Upfitter Switch Help
Posting Guru
Joined: Dec 2006
Posts: 1,391
Likes: 1
From: NorCal
The blunt cut wires for the upfitter switches that are under the dash come from the upfitter relays, if you just tap into the back of the switch then you are bypassing the relays that they are hooked up to.
This means you will have to add your own relays so that you don't burn up the switches!
This means you will have to add your own relays so that you don't burn up the switches!
Token Redneck
Joined: Jun 2007
Posts: 9,339
Likes: 350
From: Breckenridge, TX
holy thread mining....
Are you sure that you're getting the aux wires from the right bundle? There are 4 blunt cut wires that just serve as pass throughs through the firewall into the engine compartment.
Are you sure that you're getting the aux wires from the right bundle? There are 4 blunt cut wires that just serve as pass throughs through the firewall into the engine compartment.
New User
Joined: Sep 2008
Posts: 5
Likes: 0
The blunt cut wires for the upfitter switches that are under the dash come from the upfitter relays, if you just tap into the back of the switch then you are bypassing the relays that they are hooked up to.
This means you will have to add your own relays so that you don't burn up the switches!
This means you will have to add your own relays so that you don't burn up the switches!
thanks
New User
Joined: Sep 2008
Posts: 5
Likes: 0
Yep, I'm positive. I found those too! These wires are in a bundle of about 8. The color codes match what the book says, only they are dead. It appears that it would have been easier to add my own toggle switches and tie them to the key on fuse. I'm concerned about my hooking them up directly behind the switch as posted earlier. They work for now but I'm guessing it's only a matter of time....................
Posting Guru
Joined: Dec 2006
Posts: 1,391
Likes: 1
From: NorCal
Be sure to check fuse #115, it is a 20 amp cartridge type fuse that feeds power to the upfitter switches.
This sounds like it should be your problem since the lights don't even come on on the switches.
And relay #305 also controls all the upfitter switches, so check it too.
This sounds like it should be your problem since the lights don't even come on on the switches.
And relay #305 also controls all the upfitter switches, so check it too.
Cargo Master
Joined: Aug 2003
Posts: 2,241
Likes: 1
From: Here and there
If I'm correct the wires you need to use for the upfitter switches are behind the fuse block. I knwo that where I found them for a strobe install I did on an 04 250.
And here is the how to i did,
Truckblog - How-To Install Hide-a-Way Strobes
And here is the how to i did,
Truckblog - How-To Install Hide-a-Way Strobes
New User
Joined: Sep 2008
Posts: 5
Likes: 0
Upfitter wires update
First thing this a.m. I went back out to my sons truck and re-pulled the fuse box double checking that there was a possibility of more blunt wires lurking around that area. Yup, there they were, sticking out like 4 blunt wires should be. The reason I missed them the first time was that they were attached directly to the back of the fuse box. Geesh, they even had a label on them for the dummies like me to read. Took me about 2 seconds to snip the wires I tapped in to the switches and re-route my new wire directly to the blunt end wires. There were only four as mentioned in the owners manual. All is working just fine now. I'm still questioning what those other blunt wires might be for. They all have the exact same color codes as the four larger wires I just found. I'd like to thank everyone for their input and suggestions. A real big help. Now that I've searched high and low through this site, I read something else about a high speed idle. Should I dare ask if those other wires might be for that??? No, no-way. I know, that would be off topic.
Posting Guru
Joined: Dec 2006
Posts: 1,391
Likes: 1
From: NorCal
It just so happens that one of them is the high idle wire, I just don't remember which one until I get home to check my notes.
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New User
Joined: Sep 2008
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Perfect! I hope the tracer is still visible on those wires since I've poked most of them enough times to cause a elect leak. I'll assume there is already a discussion on the idle speed thing so I'll go and look it up. thanks a bunch. BTW, my sons name is Greg...
Posting Guru
Joined: Dec 2006
Posts: 1,391
Likes: 1
From: NorCal
The high idle wire you want to hook up to is the (BCP) purple w/green stripe.
Here is a thread with good info on the high idle: https://www.ford-trucks.com/forums/4...-switches.html
Here is a thread with good info on the high idle: https://www.ford-trucks.com/forums/4...-switches.html
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