Any update on a Trailer TPMS system?

[Buyer2021]

Finally back to close out my successful 5th-wheel trailer TPMS+rear view cam installation, previous post of my rig and goals is here, then a second post of partial progress here.

Recap of starting point
2022 Lariat (full specs in signature block below) already showing Trailer Tire Pressure menu item on IPC and showing Aux Cam selection on 12" display; 7/4 pin bumper sockets; without all wires to the 12-pin harness stashed behind the bumper.

Recap of goals

• Keep the 7/4-pin bumper sockets for my 8' utility trailer (4-pins) and 17' utility trailer (7-pins with brakes)
• Add a 7/12-pin socket inside the bed for my 5th-wheel RV with TPMS+Rear Cam

Parts used

• Ford Accessory Trailer TPMS+rear view cam kit LC3Z1A189A; this includes 4-wheel trailer TPMS, rear view cam, all needed harnesses, and the 7/12-pin socket for the truck; I did not get the version with Yaw Module because the F150 (unlike SuperDuty) does not support backup-assist for 5th-wheel trailers.
• Ford ML3Z-13A576-TFA wiring harness; this replaced my OE rear harness to get all wires to connector C439 at the rear bumper; the harness had support for 6 proximity sensors, I clipped-off the last on each end because my Lariat only has 4 proximity sensors in the rear bumper.
• Nichols Manufacturing Straight Harness & Mounting Box for 2020-2023 SuperDuty; this harness is a plug-and-play extension from C439 to the back of the 12-pin socket installed in the bedside; custom ordered to 7ft length; it also includes a mounting box for the 7/12-pin socket installed in the bedside; this avoided much tedious splicing of the OE harness and reduced my fabrication work for the bedside socket mounting (I cut-down the flange on the Nichols Box to fit my specific bedside location space). Nichols Manufacturing does great work, their custom-length harness and standard mounting box are beautiful pieces, service was very prompt .
• Curt 56070 7ft 7-pin Tee Extension Harness; this extends the 7-pin harness to the bedside while also leaving the bumper 7-pin socket functional
• Misc: 6mm aluminum rivnuts installed in the bedside for the mounting box; I stole the 6mm black torx bolts holding my 120-VAC outlet to the bedside for mounting the Nichols box (will order replacements from my dealer).

The pics

I'm very happy with how this turned out, it really is nice for my 5th-wheel rig.

Again, huge thanks to the folks contributing info to this thread, especially @GChurch

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[mrtull]

I'm very happy with how this turned out, it really is nice for my 5th-wheel rig.

The work looks amazing. Not F150 related, but where did you put the actual TPMS box that receives the tire valve sensor? Did you run the video wire under the trailer and up the back or over the top and back down the bottom? So glad you got it working.

 

[Buyer2021]

Not F150 related, but where did you put the actual TPMS box that receives the tire valve sensor? Did you run the video wire under the trailer and up the back or over the top and back down the bottom?

All the work to date has been focused on proving-up and completing the 'truck-side' of the system.

TPMS sensors are installed in the trailer wheels of course, but for the test and pics above I just laid-out the 'trailer-side" harness and TPMS receiver on the ground about 4ft offset from the driver's side of the trailer and temporary taped (literally) the cam bracket with cam on the back of the trailer.

I'll be running all of the trailer-side harness inside the trailer, basically following the trailer umbilical cord path, through existing cabinets and cable-runs to the rear overhead cabinet thence to exit through a hole with watertight gland immediately adjacent to the cam over the back window. The TPMS receiver (only ~1.5"W x 3"L x 1"H) will be on the floor between the axles inside an existing kitchen lower cabinet.

The kit harness lengths are generous to allow this (my trailer is only 21 ft overall length) and I've no concern about the receiver picking up good TPMS signals through the molded fiberglass shell of my RV.

 

[Aron]

All the work to date has been focused on proving-up and completing the 'truck-side' of the system.

TPMS sensors are installed in the trailer wheels of course, but for the test and pics above I just laid-out the 'trailer-side" harness and TPMS receiver on the ground about 4ft offset from the driver's side of the trailer and temporary taped (literally) the cam bracket with cam on the back of the trailer.

I'll be running all of the trailer-side harness inside the trailer, basically following the trailer umbilical cord path, through existing cabinets and cable-runs to the rear overhead cabinet thence to exit through a hole with watertight gland immediately adjacent to the cam over the back window. The TPMS receiver (only ~1.5"W x 3"L x 1"H) will be on the floor between the axles inside an existing kitchen lower cabinet.

The kit harness lengths are generous to allow this (my trailer is only 21 ft overall length) and I've no concern about the receiver picking up good TPMS signals through the molded fiberglass shell of my RV.

Wow! So much more ambitious than my setup, where I just ran the camera cable along the outside frame. Nice!

 

[ReturnZero]

I just finished installing the camera kit using the instructions from this thread, including replacing the rear harness and running everything on my trailer, and the camera works great. The only downside is the camera can't be brought up pretty much at all when the vehicle is in forward motion. Does anyone know if it's possible to enable viewing the camera in motion either fullscreen or as the PIP like you can the bed camera, perhaps via coding in FORScan?

 

[Aron]

I just finished installing the camera kit using the instructions from this thread, including replacing the rear harness and running everything on my trailer, and the camera works great. The only downside is the camera can't be brought up pretty much at all when the vehicle is in forward motion. Does anyone know if it's possible to enable viewing the camera in motion either fullscreen or as the PIP like you can the bed camera, perhaps via coding in FORScan?

Mine works in motion (though it takes over the entire center screen, so you can't see nav maps or anything else when it's on).

I didn't change any settings; once everything was plugged in, it just works. If you had to enable something (e.g., via adjusting Forscan settings), you may have to let the vehicle reset by turning it on and off a few times before it finally accepts it.

 

[ReturnZero]

Mine works in motion (though it takes over the entire center screen, so you can't see nav maps or anything else when it's on).

I didn't change any settings; once everything was plugged in, it just works. If you had to enable something (e.g., via adjusting Forscan settings), you may have to let the vehicle reset by turning it on and off a few times before it finally accepts it.

That's interesting, my other cameras work in motion but the little toolbar that comes out giving you camera options doesn't have the Aux button in it, it's a reduced number of options. Maybe I need a software update or something? That's also why I was thinking maybe I could add it to a list in FORScan or something.

 

[Buyer2021]

That's interesting, my other cameras work in motion but the little toolbar that comes out giving you camera options doesn't have the Aux button in it, it's a reduced number of options. Maybe I need a software update or something? That's also why I was thinking maybe I could add it to a list in FORScan or something.

Mine works in motion (though it takes over the entire center screen, so you can't see nav maps or anything else when it's on).

I didn't change any settings; once everything was plugged in, it just works. If you had to enable something (e.g., via adjusting Forscan settings), you may have to let the vehicle reset by turning it on and off a few times before it finally accepts it.

My experience was the same as @Aron - upon installing all of the trailer TPMS + Cam wiring and hardware the software / display all worked flawless in motion.

Having said that my display always had the 'aux cam' button, just showed (and still does) a blue screen without the trailer with its cam plugged in. Hopefully @ReturnZero you're able to 'cure' that with FORScan, please keep us posted and share the details of any successful FORScan mods for adding the aux cam button with in-motion display.

 

[treg00]

@Ford Motor Company, could you look into our options here? I would love to get support for trailer TPMS - I just can’t get anyone to tell me what to buy.

I only am interested in the trailer TPMS too, not any of the other stuff. If you have figured it out, let me know.

 

[mrtull]

Here's a table showing the connector / circuit details

Was under my truck today and the images were profoundly helpful! Question I have for the 12 Pin connector... based on the description above, pin 6 goes to Ground G402. Do you have a location or identifier for what that is?

 

[Buyer2021]

Was under my truck today and the images were profoundly helpful! Question I have for the 12 Pin connector... based on the description above, pin 6 goes to Ground G402. Do you have a location or identifier for what that is?

That ground wire traces to a ground bolt on the outside rear of the driver side frame rail via a branch in the harness between C439 and C423. You should have that ground even if your current 12-pin harness only has the yaw sensor wires, it'll be obvious and you'll have to disconnect it at the ground bolt as you remove that harness to install the fully populated new harness. Just take the replacement harness ground back to the same bolt via the same route as the one you remove.

Even more than visual inspection and pics of the spaghetti-bowl of wire up there, much of this sort of detail becomes obvious as you actually start removing the old to install the new (this ground wire will prevent removal of the old harness until you trace it to the ground bolt and disconnect ).

 

[Iceman2022]

Alright guys, here is my update. IT WORKED!!!!! Honestly did not have a ton of faith this would pan out. I might just be the first one with an OEM working trailer camera in a 2021 model f150! There are some tricks to removing the old wire harness, specifically, you will need someone with small hands/wrists to unplug the backup sensors in the rear bumper and you need to drop the spare tire. Take your time and be really careful when removing the main big plug, one of the other harnesses had a small wire crossing it that you could easily not see and rip out during removal if you don’t disconnect it. All you need is a golf divet repair tool for popping the original wire harness mount plugs and a 10mm socket for removing harness ground from frame. I’m really glad I got under the truck b/c my inverter power cable was actually not mounted properly (lazy factory job) and was dangling dangerously close to my exhaust. Check it out below! Working trailer camera with trailer tpms. Cheers!

for reference I’m using this wire harness ml3z-13a576-tfa and the camera kit LC3Z1A189A https://em.yotpo.com/ss/c/0sDU4qQaf...3/gxZInvIUek0R9LA-yser7_szhVmR4sxZxiJqPXVOqyQ

Alright guys, here is my update. IT WORKED!!!!! Honestly did not have a ton of faith this would pan out. I might just be the first one with an OEM working trailer camera in a 2021 model f150! There are some tricks to removing the old wire harness, specifically, you will need someone with small hands/wrists to unplug the backup sensors in the rear bumper and you need to drop the spare tire. Take your time and be really careful when removing the main big plug, one of the other harnesses had a small wire crossing it that you could easily not see and rip out during removal if you don’t disconnect it. All you need is a golf divet repair tool for popping the original wire harness mount plugs and a 10mm socket for removing harness ground from frame. I’m really glad I got under the truck b/c my inverter power cable was actually not mounted properly (lazy factory job) and was dangling dangerously close to my exhaust. Check it out below! Working trailer camera with trailer tpms. Cheers!

for reference I’m using this wire harness ml3z-13a576-tfa and the camera kit LC3Z1A189A https://em.yotpo.com/ss/c/0sDU4qQaf...3/gxZInvIUek0R9LA-yser7_szhVmR4sxZxiJqPXVOqyQ

This is amazing detective work! I have a '22 XLT 302A with max trailering. It only has the two wires for the yaw sensor. It looks like the harness you replaced included the tail light connectors, correct? With the XLT I have non-led tail lights so that would commit me to an upgrade unless there's another harness for an XLT.

 

[Iceman2022]

The trailer camera kit does have instructions, the wire harness swap is not documented by ford. The local dealership parts guy told me it won’t have any affect on warranty since it’s an oem part and ford hasn’t released guidance. Harness install detailed process below .

1) Drop the spare tire, kit is behind back passenger seat when you pull the top strap and seat back forward
2) work from the connection mount at the spare tire, the connector here is big and fat, and has an immediate right angle for wires. Its a swivel design so you lift the whole top part of it up to get it.
3)slide to your right (if you are looking up with feet under trailer hitch) and look at truck frame by rear left tire, you’ll see a ground wire connecting to main harness connector that is held in place by 10mm bolt.
4) use golf divet repair tool to pry the wire connectors from the frame. You might break some but doesn’t matter. Don’t pull on the wires to remove. There is a little harness that might have a wire crossing your big fat connector preventing you from pulling it out. Follow it and find that it clips in on some sheet metal. To remove you will need to push a tab that is really annoying with something decently long/thin if you have fat fingers like me. I used my phone to snap pic of the top attached below bc it’s impossible to see. Once you do that you can disconnect the crossing wire from adjacent harness. You’ve completed the hardest part.
5) begin removing the old harness now, and work your way to the hitch. Disconnect the old hitch connectors. At this stage I recommend beginning to attach the new harness so you don’t forget how it went.
6) The old harness splits at the bumper, and feeds into lights on both sides of the license plate and backup sensors along the rear bump. 4 total. Start by the license plate lights. These have push connectors on sides you can get with bare hands easy.
7) disconnect backup sensors next to license plate lights. These connectors have a white piece that you have to slide backwards, then push on pretty hard. You’ll feel a “click” when they make it over the tab that sticks out. I used a thin flathead to help.
8) disconnect 2 remaining sensors from the bumper on either end. This is tricky due to the angles and small space, but I got them.
9) remove the old harness push mounts along the inside rear bumper.
10) feed your new harness along the bumper, connect. NOTE, the 250 has an extra sensor on sides of rear bumper so tape the LONG connectors on both ends of the new harness and use the short connector. If you hold up the old harness you’ll see which one to use. I also zip tied extra long sensor wire to make sure it didn’t droop on dual exhaust.
11) go back along everything and make sure all connectors are good and the harness is secure
12) turn on the truck and make sure your license plate lights and backup sensors are working by backing up near a wall.
13) connect trailer and make sure lights etc all working
14) clean your spare tire and put it back
15) enjoy your next haul
I’ll send the trailer camera manual once I’m back at my trailer installing and have it.

@GChurch I ordered the harness and installed it and it worked exactly as you described. Thank you for doing all the research and sharing your findings. Most of us probably would have never figured this out on our own. I did find that the two extra sensors are for trucks with active park assist.

 

[Oakstone]

A '22 with Max Tow should have the right connection for the customer placed camera with TPMS right?

I've got 302A, Max Tow, 360 Cameras, but my Nav and Co-Pilot Assist 2.0 were deleted before delivery. The regular Co-Pilot is there, just not assist.

 

[Buyer2021]

A '22 with Max Tow should have the right connection for the customer placed camera with TPMS right?

"Should"?

Maybe it "should" but my 2022 Job 2 Lariat with Max Tow

• Did not have the 7/12-pin connector on the bumper (had the 7/4-pin connector)
• Did not have the required fully-populated truck-side wiring harness for attachment to that connector (it only had the Yaw Sensor wires in the truck-side harness)

Note that the 7/12-pin bumper connector is included in the TPMS / Cam kit for the trailer (the fully populated truck-side harness is not)

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