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Helping w/ Model S MCU Issues

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Schwachs

International Man of Leisure
Jan 5, 2018
38
13
Arlington, MA
I have a late 2017 Model S that has been plagued with electronics/MCU issues basically since I've owned bought it new in December 2017. Some more constant symptoms include:

- the MCU crashing and needing to reboot (at least a couple of times a week)
- unable to play Spotify or satellite radio (just spinning with a loading screen)
- unable to connect to my car via the app - and can't reconnect until i reboot the MCU
- no sound from the radio unless i reboot
- the voice activation/command doesn't work

Also, restarting the MCU (either from the crash or manually) it can take upwards of four (4) minutes to reboot.

Tesla said that they have replaced the eMMC on it but I'm still having issues... and I'm close to the expiration of my warranty, I'd like to get this repaired once and for all. My S has been in for service likely 10+ plus times for this now and I'm at my wits end. Every time it goes in for repair it seems fine for a few days and then I'm back to square one.

Anyone have any thoughts or suggestions on what to tell the repair people?

Thanks.
 
Probably have a bad mainboard try doing a factory reset. if the reset doesn't clear 100% of everything from your seat settings to Bluetooth and nav history then your mainboard is shot. I had a similar issue after my eMMC was replaced. so i just did the MCU2 upgrade since it was only $1500
 
The only “once and for all” fix for these issues is to upgrade to MCU2.

There’s no other way, no magic fix that your service center is going to come up with on the 11th visit. A brand new never used MCU1 will exhibit basically all of the symptoms you list above.
 
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I really like how responsive and fast my (January 2018) MCU1 Model S performed after the MCU2 upgrade. It doesn't reboot as often anymore, the maps render quickly, voice commands finally work, navigation tells me when to turn before I pass the turn, and the upgraded autopilot hardware lets it see stop signs, traffic lights, etc. on the display. Seemed a good value for the $2000 upgrade I paid.
 
I did the MCU2 upgrade as well - and no regrets. No downside that I've seen so far. I gained all the new entertainment features and it is much more response all around. I also had a stronger overall LTE signal than I did MCU1.
I’m going to Tesla in 2 weeks for the MCU2 upgrade on my ‘17 Model S with 23K miles. Do they also replace the main touch screen and dashboard screen too with the MCU2 upgrade? I also shelled out $10K 2 mo the ago for the 3.0 FSD from the AP 2.5 I had. However, I’m still at the 2020.48.37.6 v10.2 software and I didn’t get the FSD Beta Button. Wonder by upgrading the MCU2 if I’ll get the most current software update and maybe the Beta Button but I’m not holding my breathe.
 
I’m going to Tesla in 2 weeks for the MCU2 upgrade on my ‘17 Model S with 23K miles. Do they also replace the main touch screen and dashboard screen too with the MCU2 upgrade? I also shelled out $10K 2 mo the ago for the 3.0 FSD from the AP 2.5 I had. However, I’m still at the 2020.48.37.6 v10.2 software and I didn’t get the FSD Beta Button. Wonder by upgrading the MCU2 if I’ll get the most current software update and maybe the Beta Button but I’m not holding my breathe.
Yes, all screens are replaced. Yes, getting MCU2 will give you recent firmwares up to and including the FSD beta button.
 
Unless you already have the Full Self Driving package, you'll be losing $2,000 (current pricing for AP 2.0/2.5 cars), or $2500 if you want to keep your FM radio.

But no, no real downsides. Honestly it feels like a brand new car when it's done. No regrets here.
I already have FSD 3.0 on my ‘17 S. When I update to MCU2, will I get the new main and dash screens and will this cost me $1500? Thanks
 
Yes, all screens are replaced. Yes, getting MCU2 will give you recent firmwares up to and including the FSD beta button.
Awesome. Thanks for the quick response and promising news that I’ll potentially be able to opt in to the FSD Beta Button / FSD Beta. I figured I paid Tesla $10,900, I should be included in the BETA program. And now an add’l $1500 for the MCU2 I’m investing. I’m optimist I’ll be happy with all the new upgrades. 😀
 
I’m going to Tesla in 2 weeks for the MCU2 upgrade on my ‘17 Model S with 23K miles. Do they also replace the main touch screen and dashboard screen too with the MCU2 upgrade? I also shelled out $10K 2 mo the ago for the 3.0 FSD from the AP 2.5 I had. However, I’m still at the 2020.48.37.6 v10.2 software and I didn’t get the FSD Beta Button. Wonder by upgrading the MCU2 if I’ll get the most current software update and maybe the Beta Button but I’m not holding my breathe.

I know it has already been answered but replacing the screens (both the main 17 inch screen and the Instrument Cluster) was my main motivation. I had lots of bubble and it was just getting worse. My MCU1 actually was not performing as bad as other stories listed in these forums, but the leaky screens was a an issue that was visually there every time I got in the car.
 
Tesla replaced my failed MCU1 in February of 2020. Recently, my Tesla was in a Service Center and I asked what MCU I had because I have not been able to access the web. They said it is an MCU1. So, back in February of 2020 they replaced my MCU1 with another MCU1. At the time I talked extensively about getting the new MCU2. I was so happy, and all along the mobile serviceman was installing an MCU1. What should I do?