tying 70's under dash harness to 91's ignition wiring help

[SteveC]

ok i want to make sure i got this right and maybe just have a little help with all this. I thinned out the 91's under dash harness to just the intrument panel and radio since im gonna use them in the 70 truck w/efi.

I got all kinds of diagrams from both trucks but am still a little confused about the ignition switch wiring(mainly how to tie the two together so that they both get power since im using the new harness fuse panel, and hooking the start wire and acc wire)

the 70's harness
the yellow i believe is hot all the time from the start soilnoid
red with blue stripe is your ignition wire(start)
brown(pink resistor sun damaged) im not sure if i need???
red with green stripe tied into the resisotr wire i dont know if i need to hook up.
black with green stripe i think is accessory or run
purple i have no clue.


91's harness
yellow is hot all the time
red w/green stripe is run
red w/ blue stripe is start to the silinoid
black w pink stripe is on start but is tied into the red with green stripe
black with green stripe goes to fuse panel so just guessing that is accessory or run dunno
grey with yellow stripe i dont know
purple w/ white stripe you can barely see is for rear abs brakes that im sure a 70 doesnt have.




Now do if i got this all correct i can just solder the 91's wires to the 70's wires granted that im sure they will pull the power load with out buring up.

THis should be simple but i think im missing something.

any help would be appreciated and if to help i have to answer some more questions or make something clearer i can do that .

thanks
Stevec

[SteveC]

Guess no one knows Like i said i have lots of wiring diagrams but they can be confusing.

I know for sure what 2 of the wires are.

Yellow is power all the time
red with a blue stripe is start to your start relay

[Dragon]

If I had the late wiring diagram I would draw you a schematic.

[SteveC]

which diagram do you need i can copy the pic and upload it.. The only problem is that on all data i had trouble finding just the ignigtion switch. I can find different diagrams but they are spread out over starting and power distrubition.

just let me know
thank you very much.

*edit
let me know if any of these help

[Thunderfoot]

I can answer some of your questions here... I think...

the 70's harness
the yellow i believe is hot all the time from the start soilnoid Yes
red with blue stripe is your ignition wire(start) Starter wire
brown(pink resistor sun damaged) im not sure if i need??? You will need to use something here (not resistive though) for the ignition on/off wire.
red with green stripe tied into the resisotr wire i dont know if i need to hook up. Interesting... well you could use this for your ignition on/off connection. I wounder where this wire is going
black with green stripe i think is accessory or run This is the power wire to the fuse box, which in turn is power for the fan, radio, instument panel, etc.
purple i have no clue. This should be the "Exciter" wire for the alternator.

[SteveC]

thank you.. i have a extra switch i can hook up and take a volt ohm meter to test out the harness with... i know that there are a few wires that i have to solder back together but sadly this one is better off than the other harness.

Ill go downstairs and check out where that red with a green stripe that is tied into the same plug as the resistor wire. and get back to ya

*edit
the red with the green wire goes into a splice were a red with a yelllow stripe that is cut off comes out of it on one side and on the other side ..
a green with a red stripe comes out along with a solid blue wire (that ends in a connector that looks like it has never been hooked up that blue wires comes out of the harness near where the plug that has the resistor wire and the brown wire that goes to the soilinoid i think joins together)
the green with a red stripe continues through the harness and goes out to the side that goes to the passenger fire wall plugs.

btw this harness has the 71-72 style ignition switch not the 68-70

[Dragon]

Okay from the top:
Old to new
Off the 72 Quick diagram color checked to the harness I have tacked to the wall.
#21 Yellow to Pink/White Hot
#16 Red/Green to Red/LightGreen run signals for everything but the ignition
Run feeds the late model regulator through the charge light.
#32 Red/Blue to Brown/Pink Start
#297 Black/Green to Black/Green accessory.

Purple in your pick is #640 to brake warning light.
The wire large pale looking wire feeds the resistor wire it is pink

[SteveC]

i may be a bit confussed
hmm shouldnt i tie the red with the blue to the red with the blue on both switches?? cause the wire going to the start soilinoid is red w/ a blue stripe.

and the brown/pink is tied with the red w/green stripe on the new one. but is also in the start i guess thinking about it it would tie in together just have to set down and see it i can get this to go all together

also if i tied the brown w/pink to the red w/blue stripe would that cause the starter relay to have power to it at all times since the brown w/pink is tied into the red w/green

thanks for helping me though all this

[Dragon]

i may be a bit confussed
hmm shouldnt i tie the red with the blue to the red with the blue on both switches?? cause the wire going to the start soilinoid is red w/ a blue stripe.

and the brown/pink is tied with the red w/green stripe on the new one. but is also in the start i guess thinking about it it would tie in together just have to set down and see it i can get this to go all together

also if i tied the brown w/pink to the red w/blue stripe would that cause the starter relay to have power to it at all times since the brown w/pink is tied into the red w/green

thanks for helping me though all this

Where they sent the red blue on the 91 is to the clutch interlock or jumper and in one drawing they have it on the starter so go ahead. The diagram does show the Brown Pink must feed power to the other items that needs power during start. No power won't feed backwards since it does not like to take a longer path.

Red Light Green Does everything that the original Red/Green did it runs the truck in the run position.

[SteveC]

ok cool that helps.....though i dont have a clutch jumper any more... just a straight through red and blue wire.

I thined down the harness taking out stuff i didnt need...after tripple checking it wasnt needed of course... though i kept all of it and left enough wire to solder it back in if need be.

thanks for the help... now just to take the time to get the connectors out of the switches.

Though were the red and green on the older switch was smaller gonna have to see if i can just switch connectors on the switches if possible and tie the samller into the larger.

Wow looking back on that i dont know if that even made sense to me....

Thanks again

*edit
I got the connectors out of the switches and am going to have to go to probally radio shack to see if i can get some more of the connectors that went into the old switch... then start putting wires where they need to go

[Dragon]

Funny that I took to electricity like a duck takes to water. Somewhere in the 2000 plus links I have one for those connector pins. If you are in or near a big city go to an electronic supply house. Radio Shack had the larger ones every time I went hunting for replacement pins.

[SteveC]

ok thanks for all your help. We have a radio shack in the mall here ill check them out on monday ... im not all the great with electricity but im getting better, Kinda have to since im going into the automotive repair trade. If i have any more questions i ask in here ok??

[Dragon]

No problem.