You can buy the male female H4 connectors and make an adapter so no wires are cut.- makes it look nice-clean -professional.
Then the headlights work like they are supposed to-
I’ve seen people hook up the hot to the alternator. What’s peoples opinion on this?
That’s what the instructions in mine tell me to do, but I don’t think I’m going to do it that way since I have an LS engine/alternator. My theory is they want you do it there because it’s the closest power source, but I think I’m just gonna run the power to the fuse box and ground to the frame.
electric headlight wiring question
