Help! 1978 K5 tail light color coding?

[J-No]

Searched old threads/but the diagrams did not open up.
New harnesses from LMC.
I'm an idiot.

Thanks in advance

Can you dumb it down for me?
Which colors are which?

Stop/Tail
Yellow
Brown
Black

Backup
Green
Black

Side
Brown
Black

My Guess:
Black=tail
Green=Reverse
Brown=brake
Yellow=Turn

I assume they can all combine except the turn. Harness coming back has 4 colors.

Light green
Dark green
Yellow
Brown

Thoughts?

Thanks again

 

[Capt Ron]

Dark green right turn
Yellow left turn
Light green back up
Brown park lights
Brake light is same circuit as turn.

 

[J-No]

Thx Capt Ron.

The black wires look like they all chain together--and do not go to the harness coming back?

 

[Capt Ron]

Without pics it's hard to say, black wires crimped together is USUALLY ground.

 

[J-No]

That is what it looks like.

Thanks.

 

[J-No]

Something wonky with the dark green (R side clinker and brake). Not working.

Guess I will test the line for power, my connections, and work backwards from there.

 

[Capt Ron]

Your brake circuit goes thru your turn signal switch. Hold down your brakes and wiggle your turn signal switch while having someone watch the right side tail light

 

[J-No]

Thanks. Tried it.

No power to the R rear brake/turn.

L works fine.

R turn signal--on the front it blinks solid. If I manually toggle on/off--it works on the front.

I replaced the turn signal flasher relay. It is pretty loose in the socket--taped it to keep from falling out. Wonder if there is a bad connection in there.

 

[Capt Ron]

If the front is working the flasher is good. The front does not interact with your brake light switch. It is hard to get to but on the bottom of your steering column there is a flat electric plug with about 7 wires coming out, check the dark green wire there. I prefer to work front to back on this type of problem.

 

[Capt Ron]

on the front it blinks solid

Blinks solid??

 

[J-No]

sorry, lights up solid.