Getting a wire through the firewall?
- Thread starter philggg
- Start date
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stamp11127
Full Access Members
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
Full Access Members
I’ve been pondering this myself. Let me know what you come up with...
DASAGT
Member
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
Well-Known Member
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
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
Full Access Members
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.
Ooops, just noticed that Stamp already suggested this... sorry about that.
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
Well-Known Member
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
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
Well-Known Member
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
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
I searched around and found this big grommet passing through the firewall. It even has a thick section that you can drill through and have a supported wire. It is on the drivers side firewall. It is easy to access both on the engine side and on in the cabin.
TNFlyboy
New Member
Hey Dennis,
Just got a 2018 Expedition Max Limited last weekend. I am researching Radar detector options. I had a remote unit, Escort Qi45, but it is a bit outdated. What remote unit are you using?
BTW, I just joined this forum and this is my first post. Previous vehicle was 2011 EL King Ranch.
aggiegrad05
Full Access Members
Welcome! Congrats on the new ride.
Dennis48755
Well-Known Member
Hi TNFlyboy,
Yeah, I felt the same way about my Bel-Tronics Vector LR Remote. But no-way could I afford the newer Bel/Escort remotes, so when I bought my 2015 Expedition, I decided to give the Whistler Pro-3600 a try. I was quite pleased with it. When I purchased the 2018 Expedition Limited, Whistler had just announced their Whistler Pro-3700 model so I decided to purchase the new model, and am also very pleased with it. For my 2018, I also purchased the optional Whistler RLC-360 GPS Module which is required for many optional features of the Pro-3600/Pro-3700 (Red Light/Speed Camera database & speed alerts).
Note: my experiences with the Whistlers, has been mostly in rural areas. Since I retired, I haven't been back to the "Metro" (Detroit) area at all and don't miss it. My exposure to higher tech devices (Laser. Red Light/Speed Camera, etc.) has been extremely limited, so I can't speak to how effective detection is for these devices. Typical radar detection and lack of false alerts has been excellent with the two Whistler models.
Dennis
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TNFlyboy
New Member
Dennis, I haven't really looked into the Whistlers. My prior two have been Escorts and they were much better than what I had previous. I really like the remote install and not having a device hanging from windshield. Now that I have a new vehicle I would like to get latest radar detector. I just can't believe the prices of Escorts remote units now. I mean they are virtually taking their windsheild model, splitting it into with a cable and waterproof housings. How can that cost $2500 more?( I know there is more to it than that, but still don't see the huge increase in price being justified).
I live rural too, travel interstate a lot. Try to stay away from the Atlanta city as much as possible.
I live rural too, travel interstate a lot. Try to stay away from the Atlanta city as much as possible.
The best place I found to get accessory power is off of the 12 volt adapter plug on the dash (right next to the center console)(looks like an old cigaret lighter plug).
It is easy to get to the back side of the plug and tap into the power. You have to pop off the bezel round the radio to get to the back of the plug. (actually not that hard with a dash removal tool.. see this video to see how remove the bezel )
It is easy to get to the back side of the plug and tap into the power. You have to pop off the bezel round the radio to get to the back of the plug. (actually not that hard with a dash removal tool.. see this video to see how remove the bezel )
Electrobent
New Member
There are existing grommets with extra nickel-sized nipples on both sides. I ended up using the one on the drivers side. I pushed it through the firewall to the cab side and then cut the cap off the engine side nipple with scissors. This exposes about a 1/4 inch hole. There is another circle on the cab side of the grommet. I shoved scissors through and twisted. The grommet is double sided. Push the wire through while the grommet is still in the cab and then push the grommet back through the hole into the engine bay. Once there you can push it back into place. Battery posts take 10mm wrenches. We will see if my solar charger can keep the battery from sulfating. I tried to use the cigarette plug but it shuts off when the engine is off.
