More plugs that I have no clue what they do

[FordTruck]

When I did my cab swap thease two plugs where different becuase I used all the old wiring that's on the passenger side under the hood. I forgot witch was with the orignal truck but the cab I put on had one different so I just pluged them in any way they would go. I don't know if they could have something to do with my tail lights and my front turn/marker lights staying on? Any body know what thease do

[fordman]

on the passenger side all the truck have three connectors like that going through the firewall. they are color coded to mate up on the plug itslef i thinnk its red yellow and black. those wires have headlights parking lights starter wires alt wiring all kinds of stuff that go through them. is there something not plugged in? or are you having a specific probelm some place?

[FordTruck]

I had that two prong plugged into the 4 prong plug. The truck starts and runs fine and the head lights work ,but I'm having problems with the tail or turn signals I don't know witch staying on. If I leave the tail light harness plugged in they wouldn't go off and the front lights if I put bulbs in them they will do the same so I didn't know if this plug difference had something to do with it.

[fordman]

ive never seen a two prong on the passenger side. you have two duifferent systems put together. you need to get the orginal stuff from on truck and use just that. or you'll be cutting wires and rerouting all kind of stuff.

[FordTruck]

The old cab was a 70 and so was the new cab. The olny reason I used my passenger side wiring is because the new cab was put on an International frame so all that wiring was spliced up for that motor not a Ford one.

[fordman]

ok so if you resue the ford passenger wiring and cut the other ends of the wires it should be able to tie that to the stuff that is coming off the engine and headlights and other things that are up there. thats all i can thing of to do. when things start getting away from ford i dont know what to do with them.

[Thunderfoot]

You have 2 Different types of wiring styles that ford did in 70… and they aren’t compatible…
1. This 4 prong one you have there with the Yellow wire & Red wire (are for the alt gauge), Brown wire (front marker light), I can’t see the 4th wire… on that “black colored plug", is what the 70 f-350 wiring diagram has. http://www.fordification.com/images/sch ... master.jpg
2. This 2 prong one you have there with the Blue-yellow striped wire (for the horn) and Black-yellow striped wire (main power wire to the cab). This is what the 70 F100 –F250 wiring diagram has. http://www.fordification.com/images/sch ... master.jpg

There are wires in different connectors from each other, so you can’t just plug them in… Ford is really good at color coding the wires and they are about 98-99% the same through the years… You need to check the wire colors on the connectors and be sure they match when connected. You are going to have to move some of them around to match...

If you plugged that 2 wire connector into the 4 wire one and got the Black-yellow stripped wire hooked to that Brown wire, then you have power all the time to the front marker lights. Which in turn (being this is a 70 up truck) will also have power all the time to the rear marker lights! Hence your “tail lights on all the time”

[FordTruck]

Which in turn (being this is a 70 up truck) will also have power all the time to the rear marker lights! Hence your “tail lights on all the time”

I think you just solved my problem It weird to me because the orignal truck I bought was an F100 and the title for the new cab says F100 something must have got changed somewhere along the line What do I need to fix it? Should I go out to the junkyard and try to find a wiring harness that's2 prong and repalce all the wiring in the dash or is there some wires I can cross or switch around and make it work?

[Thunderfoot]

Sorry it was getting late and I left out some more details on the wiring differences… You have one half that is for full gauge instruments with “Amp” gauge (the 4 prong connector), and one half that is for a truck without gauges “has idiot lights” (the 2 prong connector). The F100-250, F350 is just how the wire diagrams are labeled, but there could be some other differences I don’t see right off…

Anyway, I’m not sure which half you have on which side, but if the 4 prong one is on the engine side and you want the Alt gauge to work you will need to find the cab wiring to match… If that's not a concern, then you just have to look at the wires on each plug and find / match the “wire color codes” on each side so that everything is hooked up correctly. You will have to cut and splice wires so they connect up together on the connectors… You'll have the ones for the Alternator gauge left over (Red and Yellow wires) that wont hook up to anything.

Hope this clears it up more.

[fordman]

thats why i never seen a two prong connector up in there. i've only parted out trucks with the guages in them.

[FordTruck]

The cab I bought had the idiot lights so that would be the two prong right. And the 4 prong was off the orignal cab that had gauges. So I just need to find the wire colors and join them together and that should slove my light problems? All the istrument clusters I have are with gauges so would it just be easier for me to go and take the wiring out of the 71 or 72 I can't rember the exact year in the junkyard and put it in my 70 becuase I already have its instrument cluster.

[Thunderfoot]

The cab I bought had the idiot lights so that would be the two prong right

Yes, that is correct.

So I just need to find the wire colors and join them together and that should solve my light problems?

It should and probably a couple of others.

All the instrument clusters I have are with gauges so would it just be easier for me to go and take the wiring out of the 71 or 72 I can't remember the exact year in the junkyard and put it in my 70 because I already have its instrument cluster.

That would make a nicer installation instead of having to cut and splice the wire harness to make it work, and then your alt gauge will be hooked up (not that they work that great). It is all in your preference. One other thing is that the 70 instrument cluster has a different connector on it from the 71-72 so if you got the newer (71-72) cluster to put into your 70 wire harness it wont plug in... so might as well get the wire harness that came with the instrument cluster, full gauge type to match up with the full gauge wire harness under the hood you have.