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Just picked up a new F450 and I'm installing my trailer back up cam, TPMS and dash cam (the F450 does not have tire pressure sensors and the "ultimate tow package" trailer back up camera is not as Ford led me to believe).
I was looking for a key on power source (found one) and wanted to check out the upfitter switch wires; can't find them. I found a bundle of wires in the passenger kick panel area and another set of 4 wires, but the label and colors do not match the information in owners manual. I read that they may also be in the engine compartment near the upfitter relay box. Do they appear in both places? Where are they in the passenger kick panel as the owners manual says?
You found the pass through wires in the passenger side kick panel. The upfitter wires are under the hood, drivers side tucked down behind the fuse box.
I'm guessing the pass through wires are the group of 4? Where do they appear under the hood? Ford needs to fix the owners manual; it clearly says those six upfitter switch wires are in the passenger side kick panel.
What are the passthrough wires used for? I assumed to hook up external lights I would only need to hook up a wire under the hood by relay box and ground. What are the passthrough wires then?
If you wanted to run power into the truck that is controlled by the upfitter switches, you would connect the upfitter wire under the hood behind the fuse/relay box to one of the passthru wires under the hood. Now one of the wires coming into the truck would be operated by the upfitter switch. The passthru wires are blunt cut on each side of the fire wall and are only used so you don’t have to find a way through the firewall.
I ran front led led light bars in my grille. I cut out the switch and relay that came included with the light bars. I attached the power wire to one of the upfitter switch wires (under the hood, behind the fuse/relay box on the drivers side) and the ground to the ground on the frame. Let’s say if I wanted to run those lightbars in the cab, I would connect the upfitter wire (behind the fuse/relay box under the hood on the drivers side) to the passthru wire under the hood. I would have to add wire to connect the two. I would then connect the interior light bar to the passthru wire on the inside of the cab. That would have my upfitter switch control the light bar inside the cab. I would never run a light bar inside the cab, it’s just an example.
Passthru wires are just an easy easy way through the firewall. No power is supplied.
Upfitter wires are hot wires that that are controlled by the upfitter switches.
The passthrough wires on my 2018 are a pain in the rear to get to and work with. I ended up punching through the rubber seal under the steering wheel. It was a lot easier. Also the passthrough wires are on the passenger side, then you have to run the wires back across the engine compartment to the upfitter wires on the drivers side.
The GN/OR wire appears to the be the “Hot on Start or Run” +12 source for the upfitter switches and relays, but not for their loads. I’d probably use an upfitter switch and relay output circuit instead.
The passthrough wires on my 2018 are a pain in the rear to get to and work with. I ended up punching through the rubber seal under the steering wheel. It was a lot easier. Also the passthrough wires are on the passenger side, then you have to run the wires back across the engine compartment to the upfitter wires on the drivers side.
I did the same. I think having the pass-through wires on the passenger side is just dumb for the reason you state. The pass-through wires need to be on the drivers side. The vast majority of mods are going to be in the drivers area...so you have to run the wire from the dirvers side upfitter to the passengers side under the hood, then from the passengers side back to the drivers side in the cab to run whatever...
I had to run 3 wires into the cab for my lightbar....I punched a hole through the grommet for the main harness under the steering column. That was a PITA, as the grommet is at least 3 layers thick. I'm gonna hole-saw the next one and use my own open grommet...
I know this is a really old thread, but I figured I'd bump this one instead of starting a new one so Upfitter info stays in Upfitter threads.
In my research it seems that the Upfitter pass throughs are on the opposite side of the truck from the Upfitter load outputs (not tremendously well thought out it seems).
Does anyone make an aftermarket "harness" to run cross truck to pick up all of the pass throughs easily?
