Getting a wire through the firewall?

[philggg]

Has anyone found a good way to get a wire through the firewall (behind the dash) without a lot of damage?
Or know a good (fused) place to get some 12 volt power from the engine compartment?

 

[stamp11127]

You might try looking at the firewall on the driver side, up under the dash. In the earlier gens there was a dimple where a master cylinder would go through the firewall. It was plugged by a rubber piece that you can easily pierce with an awl. Depending on the trim level there may be some sound deadening in place.

 

[shane_th_ee]

I’ve been pondering this myself. Let me know what you come up with...

 

[DASAGT]

you can drill; a small hole then after you have everything set seal it with silicone, or you can run the wire around the passenger's door tracing it by the top were the finder and the door meet and pacing the wire under the door seal that is how I did it when I drilled and put in the overhead cab lights on my expedition.

 

[Dennis48755]

I, also, elected to run my wire (to a remote radar detector antenna, behind the grill) around under the door seal. Below the dash up to just below the windshield under the hood.

I looked & looked & looked at the firewall on my 2018 Expedition and came to the conclusion there must be two layers to the firewall. There were dimples on one side and not the other, a bolt stud on the engine side did not have a head on the inside. I just didn't want to deal with it.

If you run the wire(s) under one side of the door seal then follow the door seam a couple inches before coming out of the seal on the other side, you won't have the tight "u" or 180 degree bend in the wire(s) instead you will have two 90 degree turns. I did this on my 2015 Expedition also (same radar detector), and it worked very well with no apparent damage to the wire.

Dennis

 

[Vancouver Bob]

Another option is to find an existing grommet that you can drill and push the wire thru.

Ooops, just noticed that Stamp already suggested this... sorry about that.

 

[Artie]

Has anyone found a good way to get a wire through the firewall (behind the dash) without a lot of damage?
Or know a good (fused) place to get some 12 volt power from the engine compartment?

Did you check the interior fuse box?

I am piggybacking this question as well. I have a dash cam I still need to install and would love yalls thoughts on a good fuse to pull power from.

 

[Dennis48755]

Artie, I spent some time researching this to power my built in radar detector. I was picky, I wanted power that was hot during start/run but not the long on-delay of the power points. It was annoying, when temporarily using a power point, that my radar detector was triggered by the grocery store auto doors and stayed on all the time I was shopping.

I finally came across F46, 7.5 Amp in the Battery Junction Box (BJB). It's for the Family Entertainment System and is hot with accessory delay so it powers off when I exit the truck. I realize it's on the opposite side of the firewall, BUT, it directly feeds C3139 which is under the console. What made it even more perfect for me, is I do not have the Family Entertainment System, so the connector was active but not used (nothing connected to it).

I purchased the Ford Service (Workshop, Wiring & PC/ED) manual on CD so not only did I have the schematics, but the instructions to remove the console. It was surprisingly easy.

Having both the 2015 & 2018 Expedition service manual CD's, I notice something interesting... The 2015 CD contained 358 MB of data, the 2018 557 MB. So the 2018 required 56% more information which shows how advanced it is.

Dennis

 

[Artie]

Artie, I spent some time researching this to power my built in radar detector. I was picky, I wanted power that was hot during start/run but not the long on-delay of the power points. It was annoying, when temporarily using a power point, that my radar detector was triggered by the grocery store auto doors and stayed on all the time I was shopping.

I finally came across F46, 7.5 Amp in the Battery Junction Box (BJB). It's for the Family Entertainment System and is hot with accessory delay so it powers off when I exit the truck. I realize it's on the opposite side of the firewall, BUT, it directly feeds C3139 which is under the console. What made it even more perfect for me, is I do not have the Family Entertainment System, so the connector was active but not used (nothing connected to it).

I purchased the Ford Service (Workshop, Wiring & PC/ED) manual on CD so not only did I have the schematics, but the instructions to remove the console. It was surprisingly easy.

Having both the 2015 & 2018 Expedition service manual CD's, I notice something interesting... The 2015 CD contained 358 MB of data, the 2018 557 MB. So the 2018 required 56% more information which shows how advanced it is.

Dennis

So where did you buy the service manual? And I’m looking in my owners manual but don’t see a fuse ‘c3139’, is there another descriptor for it? Mine is a navi but I’m sure the fuses are all the exact same. I do see in my owners manual there there are several fuses in the cabin fuse box that are listed as ‘not used (spare)’. Do you know if those are just sitting there with no power or is there power to them too? I can PM you this if you think it’s easier... thanks.

 

[Dennis48755]

Helm is the publisher of most Ford manuals.

The fuse is BJB F46 which feeds connector C3139.

I found, by looking at my BCM fuses, that most those marked not used were not present.

Dennis