Okay, here's a update for those that follow this thread. I am working with two other owners to find a way to restore FM radio after MCU2 upgrade. There's a number of unknowns in this effort. We can't tell you what we don't know, so we are sharing what we know so far. Progress is slow because we are waiting on components, i.e., special cables and connectors to make harnesses to connect the tuner. The connectors are not popularly sold, making the wait longer.
The other two owners that I am referring to are not TMC members. They do not participate. No point right now in using their names. Both are long time owners and frequent posters on Tesla S forum. If you think its already not difficult enough, I live in Hawaii, another lives in California and the third is in Illinois.
The three of us have been watching eBay for more than a month and no sign of a single S/X FM or FM/SM radio tuner. Our best rumor is a new 2018+> FM/HD Tuner (Tuner2) cost about $280 from Tesla. In the meantime, I have purchased a Model 3 FM tuner for less than $100 and we are working to connect it. Same progress issue though. In case you are looking for one, here's the part numbers of what you might want to watch for:
Model S FM/HD 1143703-00-C
Model S FM/HD/XM 1143711-00-C
Model X FM/HD 1143705-00-B
Model X FM/HD/XM 1143716-00-C
Model 3 FM 1079749-00-D
Confirm these part number with Tesla before you buy one, when you can.
Initially, I was exploring installing the M3 Tuner on the passenger side of the car behind the glove box. I found adequate unused space and was going to simply fashion a L bracket to attach it to the car and the M3 Tuner. Mounting-wise the bigger obstacle would be routing FM antenna and the special harness from the left side to the right side behind the MCU /beneath the padded dash. The antenna and new harness would have to have extra length to reach, but getting the wires to the right side is a chore too. Still doable. And if someone used the right side location, positioned the new harness and ran the extra long antenna extension but didn't connect the antenna until the "day before", they might be able to continue to use their MCU1 FM before turning their car in for the MCU2 upgrade.
Today, two of us (both without knowing the other was doing the same thing) removed MCU1 FM/HD Tuner1 from our cars. It was not as difficult as my imagination made me believe it was going to be. I removed the dash end trim, the large left side lower U-shaped trim that goes from the left side of the dash to the MCU. No live wires. To get it out, in total I removed 3 T-20 screws, 3 each 10mm bolts unplugged two connectors. I moved the frame with tuner off the steel tab holding it in place and with a half twist lowered it down down through the hole at the bottom of the dash by holding down the lower black plastic trim panel.
I've mounted the M3 Tuner on the Tuner1 mounting frame and am preparing to put it back in the car. With a special Y type connector, I've also connected the MCU1 FM Tuner1 dual antenna to the M3 FM Tuner single antenna connector. So, vice using the right side, I am going to use the original location of Tuner1.
My MCU2 is installed. There's a new connector on MCU2 that is not on MCU1. Its a BroadR-Reach automotive Ethernet (100Base-T1) (twisted pair)** connector for a digital interface to Tuner2 and that uses Cat5e cable and a unique 4 pin/2 used connector. My problem is, I can't connect it to the back of my MCU now that its already installed. I don't yet know how I am going to get mine connected to my MCU2 once we have made it.
This is not the only issue I have. Smart/knowledgeable owners have told us that there is a Tesla unique procedure that is required to be run when new hardware is added to a car. This procedure is somewhat like a Plug n' Play routine on a computer. Tesla techs run it to change the car's configuration to recognize the new hardware. That process was run when my MCU2 was installed. It will not run again just because I want them to run it. I have no control over running this procedure. Even if I take my S back in and ask them to run the process, there's very little chance they will do it because I asked. Why? Because I have added something to my car that Tesla is not considering adding to my car before/during/after MCU2 was installed. They simply are not interested in helping put FM back on the older Tesla. My chances are slim to get this done. But I am still trying to install the FM tuner. (Its out of sight and secure, so even if this effort fails, it won't hinder operation or devalue my car.)
For those owners considering MCU2: Here's why needs to be considered. I am not saying this is going to work. I am saying there's folks working to try.
If we get it working, if we know it works, here's what you need to consider for yourself.
Assuming you intend to have the MCU2 upgrade installed:
1. Before you turn your car in for the MCU2 Upgrade, install Tuner2.
2. Disconnect Tuner1's antenna, Connect it to Tuner2.
3. Disconnect the 16 pin Tuner1 connector, attach the new harness, connect the new harness to Tuner2
4. Route the new harness over to the general area of the back of the MCU1 so the new BroadR-Reach connector is ready and available to plug into the back of MCU2 when the techs are installing MCU2. (Currently we have no guarantee that the techs will install this new harness connector to MCU2's tuner port. Hopefully after the first few, it will become common.)
When the techs run the unique procedure that allows the Tesla OS to seek out and find the new MCU2 hardware, it will also automatically see Tuner2 and add the FM/HD or FM/HD/XM radio back to the selection choices on the screen.
After we know this works, its going to be important to the entire install to first, decide to do without your MCU1/Tuner1 in order to install/mount Tuner2, connect the old antenna and install/ready the new harness for the techs to plug in - BEFORE you turn your car in to the SC for the MCU2 upgrade.
Tesla owners are smart, talented and generous with their time. Already there's are Youtube videos showing how to disassemble and reassemble the dash. Eventually we will have step by step instructions for how to follow. I am confident with the help of other owners we will have a selection of videos to assist with the parts that people need.
In this effort we are NOT attempting to hack into the Tesla or the Tesla OS. We are not seeking anyone to hack the Tesla. Those preparations we are doing are reversible. And making them operational, we are dependent on Tesla cooperating with the propositioned Tuner2 and plugging the new harness in to the back of the MCU2. We have no influence or means to persuade Tesla to assist us.
The three of us working on this effort are NOT seeking monies from anyone to help with this effort. If you decide to buy a new or used tuner, you do so at your own risk of being able to use it. We are not responsible.
The specs for the material used in this will be shared so you can do it yourself.
The specs for the harness will be shared once we can finalize it. The harness may become available also a reasonable cost of connectors, wire and labor. More later we know more.
** Special thanks for
@kdday (TMC) for help in what's got us this far. He's been a larger provider of guidance and how the process occur.
And here's a few pictures.