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MCU2 worth it?

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Only two downsides I am aware of with MCU2 upgrade are loss of FM and satellite radio and if using Light Harmonic aftermarket premium amp, it makes a popping sound on power-up and power-down with MCU2. My S has MCU2 and I have driven MCU1 cars - I would not be as satisfied using MCU1 on a daily basis, but suppose I could get used to it if I had to. I would still be worried about eventual failure of MCU1.
 
Only two downsides I am aware of with MCU2 upgrade are loss of FM and satellite radio and if using Light Harmonic aftermarket premium amp, it makes a popping sound on power-up and power-down with MCU2. My S has MCU2 and I have driven MCU1 cars - I would not be as satisfied using MCU1 on a daily basis, but suppose I could get used to it if I had to. I would still be worried about eventual failure of MCU1.


Is the MCU replacement just the chip or is it integrated with the MCU screen - such that the whole screen is replaced.

Also, & if so are the MCU@ screens less prone to yellowing ?
 
Is the MCU replacement just the chip or is it integrated with the MCU screen - such that the whole screen is replaced.

Also, & if so are the MCU@ screens less prone to yellowing ?

It’s the entire unit plus new IC. MCU2 screens have been prone to getting yellow borders after some time, but not sure if that includes the newest versions. Tesla has a UV cure for the yellow borders and there are DIY solutions discussed on the forum, as well.
 
Just want people's opinions whether MCU2 is worth the $2,500 upgrade.
Given the eMMC issues that are discussed in at least a dozen threads, I have concluded that it may be worth it just to get upgraded hardware that hopefully won’t have the eMMC issue, plus the four year warranty on those new parts. I previously was considering the expensive extended warranty but have concluded that since my battery, motor and new MCU2 will be covered another four years, I will skip the extended warranty and instead watch Netflix on my new screen while also enjoying the silky, smooth navigation screens. On the other hand $2500 ain’t cheap!
 
Just for perspective, people who thought it was worth paying $2,500+tx, still think so a couple of weeks after shelling out the money (maybe a month for the very first retrofits). People who didn't think it's worth it, still think don't think it's worth it. Both groups of course suffer from some confirmation bias, i.e. if you already shelled out the money, you will look for why it was worth it, rather than how you could have had 2 of the latest iPhones instead, while the people who didn't pay for it, marvel at whatever they bought instead (who knows maybe a new iPhone and a iPad to leave in the car to watch netflix or play games at the superchargers), while telling themselves MCU1 is still very usable. :)
 
I don't think the fair comparison is 4 year old MCU1 vs brand-new MCU2

Your choices are:
  • "Factory fresh" (or refurbished?) MCU1 with under-speced memory chip
    • get a 4 year warranty
    • done by dealership so you maybe get a loaner and absolutely get a cup of coffee
    • probably going to fail again in 3-8 years (even without bonkers logging, lots of other things write to flash)
    • no features gained or lost
    • $1800ish (?)
  • It's MCU1+new swissbit memory chip
    • tremendously inconvenient
    • no features gained or lost (ie keep AM/FM/XM and youtube still won't do anything)
    • Probably will last the lifetime of the car
    • reputed to make the MCU operate faster/more reliably
    • warranty probably applies only to the chip, and will be a PITA if you need it
    • $400ish (?)
  • MCU2
    • 4 year warranty
    • you get fancy new features and lose AM/FM/XM radio
    • much faster
    • unknown reliability, likely better than MCU1 but worse than MCU1+swissbit
    • Future proof(ish)
    • $2500
 
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You left out the free option. All of those assume that you NEED to replace your MCU1. Most of them are running fine, and it costs nothing to maintain what you have.

I shelled out around $2500 for a stereo upgrade and I think it was totally worth it. I am fine with my "slow" MCU1. I will consider an upgrade if it fails, but preempting it is not worth the money to me.
 
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You left out the free option. All of those assume that you NEED to replace your MCU1. Most of them are running fine, and it costs nothing to maintain what you have.

I shelled out around $2500 for a stereo upgrade and I think it was totally worth it. I am fine with my "slow" MCU1. I will consider an upgrade if it fails, but preempting it is not worth the money to me.

Yeah, I'm assuming you're evaluating your options when you first get that faint whiff of MCU death.

Unless you've absolutely decided to opt for a new memory chip, you can do the other updates when you're forced to. If you've absolutely decided to never do the upgrade, it makes sense to do the memory chip upgrade whenever / wherever it's convenient to you, not when the chip has died and you need to hire someone from Lithuania with an electron microscope to recover your keys.

I also did not mention that using the MCU2 probably forecloses absolutely rooting your car (I'm not sure how hard it is to root a recently patched MCU1 car, but I imagine it is far easier than an MCU2 car).
 
MCU2
  • 4 year warranty
  • you get fancy new features and lose AM/FM/XM radio
  • much faster
  • unknown reliability, likely better than MCU1 but worse than MCU1+swissbit
  • Future proof(ish)
  • $2500

I recall GreenTheOnly has indicates that the reliability of MCU2 and the eMMC failure is much greater than that of MCU1.

...the EMMC should last somewhere between 100 and 200 years in otherwise ideal conditions....

Source of quote = green on Twitter

This should also be factored in because we know with certainty, that MCU1 will fail within the lifetime of the vehicle.

One other thing to add. We also know that the new cool stuff coming in future updates will only support MCU2. By cool new stuff, I'm going to assume it's under the entertainment category or even stuff where it may be CPU intensive (ie, displaying the cameras on the IC when signaling... Elon said it's difficult, but I would guess that it's also a huge undertaking with MCU1/IC1...

Those that are holding out, I think ultimately they will have to do the 3rd part eMMC replacement, or go for the $2500 Infotainment Upgrade.