As the title states I found some wires bolted to the frame behind the fuse panel, does anyone have any idea if these are factory wires and what they go to? They look o be factory???

 

This type of crimp connector is a commonly used Ford connector for a ground termination

 

Ok so that confirms its most likely factory, but what does it go to? It has a red and black wire on one terminal and a single black on the other terminal...

 

There are some other wires there that you haven't found. A handful of used through the firewall wires. Ford's body builder book explains them.

 

That is cool and all, but what are they going to or coming from? I don't want to cut and splice them as I was going to put a switch on the wires originally but don't want to be cutting something important....

 

Like retiredsparky said, I'd go with factory grounds given the type of bolt that was used and those connectors. That tab and hole in the frame looks like it was to prevent them from turning when they got tightened. Why one would be red gets me though, red's usually reserved for hot, not ground. You could pull them off and see if anything quits working. Why would you want to put a switch on them?

 

I was originally thinking they were the power port wires (as I pulled them and it seemed to stop working for a moment) and was going to put the power port on a switch like I did the one below the cup holders

 

Whoa hang on here. Now we are talking about too many different wires.

The wires that Dan V is talking about are different than the wires Jim is talking about. Jim is talking about grounds, and Dan is talking about blunt cut pass through wires... that pass through the firewall and are blunt cut on the engine side as well.

These wires are not grounded, not powered, and not multiplexed with any signals or reference voltage. They are simply blunt cut wires, to be used for any purpose (within the wire gauge's current carrying capacity) the owner or installer chooses, where a circuit must pass through the firewall.

In the 99-03, these pass through wires are confusingly color coded the same as trailer brake control wires (Red, Black, White, Blue), so once they are located under the dash, it is important to verify that they are indeed pass through wires, and not the trailer brake control wires.

This verification is easily done, since the trailer brake control wiring harness terminates into a brown shell connector that plugs into another connector that is accessible under the dash, whereas the pass through wires disappear off into the sunset of wiring spaghetti that eventually snakes it's way through to the engine side of the firewall.

Looking at Jim's photo, I can see the trailer brake wiring harness already, so we know those aren't the pass through wires. But the pass through wires are typically found in the same general area.

Now, the wires that Jim is talking about are grounds. Jim, have you verified that the red wire is actually CRIMPED to the SAME eyelet WITH the second black wire? In other words, have you actually unbolted those grounds, so that you could visually examine the second black wire eyelet that is hiding behind the first black wire eyelet, to see how the red wire is terminated?

I suspect that the red wire has a smaller non factory eyelet terminal that is sandwiched in between the two OEM black wire eyelet terminals. I suspect the red wire is aftermarket. I recommend removing the bolt holding the wires to verify what you are working with.

 

My next reply would and is, yes I have removed them once, hence my question, I will post a pic of them removed later today when I have time

 

Here is a photo of my stock grounds in that same location which you can compare yours too:







Generally speaking, OEMs will not run more than two ground wires to the same grounding point. In other words, OEMs will not stack more than two eyelet terminals under one grounding screw. Ford distributes bulletins and advisories to vehicle upfitters which detail Ford's best electrical practices, and stacking more than two eyelet terminals under one screw/bolt is one the practices oems caution against.

The axial gap between eyelet washers in your photo was the first indication to me that your grounding arrangement might not be stock... besides the obvious use of the red wire, which is not a typical wire color for ground. There could be more than one reason for the gap. One could be due to another smaller ring terminal between the two stock terminals, but that was merely an assumption. Another reason is due to what follows below:

The second indication that your grounds were fooled with after the fact is due to the way your crimp collars are stacked one on top of the other. That isn't how double stacked factory wires are arranged under a bolt head flange. Factory crimp collars are offset, or fanned away from each other, in order to keep the eyelet washers as flat as possible, in order to promote as great of contact surface as possible, for the least amount of resistance.

I'd be quite surprised to see a red wire crimped WITH your second black wire. I'll believe whatever you describe... but it will be the first time I will have heard of such a thing in the 17 years since these trucks have been sold. I'm always open to learn something new. And I would be just as curious as you to figure out what that is.

 

Your pic is what I see, but one terminal has both a red and black wire dual terminal and a single black terminal (will post a picture here in about 5 or so minutes)

Edit:

 

Since that has the appearance of a factory crimp, the yellow wire and yellow zip tie make me think air bag.

It's a good idea to disconnect batteries before messing with air bag circuits.

There are two things my truck doesn't have, which could potentially explain why my grounds are not like yours:

1. A passenger side airbag, and
2. An on/off switch for the passenger side airbag.

Crew cab trucks never came with an on/off switch for the passenger airbag, and
Chassis cabs did not come standard with a passenger side air bag, not even Lariats like mine.

I would follow the red (pink?) wire to the passenger side air bag deactivation switch, if you have one, or to the passenger side air bag.

 

You could say that I have a rare and nice truck lol

Actually knowing what the wires are going to would be nice

 

I don't see a single red ground wire in any of my wiring diagrams. You may have to follow it if you really want to know where it goes.

EDIT: Are you sure it's red, not pink with a grey tracer?

 

Now that you mention it, the wire does look more pink to me, especially in the new picture that is a lot clearer. Pikachu, what does the PK/GY wire go to?
I'm betting passenger air bag related due to the yellow zip tie, and due to the fact that I don't have the wire (and don't have a passenger airbag or dash switch).