78 front light harness on 73 j

[eskimomann209]

Ok so I kidnapped the front light harness from a wrecking yard 78 and wired it into my 73 junction box
I got the lights to work of course and the running lights work too...
but I can’t seem to read the wiring diagram right to get the blinkers to run... and as a weird side effect I can’t get my rear right brake light to work.... not sure if that related but it worked before my Frankenstein harness idea
Any one know what I’m missing ?
The wires all pretty much matched up color wise I thought but after installing the bulbs today all I managed to do was annoy myself

I checked the grounds they all look good

 

[bucket]

I thought all years of the light harnesses were pinned the same at the firewall junction? The ones I've messed with have been the same, no matter if it's single headlight or dual headlight. But I think the oldest harness I have on hand is '79. Maybe they were pinned different in the earlier years?

 

[eskimomann209]

I thought all years of the light harnesses were pinned the same at the firewall junction? The ones I've messed with have been the same, no matter if it's single headlight or dual headlight. But I think the oldest harness I have on hand is '79. Maybe they were pinned different in the earlier years?

Schematic shows 73-76 then a 77-80 then 81-87

 

[bucket]

I know the 80's harnesses are different than the late 70's harness, but the different functions pin out the same at the firewall.

I don't know what would differ between '76 and '77.

 

[eskimomann209]

This is what I was looking at here.
Looks like the running light portion is fine but the way the grounds shift to make the blinkers alternate is the change.
Lucky me I found a 73 c10 at the local yard. mine being a 73 harness makes this very helpful as well as being lucky enough to find the interior courtesy light circuit complete . And I even found some factory light bezels. ( I had the cheapo repo)
So it was a very productive day and solves my lighting problem in more ways than one !

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[eskimomann209]

Well those are garbage pictures...

 

[eskimomann209]

Got it
Thanks
73 harness from the j yard did the trick
Also it was making the right rear lights not function correctly