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Headlight relay diagram


Somewhere in the distant past ( about a month ago!) I saw a diagram for making the headlight relay wiring harness.
Now I've seen lots of them but this one was excellent ( Horseplay / Mach1 Driver may have posted it?) and now I understand how all the power goes through the switch I've decided to make a harness.

Can anyone point me in the right direction, I did save the page but after an hour of searching ( I really must sort my bookmarks out) I've given up!

On a good point my new trac loc diff arrives today, assuming it didn't get lost between N.J. and the UK :oops:


Mach1 Driver

Well-Known Member
I've done headlight schematics for the four eye cars (69), but not the others. I suggest that first you talk to Daniel Stern Lighting and find the bulbs and reflectors you want to use. Then once the wattage is known we can plan the circuit around it, or I'm sure that Stern has a relay kit. He will probably suggest manufacturers like Hella, Cibie, and Koito.


The NorCal dude from Belgium
I converted my headlights to H4 bulbs which means they are 55Watts bulbs so the current those bulbs draw is way to much for the exciting headlight switch.

I used all the orignal wiring but plugged in, a selfmade harness with relays , between the connector at the front left front frame ???? and the headlight wiring harness.

In fact it workes like this.

High and low beam wiring/wire connects each to a relay at terminal 86
Terminal 85 of each relay is grounded.
Terminal 30 of both reays goes to the battery , but at the battery you must use/mount a fuse for each relay.
Terminal 87 of those relays goes to each low and high beam circuit.

So Relay 1 is low beam , Terminal 86 is low beam input and terminal 30 is output low beam headlights
And Relay 2 is high beam. Terminal 86 is high beam input and terminal 30 is output high beam headlights

Hope you get this cause my english is very baaaaaaaaaaaad.


The NorCal dude from Belgium
To my knowledge you don't have to add an additional additive with the diff oil to break-in the gears.
But be sure and ask those guys who assembled this diff.
As said before , you may hear a noise comming from the diff the first 100mls.
ps sent you a pm .