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Installing a Yaesu FTM400 Ham Radio in my 2023 Model X

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Just as when I installed my FTM-400 in my 2017 Model X, I faced a whole new set of challenges when it came to reinstalling the radio in my new 2023 MX.
  1. I researched the issues first and was advised that the newer models (including mine) had a "16V" bus. I tested the cigarette lighter (CL) outlet and discovered it delivered 15.1VDC.
  2. I had used the Trailer Brake outlet under the driver-side carpet (US models) so I plugged my custom cable used to power my radio into this socket. It was supposed to supply higher current )20A) than the CL (12-14A) outlet and I didn't want to use that outlet unnecessarily so I could use it for other accessories. That socket also supplied 15.1VDC.
  3. Suggestions from fellow ham radio operators included installing a Buck converter or several diodes in series. Each diode would drop the voltage by .6 to 1.0 VDC so two or three should get the voltage closer to a tolerable 13.5 VDC. I tried Schottky diodes I had on hand but they only dropped the voltage by .1VDC each.
  4. I ended up removing both of the console side panels to see if I could install the radio into the rather cavernous forward console. While the radio fit (nicely), I could not find a suitable opening in the back where the power and antenna wires could be routed. I was also concerned with heat and being able to hear the speaker. I chose to mount the radio to the hard-plastic wall at the passenger's feet but up off the floor so the passenger would not kick it. In the FTM400, the speaker is on the radio but that does not seem to be an issue. The new Yaesu FTM500 has a speaker in the control head so I expect to upgrade to that model if it arrives before I'm finished installing the 400. Note that I need access to the radio to connect the programming cable and the memory card.
  5. Next, mounted the antenna in the only suitable place on my MX. Since the gull-wing doors come so close to the open rear hatch lid, that option was out. I ultimately used the frunk lid on my 2017. I watched a video (Installing a front camera) that had a hint on how to route the thin antenna cable from my trunk-lip mount (Diamond K400SNMO). This required that I removed three rubber/plastic covers from inside the frunk to expose the seam between the outer skin and the body. Once you remove the two panels from just inside the passenger door, and peel back 18" or so of the weatherstripping, you'll be able to run a fish wire through the seam and pull the tiny cable through. (Sure, remove the PL259 adapter first). Thread the wire behind the panels and reinstall the panels--they all snap in place. I have a set of plastic tools used to remove these panels without damaging them. I had just enough antenna cable to reach the targeted installation point.
  6. Note: I chose NOT to install the antenna on the driver's side as there are several large (I expect high-voltage/current) cables on that side.
  7. In the 2017 MX, I bought a ProClip control head mount that clipped to the AC duct to the right of the steering column. I had to modify it to move the radio about an inch further away from the main screen. Once modified, it worked perfectly and when I removed it before selling, there were no marks at all on the vent. For the 2023 MX, I found that ProClip had a new version intended to mount to the left of the yoke (it only works for MX models with a yoke.) I have yet to get to that part so I'll update this post when I get it installed. I intend to route the flat control cable under the panels back to the radio. I would be willing to part with this customized 2017 MX ProClip mount.
  8. I do not have a dedicated microphone clip which I'm hesitant to install (personal preference).
  9. I leave the USB programming cable connected to the radio and stored in the console as I'm constantly reprogramming it for my volunteer events. Getting to the memory card is too hard on my old, stiff back.
The only question I have is what happens when something on the DC bus shorts out or draws too much current? I heard that Teslas don't have fuzes but use special current monitoring sensors instead and automatically shut down circuits that are misbehaving. How does one reset this circuit? Restart the car?

The only question I have is what happens when something on the DC bus shorts out or draws too much current? I heard that Teslas don't have fuzes but use special current monitoring sensors instead and automatically shut down circuits that are misbehaving. How does one reset this circuit? Restart the car?


Below from: Questions about lack of fuses on Model 3
Some info here:
Ingineerix[S] 3 points 3 months ago

They use "virtual fusing". So one of the body controllers monitors the power being consumed by the phone charger, and when it exceeds the limit for that particular circuit, it cuts power do it. Sort of like a virtual circuit breaker, but without any moving parts. Then when the fault is cleared (you unplug the faulty charger), the system restores power to the circuit. This also allows the car to tell you "Overload in Cigarette lighter port, power interrupted", this way you know something is wrong and can take action. This was done for fault tolerance, but it makes the car safer and more reliable.
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Thanks. That makes sense.
Update: I'm still fighting off COVID and can only do a few hours of work on this at a time.
Once I routed the power cable from the trailer brake outlet, I tested the power and I got 15.1VDC as expected. The harness was too long so I cut it (one conductor at a time) and soldered on a new connector. Just to be safe, I retested the power. Nada. Something had tripped the breaker. I rested for 15 minutes or so and retested. It had returned. SMH. Having no choice but to proceed, I mounted the control head using the ProClip bracket. It was dramatically easier to install than the 2017 version. Routing the control head cable was a PIA until I used the power harness cable as a fish tape. Tip: Don't put back the console side panels until you are completely done. I'm now a lot more comfortable attaching the radio to the side panel--well above the passenger's feet.
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Reactions: scottf200
It's in. Wow, what a job.
Congrats on the install!

I also have a FTM400 in my 2022 M3. I mounted my rig in the center console. The head is mounted in a tray on top, and the base is hidden underneath.

The speaker on the base unit is only OK - a little hard to hear clearly when driving on the highway.

I also found the hood on the M3 was not connected very well to the rest of the chassis (it was only making contact through the hinges) which was causing some reception issues. I installed a ground strap between the hood and the body. The doors and trunk seem to have solid factory ground wire connections.

What antenna are you running on that NMO lip mount?

Here are a few pictures of my radio.



I'm using the Larsen 70/2M NMO. I might try adding a ground strap but the surface area of the frunk seems enough for a good counterpoise. I like the in-view approach of the ProClip as it does not mean I have to take my eyes off the road (as much) as an out-of-view approach. The new FTM-500 has a built-in speaker so that should help hear the radio. My MX also is far quieter than my 2017 MX so road noise does not seem to be as much of a problem.
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@Beta V Hi, did you finish your installation? I'm currently using ID-52 on my 2017 MX, but upgrading to 2023 MX later this year. I'm also thinking of changing from handy radio to a mobile rig, but these days, mobile rig choices are limited.
I'm very interested in your passenger seat installation and the ProClip head-unit installation.

My antenna (Diamond NR950M) setup:
Yes, it's been up since Mid-March. There are FTM-400s around as people transition to the FTM-500 that's just being released to retailers in limited numbers. Be sure to rig a circuit to lower the voltage from 15.1 to below 14. I used three silicon diodes in series to do just that. I mounted the radio high on the wall of the center console on the passenger side. There is nothing behind that partition but use shorter screws. The Control Head cable and power wires (from the trailer brake connector) are routed under the dash to the radio.