Hi everyone,
I'm replacing my wiring harness in my '79 with a Painless 12-circuit harness. The problem I'm running into is that the instructions are written for separate gauges, not the printed circuit type like ours. I've traced out all of the wires and what they go to on the printed circuit, but I can't figure out how the gauges gets their power.

Here's what I have:
Blu/Red = Instrument lights
Yel/Blk = Alternator gauge
Red/Org = Alternator gauge
Grn/Wht = Left turn indicator light
Blk = Gauge ground
Org = Fuel sender
Wht/Red = Oil pressure gauge
Red/Yel = Brake warning light
Ppl/Wht = Brake warning light
Pnk = Seatbelt warning light
Grn/Blk = High beam indicator light
Wht/Blu = Right turn indicator light
Red/Wht = Temp gauge
Blk = Light ground

According to the Ford wiring diagram there should also be a Blu/Grn and a Red/Grn wire going to the gauges, but I don't have those. Are the gauges and lights powered by the sending unit wire, or is there separate power coming in somewhere? The Painless harness has wires for the sending units, and a separate power wire that I'm supposed to jumper to each gauge. That doesn't work with the printed circuit. Please don't just send me a copy of the standard Haynes/Chilton wiring diagram, I have those and they aren't helping.

Thanks!

 

There should be a black w/ green stripe resistor wire that is goes into the pc plug on the back of the instrument cluster. This powers the ICVR on the back of the cluster. This powers the instruments. The sending units don't power the gauges, they ground the gauges.
The black wire w/ green stripe will say "resistor wire-do not cut or splice" it should have 8-9 ohms resistance.
This wire will go from the plug on the instrument cluster to a splice behind the cluster where it connects with two other wires, also black/green, one goes to the ignition switch, the other goes to the fuse block. These two wires are regular wires not resistor.

 

You are awesome!

 

Thanks, happy to help.