Firewall access

Vermonster

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Alrighty then: Kings & Queens - where are you punching through for firewall? I need access to the cab to the engine bay? I need to hook up some upfitter switches! :)
 
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Alrighty then: Kings & Queens - where are you punching through for firewall access to the cab to the engine bay? I need to hook up some upfitter switches! :)
To make sure, you know about the factory pass-through wires already, right?
 
To make sure, you know about the factory pass-through wires already, right?
I know about the Upfitter set-up, but I also need to make it trough for my Rigid rear lamps (on the bullet proof diesel 3rd brake light mount).
 
I know about the Upfitter set-up, but I also need to make it trough for my Rigid rear lamps (on the bullet proof diesel 3rd brake light mount).
Sure, but why can’t you use the factory pass-through wires for those lights? Not large enough for the current you’re trying to run? Already have plans for all of the factory pass-through wires and therefore need to run more wires?

To be clear: I’m talking about the 6 (or so?) wires that go from the engine bay, near the upfitter switch fuse block, into the passenger footwell. Blunt cut on both ends, not hooked up to anything on either end. Available for whatever your heart desires as long as you don’t overload them.
 
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Why do you need to bring the wires into the cab? If you just want to use the factory switches to turn on and off some lights, you can just hook up to the upfitter switch wires in the engine bay.

Nevermind, it must be that 3rd brake light setup that drops wires into the cab for power. Pass through wires should be sufficient for that....unless you already used all 4.
 
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I'd pull down the driver's side wheel well liner, along with crawling into the cab under the steering wheel. In the past Ford had a small "pimple" that was in the rubber grommet that surrounded the main wiring harness. I found that cutting a small slit in this "pimple" allowed me to feed thru the firewall within a protected area. Dropping the well liner allowed MUCH better access to the engine bay side to pass the wires thru the firewall.

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Sure, but why can’t you use the factory pass-through wires for those lights? Not large enough for the current you’re trying to run? Already have plans for all of the factory pass-through wires and therefore need to run more wires?

To be clear: I’m talking about the 6 (or so?) wires that go from the engine bay, near the upfitter switch fuse block, into the passenger footwell. Blunt cut on both ends, not hooked up to anything on either end. Available for whatever your heart desires as long as you don’t overload them.
I thought you meant the Upfitter wires themselves. I guess I need go do some research. The Rigid Rock lights use a very small gauge wire - so I think the spare wire you speak of will do!
 
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Sure, but why can’t you use the factory pass-through wires for those lights? Not large enough for the current you’re trying to run? Already have plans for all of the factory pass-through wires and therefore need to run more wires?

To be clear: I’m talking about the 6 (or so?) wires that go from the engine bay, near the upfitter switch fuse block, into the passenger footwell. Blunt cut on both ends, not hooked up to anything on either end. Available for whatever your heart desires as long as you don’t overload them.
I also will need to run some fatty gauge wires for the radio - I think. I need to confirm that.
 
I also will need to run some fatty gauge wires for the radio - I think. I need to confirm that.
I seem to recall that the pass-thru wires are 14ga...
 
I seem to recall that the pass-thru wires are 14ga...
Here is a video which helped me narrow down where things are. Not the best video, but at least it has given me an idea of what is where. I cannot preview on here due to his settings - but you can watch it on YouTube by clicking.

 
2 options we have used for getting cables into the cab from engine bay - round rubber grommet that comes out above your pedals, although beware of breaking the vacuum line manifold with your elbow when reaching in (on a 6.7 - ask me how I know) and option 2 is under the drivers side floor mat. Under your cab, you will see a silver dollar sized rubber grommet, pierce it with a knife or screwdriver, lift up your drivers side sill plate, and gently lift your floorboard up - its in towards the center hump about 3-4” from your sill plate. We have to wire in flasher lights and cell boosters to a plate above our third brake lights, and that’s how we get in/out of the cab. It’s currently -22 outside or I would go take pics for you. If you need more help finding them, I can run out and snap some.
 
2 options we have used for getting cables into the cab from engine bay - round rubber grommet that comes out above your pedals, although beware of breaking the vacuum line manifold with your elbow when reaching in (on a 6.7 - ask me how I know) and option 2 is under the drivers side floor mat. Under your cab, you will see a silver dollar sized rubber grommet, pierce it with a knife or screwdriver, lift up your drivers side sill plate, and gently lift your floorboard up - its in towards the center hump about 3-4” from your sill plate. We have to wire in flasher lights and cell boosters to a plate above our third brake lights, and that’s how we get in/out of the cab. It’s currently -22 outside or I would go take pics for you. If you need more help finding them, I can run out and snap some.
-22? Dang! No worries on photos! I appreciate the information! I will take that under consideration. Stay WARM!
 
OK - I have lost my mind and need to bounce this off someone else who is up on rock light wiring...

The Rigid Rock lights have two wires coming from each one. One Red and one black. I am going to assume the black is neg and the red is hot as they are not marked. I am going to tie both lights into each other by marching colors and then running the two wires from the inside of the truck all the way to the pass through wires to get through the firewall. I can tap the red into the same "hot" 12V power I used for my ARB compressor (there is a power block next to the upfitter wires). Now - the black will need to be grounded to a negative - BUT - how do I get to the upfitter?

Do I need to ground the black and run the "hot" only to the upfitter and not another 12V source?
 
The upfitter is your 12V hot wire - no need to tap into the ARB power wire. Connect to the pass-thru wire, then in the engine bay, connect the other end of the pass-thru to whichever upfitter you want
 
I am adding connectors to my lights, then making a y-harness, then running it to the pass-thru. That way, heaven forbid, if i ever have to take off that mount or anything, you can unplug each light so they will come through and out of the cab without having to cut anything
 
OK - I have lost my mind and need to bounce this off someone else who is up on rock light wiring...

The Rigid Rock lights have two wires coming from each one. One Red and one black. I am going to assume the black is neg and the red is hot as they are not marked. I am going to tie both lights into each other by marching colors and then running the two wires from the inside of the truck all the way to the pass through wires to get through the firewall. I can tap the red into the same "hot" 12V power I used for my ARB compressor (there is a power block next to the upfitter wires). Now - the black will need to be grounded to a negative - BUT - how do I get to the upfitter?

Do I need to ground the black and run the "hot" only to the upfitter and not another 12V source?

Yes only your hot/red needs connected to the upfitter switch, ground/black can go straight to any ground point on your frame
 
The upfitter is your 12V hot wire - no need to tap into the ARB power wire. Connect to the pass-thru wire, then in the engine bay, connect the other end of the pass-thru to whichever upfitter you want
Ok - I second guessed myself with the Upfitters. Then I entered the twilight zone.

I will add these to #2, #3 is ARB. Holding out on #1 for something I may use more often - maybe front lights. I will see if I can find a good ground while I am poking around the back of the cab. I still need to workout how I power gain access to the rear facing dash cam - I may run a USB to the front where I have the other one plugged in. I have an extra port on that mirror adaptor.
 
Each upfitter lead in the engine bay has its own relay and diode and each lead is switched +12v power.

What you mentioned is fine if you want your rigid light to always be hot.

Generally it is not recommend to run multiple 12v accessories off a switched power source because you can quickly get into back feed situations. However it does not sound like you are proposing that.

Also there is no reason to run the ground all the way to the engine bay. Find a good factory ground in the cab. It will keep your engine bay wiring cleaner.
 
Ok - I second guessed myself with the Upfitters. Then I entered the twilight zone.

I will add these to #2, #3 is ARB. Holding out on #1 for something I may use more often - maybe front lights. I will see if I can find a good ground while I am poking around the back of the cab. I still need to workout how I power gain access to the rear facing dash cam - I may run a USB to the front where I have the other one plugged in. I have an extra port on that mirror adaptor.
There’s a lot of hardwire kits and rear view mirror tap kits, pretty easy to do. Mine came with a hardwire kit that just runs down to the passenger fuse box, and has a few fuse taps to power it. My F150 did the same thing and it worked great - very easy to do
 
Find a good factory ground in the cab. It will keep your engine bay wiring cleaner.
Do we know where some of these inside cab grounding points might be located? I’d rather not have to rip up a bunch of stuff hunting for them, but was hopeful, and pretty certain, there were some in there
 

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