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I think I figured out why Model S browser MCU1 will never work

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So here is my story, and someone with more knowledge can correct me if I am wrong, but here goes. I have a 2017 75D w/auto 2.5, FSD, LTE, and MCU1. The browser has NEVER worked. After a reboot it may load one page in like 20 minutes and then never again till reboot. Had multiple techs say it was the websites I went to, the browser just doesn't work on all of the cars, even had the modem chip replaced, and many software updates over the 2 years and still only randomly works 0.0001% of the time. I came to accept that they just won't fix the browser, but then I found out it was all lies or software bugs. How do I know this. Well I took my car in for service and was given an older loaner 85D with no FSD, no autopilot, and only 3G connectivity. I went to the loaner's favorites and it had two of my favorites that don't work in my car. Well guess what? Those two web pages loaded fine and relatively fast even on 3G. Then I tried multiple other web pages and they all worked! No having to reboot the car or any nonsense. So why would an old car with 3G browser work and not a newer car with LTE or on wifi even pull up a single page? It can only be one of two issues:
1)The newer cars just have a broken browser software
or
2)The older cars that are missing FSD, Autopilot, nav traffic, ect. have a much smaller software installed and therefore have enough memory for the browser to actually work.
Do you guys think it is issue 1 or 2 or that my car has a hardware or software defect that needs to be fixed to get the browser to work, because it doesn't work at all, or after a reboot will load one page in about 15 minutes (wifi or LTE good signal) if it loads anything at all.
 
@JimHarris , it might actually be simpler than that. My 2015 MS browser hasn't worked since v9. I recently however replaced my emmc chip in the MCU, and it breathed new life into the MCU - it's now a lot more responsive and yes, the browser has worked since (it's been just over a week, I just checked to make sure, still loads pages include Tesla Waze just fine, even though I hate that I cannot make it half screen as before). The loaner you were driving might just have less wear on the emmc, or more likely its MCU1 failed and was replaced with a new one (which would have a new, unworn emmc chip).

PS> Why change the modem? Were pages loading for you on WiFi but not via modem?
 
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From a very old thread, have you disabled RTTI while trying to browse? Fewer nav/map screen refreshes def improves browser perf. I personally never use the browser so it’s a don’t care for me. If there was true Waze integration then it’d be a diff story!
 
Tesla broke it (more than it was already broken, anyway) a few years ago with an update, so of course it's update related. They did something to make it worse, and since they have a working browser on the newer hardware they never bothered looking at what was broken. Priority is always (1) new cars, and then (2) new cars. If there is time, then they might give some attention to old hardware, but there is never time. Especially when the broken browser is on the hardware that doesn't run on a Model 3 and even new Model S software isn't being quality tested because it's considered old hardware even with the new MCU.
 
This has been discussed before.

(1) The footprint of v10 is much greater than that of the older v8 or v9.
(2) MCU1 is very old, and if you have DashCam and Sentry Mode turned on, it uses a lot of the CPU and memory, so it runs much slower, and the browser barely works.

Try turning off dash cam, sentry mode, RTTI, and you'll see some level of responsiveness from the MCU, and in some cases the browser may work better but still very slow.

I think Tesla had done all of the code optimizations possible with MCU1 (it is 2012 technology). I would recommend (assuming you have $2500 of disposal income) that you consider the Infotainment Upgrade once your vehicle becomes eligible for it. It really makes your Tesla feels amazing with a MCU2 that is responsible, a working browser, sentry viewer, all of the new entertainment features (and yes, the removal of the FM/AM/XM is problematic for some).

The schedule has been update once again and AP2 pushed out to May.

Infotainment Upgrade
 
When I get the car back I will try and turn off real time traffic and dashcam/sentry, though I don't use them and thought sentry is only if you click the icon. But it makes sense since the rental car doesn't have any of those features, it's browser actually works. And no, my emmc chip would not be the cause, even though it is a Dec 2017, I have less than 10,000 miles on it, so no way that memory chip is failing already, and the browser was this bad when it was brand new.
 
When I get the car back I will try and turn off real time traffic and dashcam/sentry, though I don't use them and thought sentry is only if you click the icon. But it makes sense since the rental car doesn't have any of those features, it's browser actually works. And no, my emmc chip would not be the cause, even though it is a Dec 2017, I have less than 10,000 miles on it, so no way that memory chip is failing already, and the browser was this bad when it was brand new.


Can you post a video of the browser in your loaner? Showing how fast it responds?
 
I have found that if my browser gets stuck, it usually takes two (sometimes three) resets to get it functional again. From my personal observations, it seems that the first reset just puts it back to the state it was at before the last sleep cycle. The second one (most of the time) seems to do a deeper reset. This is just I think is happening and have no idea if it's true or not.
 
The real reason is because mcu1 uses QtCarBrowser (an old one from like 2015 or something) and mcu2 uses Chromium as the engine for its web browsers.
And they never bothered to update to Chromium on MCU1 even though they could. It's a priority thing for Tesla, they just don't care to keep cars updates once something newer comes out. It was bound to happen - I just wish they would actually stop updating when they are done, instead of continuing to make updates that only downgrade original performance more and more.
 
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And no, my emmc chip would not be the cause, even though it is a Dec 2017, I have less than 10,000 miles on it, so no way that memory chip is failing already, and the browser was this bad when it was brand new.
Emmc wear is a function of time and mileage, not just mileage. Tesla wrote logs to emmc even when the car is parked with screen off (MCU still runs, manages battery, connects to the Tesla, checks for updates, downloads updates, etc). Emmc starts slowing down however on the day it leaves the factory. Every write wears it down more, as does age combined with temperature exposure. Also, it the emmc fills up (i.e. the less free space it has) the slower it gets. So, your emmc may be actually failing yet, but it's definitely slower than when the car was new.