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Discussion Starter #1
After having my F350 for a few months now, I finally decided to make us of the factory upfitter switches. Using a wiring diagram one of you sent to me (thanks for that, it was invaluable), I decided to add some LED lights to AUX 3, and hook up my roof top strobe to AUX 4.
What I thought was going to be an easy install turning into a job that took several hours and a few skinned knuckles. Don't get me wrong, I think Ford has done an amazing job with the 2011 model, but what were they thinking with leaving the wiring stubs for the AUX switches inside the cab ? Would have been a lot easier if they terminated on the other side of the firewall.
I'm hoping I did something wrong, because trying to fish wires through that rubber gromet that divides the firewall was next to impossible. I fought with that damn thing for over an hour. Didn't help you have to be a circus contorsionist to get on your back and work upsidedown, with the brake pedal in your head, and the emergency brake in the way of your arms. What a frigging nightmare. After fighting with it, I finally ended up just pulling the gromet out and using a awl to punch through it to fish the wire. Then try to get that thing reinserted.
If I was doing it wrong, feel free to coment as I still have to availble AUX switches to use, just don't think I have the energy to tackle it again.
 

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Pulling a wire through the firewall

After having my F350 for a few months now, I finally decided to make us of the factory upfitter switches. Using a wiring diagram one of you sent to me (thanks for that, it was invaluable), I decided to add some LED lights to AUX 3, and hook up my roof top strobe to AUX 4.
What I thought was going to be an easy install turning into a job that took several hours and a few skinned knuckles. Don't get me wrong, I think Ford has done an amazing job with the 2011 model, but what were they thinking with leaving the wiring stubs for the AUX switches inside the cab ? Would have been a lot easier if they terminated on the other side of the firewall.
I'm hoping I did something wrong, because trying to fish wires through that rubber gromet that divides the firewall was next to impossible. I fought with that damn thing for over an hour. Didn't help you have to be a circus contorsionist to get on your back and work upsidedown, with the brake pedal in your head, and the emergency brake in the way of your arms. What a frigging nightmare. After fighting with it, I finally ended up just pulling the gromet out and using a awl to punch through it to fish the wire. Then try to get that thing reinserted.
If I was doing it wrong, feel free to coment as I still have to availble AUX switches to use, just don't think I have the energy to tackle it again.
They invented the 3/4" drill quite a few years ago. Mine didn't even heat it up when I pierced through the Coors can they call a firewall. 1 grommet and I was all set. It is nice if you don't have to drill a hole but you will have a much tougher time trying to get through a wire harness that has a double boot weather proof mucket assembly with a gazillion wires passing through it.
I figure there was much less chance of creating an electrical dilema by locating a dedicated hole on the firewall just behind the fuse block.
 

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That's to bad you had so much trouble. The set up on the 2011 is way better than my 06' was so I pretty happy.

I pulled the rubber gromet out at the start and fished the wires through from under the hood (no need for a drill as there are 'slits' in the rubber) then got all of my connections made to the Aux wires. Slid the gromet along the wires and put it back in from the inside and then hooked the wires up to lights.

I did three switches in less than an hour. I admit it is a little tough on the floor getting up there though but on the 06' the wires were behind where the switches are and it was really tough.

As a side note, I run both Aux 1 and 2 to lights on the front of my truck and due to the switch placement being further away compared to my 06' I ran the power feeds into an old style floor high/low beam switch. That way, the upfitter switches can be on but I turn the lights on or off with the floor switch so no fumbling when another vehicle comes around the corner.
 

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There are 4 wires that are blunt cut that run through the firewall for this purpose. They are taped to the harness above the fusebox on the drivers side under the hood. In the cab they are in that mess of blunt cut wires taped to the harness next to the parking brake.
 

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Discussion Starter #5
The diagram I had only showed the wires inside the cab by the parking brake. I couldn't understand why they didn't have them already blunt cut outside of the firewall - it just didn't make sense. Based on what you are saying though, it seems there are a bundle of wires under the hood. I really wished I had have known that, would have saved a lot of time and effort. plus it makes a lot of sense. Since most lights would be wired outside of the cab, why not have the blunt cut wires readily accessable.

Thanks for letting me know. I'll use that bundle for any other add on's I do.
 

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The diagram I had only showed the wires inside the cab by the parking brake. I couldn't understand why they didn't have them already blunt cut outside of the firewall - it just didn't make sense. Based on what you are saying though, it seems there are a bundle of wires under the hood. I really wished I had have known that, would have saved a lot of time and effort. plus it makes a lot of sense. Since most lights would be wired outside of the cab, why not have the blunt cut wires readily accessable.

Thanks for letting me know. I'll use that bundle for any other add on's I do.
There isn't a bundle under the hood to the best of my knowledge for the upfitter switches.

I just ran my auxillary wires from under the hood, through the rubber grommett, then down to the hole in the fire wall. I still had to contort to connect to the blunt ends of the factory wires so it was a little cumbersome.

I just really liked the pre sliced holes in the rubber grommett because after you push the wires through it would close back around the wire basically sealing it off.
 
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