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Upgraded MCU1 to MCU2 - Are you experiencing New Problems?

hybridbear

Member
Oct 6, 2015
750
300
Minneapolis
I am embarrassed to say I just noticed a problem with my MCU2 upgrade. Tesla doubled my odometer read... Luckily for me I have TeslaFi and can pinpoint the exact time it happened. Now to fight with them to roll back my mileage.
Did Tesla get this fixed for you? Any word on how it got messed up?
 

hybridbear

Member
Oct 6, 2015
750
300
Minneapolis
We have had a negative experience so far with MCU2. We had it installed about 10 days ago. Within a couple days of install we started noticing strange screen behavior. The screen detects phantom touches. The phantom touches seem to be limited to the bottom edge of the screen. While we are driving the car will randomly turn the HVAC on & will also lower the temperature. It will also randomly turn down the radio volume. This will happen multiple times per minute at times, sometimes multiple times within 10-15 seconds, and then won't happen for 10-20 minutes.

In addition to those issues, the screen has also completely frozen a few times. When it freezes even the double scroll wheel reboot often doesn't get it back. It has taken 4-5 reboots to get the screen to unfreeze. Tesla's theory is that the screen is getting overwhelmed with touch signals that it freezes. We have an appointment for this Thursday but Tesla has said they don't know if they will be able to get parts by then to do anything for us...

Here is a video of the frozen screen:
And this video shows the HVAC turning itself on & then turning down the temperature:
 
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markn455

Member
Apr 8, 2016
372
150
Ball Ground, GA
The only issue I have experienced with the MCU2 is the cellular connection gets stuck in 3G and will not switch to LTE unless I reboot. I know exactly how to duplicate this issue, Tesla knows about it and claims it is a firmware bug. A fix is coming, but this is 4-month-old information and it has not been fixed.
 

hybridbear

Member
Oct 6, 2015
750
300
Minneapolis
The only issue I have experienced with the MCU2 is the cellular connection gets stuck in 3G and will not switch to LTE unless I reboot. I know exactly how to duplicate this issue, Tesla knows about it and claims it is a firmware bug. A fix is coming, but this is 4-month-old information and it has not been fixed.
Is this an issue for every car with MCU2? Or just cars that went from MCU1 to MCU2?
 

MattMatt

Member
Aug 12, 2016
75
211
Los Angeles, CA, USA
Did Tesla get this fixed for you? Any word on how it got messed up?
Tesla did fix it. Basically the MCU seems to be the store of the odometer data, so when they install a new one they're supposed to key in the odometer of the old one, and they mistyped mine and added 35,000 extra miles or so. They reset the odometer back to the right value, but there have been a few negative side effects:

1.) In the tesla system it shows my warranty as expired based on mileage since it went beyond the first warranty value, they said they would fix it, but basically I think they're hoping I don't come in again for a warranty item and I'll have to fight with them if I do.
2.) The Current trip value will not zero out, any time I reset it, it goes to 32k miles on the current trip. I don't really use it for anything, and TeslaFi tracks my mileage just fine for me, so I haven't bothered to get it fixed...
 

jak

Member
Apr 20, 2013
51
27
California
I had my 2015 Model S AP1 car upgraded to MCU2 a little over 2 weeks ago and the UI performance improvements from 1 to 2 are amazing! I did not opt-in for the $500 FM option as I never use it. Was listening to ABC News until that died a slow death into nothingness due to ABC licensing issues with LiveXLive. I did notice some other minor issues with the MCU1->2 upgrade:
  • The auto-volume drop when opening a door no longer works. The volume stays the same when a door is opened. It used to drop when a door was open and increase back when it was closed. I went thru all the menus to see if there was a setting to adjust this, but nope. I'm guessing it can only be changed when in factory mode, so I'll have to ask a tech if I ever need to take it back in for service. Nevermind! After opening the door and lowering the volume, then closing the door and increasing the volume, it seems to be behaving now.
  • The audio bass response has increased. The bass is really noticeable when I'm not driving, and I addressed it by lowering the bass freq to the lowest setting. The bass is less noticeable due to road noise when driving. However, I did change out the stock amp and speakers/sub a while back which did increase bass response, so maybe the new MCU2 has a preamp that pushes out more bass? Either way, minor and easily-addressed issue. I'm sure the day I sell the car, the new owner will enjoy the improved bass! ;)
 
Last edited:

Gogreen

New Member
Jun 5, 2021
1
0
Denver
Yes I just had my 2015 p85D L upgraded from the failed MCU1 to the MCU2. I already upgraded several years ago to LTE but didn’t receive a credit for that and the whole upgrade cost $1,500.00. Now I’m experiencing poor cellular connectivity. I cannot connect to my car through the app at my home as I was able to using the previous MCU1. I’ve had the LTE prior to the MCU 2 upgrade, and now it must be a poor connection like others have described as well as the MCU2 upgrade issues.
 

Michael Sinz

Member
Jan 20, 2018
10
7
Duvall, Washington, USA
The only problems I am running into with MCU2 vs MCU1 are:
1) Sentry mode does not save to the flash drive on MCU2 but did on MCU1. Normal dash cam does work, including save on honk.
2) USB Music does not always work when I get into the car. Sometimes it starts right away, other times it can take minutes before starting.
 

WhiteWi

Supporting Member
Supporting Member
Feb 21, 2021
591
455
Somewhere in Universe
MCU2 upgrade has been great (except for no AM radio, the stations I listen to aren't available on TuneIn, and neither iHeartRadio nor Radio.com are supported, so I use the ProClipUSA air vent mount when I want to listen to those stations). My MCU2 has crashed a small handful of times while driving, resulting in pitch black interior on both screens for a few minutes. Turn signals continued to work, although the "clicking" noise was off.
Happened to me last weekend when driving in the middle of the road trip. I thought my car bricked. Stopped and waited until it came back on.
 

AustinP

Active Member
Apr 6, 2015
1,312
1,053
Belgium
I've had the MCU2 upgrade for a few days, and I have a few concerns to share.

- Wifi: The MCU2 is not able to find any of the Wifi broadcasting. I manually setup one, and that worked. I immediately contacted the SeC, who started troubleshooting last friday. No reply so far, I'll contact them again, as the situation has not improved
- LTE: The MCU2 easily don't find LTE or 3G. Almost every time I get in the car, it will not find LTE immediately. After about a minute it connects. This never happened before, MCU1 was always directly connected. This is also bothersome as the car, when parked away from home, so without Wifi, is not reachable and cannot use remote climate & so on
- Text Messaging: In MCU1, I could easily send text message. Slow, but worked. With MCU2, it tells me I need iOS13 or Android 9. I indeed have iOS14, and it worked fine with MCU1.

If you recognise any of the above, let me know, in case this is "normal". Thanks
 

WhiteWi

Supporting Member
Supporting Member
Feb 21, 2021
591
455
Somewhere in Universe
I've had the MCU2 upgrade for a few days, and I have a few concerns to share.

- Wifi: The MCU2 is not able to find any of the Wifi broadcasting. I manually setup one, and that worked. I immediately contacted the SeC, who started troubleshooting last friday. No reply so far, I'll contact them again, as the situation has not improved
- LTE: The MCU2 easily don't find LTE or 3G. Almost every time I get in the car, it will not find LTE immediately. After about a minute it connects. This never happened before, MCU1 was always directly connected. This is also bothersome as the car, when parked away from home, so without Wifi, is not reachable and cannot use remote climate & so on
- Text Messaging: In MCU1, I could easily send text message. Slow, but worked. With MCU2, it tells me I need iOS13 or Android 9. I indeed have iOS14, and it worked fine with MCU1.

If you recognise any of the above, let me know, in case this is "normal". Thanks
Definitely not normal.
 

cousin_IT

Face provided by boredhumans.com
Oct 27, 2020
357
276
Netherlands
I shared my experiences in the Dutch thread earlier but given the many mentions here on LTE problems I figured my story could be useful to some.

I upgraded to MCU2 as I had an MCU1 w/ 3G connectivity and 3G will be phased out at the end of 2021 in The Netherlands. After the retrofit I had intermittent connectivity problems: On longer drives (> 45 minutes) LTE would drop for 2 minutes and the connection would re-establish as 3G for the remainder of the drive. Stopping and restarting would get back LTE. Sometimes I would have 3G for the entire drive. After sharing the data points with Tesla they wanted to recheck the car in the SC. Their findings:
  • The car still had a so-called SIM extender that was originally fitted in 2015. It had 2 problems:
    • It was not able to support the LTE connection
    • It was originally set to France instead of The Netherlands and was therefore always roaming. To lower roaming costs for Tesla it would switch back to 3G intentionally
  • Installing a new e-SIM (wiki) solved these problems
Some points to consider:
  • Since my car was delivered in October 2015 I expected it would have LTE connectivity but I never saw it onscreen. With what I know now I might have gotten LTE if I were to drive to France
  • The SIM extender technology (which is in fact a hardware box) is outdated and MCU2 supports e-SIM. When I got a quote for MCU2 it also showed the e-SIM but when I received the invoice it no longer mentioned it but referred to the SIM extender
  • To me it's unclear if the SIM Extender is really supported with MCU2 or if local SC's want to save themselves some time by not swapping it for an e-SIM
Take-away: If you're facing LTE connectivity issues after an MCU 2 retrofit check your invoice to see if they kept the SIM extender or if they swapped it for an e-SIM. The SIM extender might be causing the problems.

If your MCU 2 invoice doesn't mention either of these this probably doesn't apply to your region
 
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AustinP

Active Member
Apr 6, 2015
1,312
1,053
Belgium
I shared my experiences in the Dutch thread earlier but given the many mentions here on LTE problems I figured my story could be useful to some.

I upgraded to MCU2 as I had an MCU1 w/ 3G connectivity and 3G will be phased out at the end of 2021 in The Netherlands. After the retrofit I had intermittent connectivity problems: On longer drives (> 45 minutes) LTE would drop for 2 minutes and the connection would re-establish as 3G for the remainder of the drive. Stopping and restarting would get back LTE. Sometimes I would have 3G for the entire drive. After sharing the data points with Tesla they wanted to recheck the car in the SC. Their findings:
  • The car still had a so-called SIM extender that was originally fitted in 2015. It had 2 problems:
    • It was not able to support the LTE connection
    • It was originally set to France instead of The Netherlands and was therefore always roaming. To lower roaming costs for Tesla it would switch back to 3G intentionally
  • Installing a new e-SIM (wiki) solved these problems
Some points to consider:
  • Since my car was delivered in October 2015 I expected it would have LTE connectivity but I never saw it onscreen. With what I know now I might have gotten LTE if I were to drive to France
  • The SIM extender technology (which is in fact a hardware box) is outdated and MCU2 supports e-SIM. When I got a quote for MCU2 it also showed the e-SIM but when I received the invoice it no longer mentioned it but referred to the SIM extender
  • To me it's unclear if the SIM Extender is really supported with MCU2 or if local SC's want to save themselves some time by not swapping it for an e-SIM
Take-away: If you're facing LTE connectivity issues after an MCU 2 retrofit check your invoice to see if they kept the SIM extender or if they swapped it for an e-SIM. The SIM extender might be causing the problems.

If your MCU 2 invoice doesn't mention either of these this probably doesn't apply to your region
This is interesting feedback, thanks.

1624892386717.png


I have above on my invoice. It does mention "Without SIM Extender", but does not make much sense to me. Does it to you?

I found this URL, that help sees which is the mobile network: https://www.hashemanian.com/whoami

1624892507260.png


So in my case, I can see I have KPN from The Netherlands SIM.
 

cousin_IT

Face provided by boredhumans.com
Oct 27, 2020
357
276
Netherlands
This is interesting feedback, thanks.

View attachment 678777

I have above on my invoice. It does mention "Without SIM Extender", but does not make much sense to me. Does it to you?

I found this URL, that help sees which is the mobile network: https://www.hashemanian.com/whoami

View attachment 678778

So in my case, I can see I have KPN from The Netherlands SIM.
You probably had a SIM card installed instead of a SIM extender and they moved that card to the new unit (which I believe can also hold a physical SIM). If you have connectivity problems you can ask them if they can check if the installed SIM is LTE capable, older SIM cards sometimes are not compatible.
 

AustinP

Active Member
Apr 6, 2015
1,312
1,053
Belgium
I've had the MCU2 upgrade for a few days, and I have a few concerns to share.

- Wifi: The MCU2 is not able to find any of the Wifi broadcasting. I manually setup one, and that worked. I immediately contacted the SeC, who started troubleshooting last friday. No reply so far, I'll contact them again, as the situation has not improved
- LTE: The MCU2 easily don't find LTE or 3G. Almost every time I get in the car, it will not find LTE immediately. After about a minute it connects. This never happened before, MCU1 was always directly connected. This is also bothersome as the car, when parked away from home, so without Wifi, is not reachable and cannot use remote climate & so on
- Text Messaging: In MCU1, I could easily send text message. Slow, but worked. With MCU2, it tells me I need iOS13 or Android 9. I indeed have iOS14, and it worked fine with MCU1.

If you recognise any of the above, let me know, in case this is "normal". Thanks
So a followup to my previous post.

Ranger came by today for my Text Messaging issue (#3 in previous post).
He is driving an original P85D, modified as a service car. He had the MCU2 upgrade.

His visit answered both issue #2 & #3

1) Text Messaging: He could replicate the issue with his phone in his car. Ergo, this is not just my car. He did not find anything similar in their KB, hence he created a new case. So this is now the waiting game for the next update with "minor fixes"

2) LTE: As he was trying voice, he did not have coverage. He immediately told me that it's like that for any MCU2, whether "original builtin" as for all S/X since April 2018, or for upgrade like mine and his.
I'm quite surprised here. Owner of S/X with MCU2 just accept this? It would mean 3 years and not enough complain, so this is not being fixed? Feels like this one will never be fixed, and it's crazy.

So to whomever recognise this: "The MCU2 easily don't find LTE or 3G. Almost every time I get in the car, it will not find LTE immediately. After about a minute it connects.", please complain to your SeC. The more attention it get, the more traction it will have.

One thing I saw over the years, is that Tesla is listening, but we have to be loud enough to have the issue pulled out of the back log and into the next sprint.
 

hybridbear

Member
Oct 6, 2015
750
300
Minneapolis
So a followup to my previous post.

Ranger came by today for my Text Messaging issue (#3 in previous post).
He is driving an original P85D, modified as a service car. He had the MCU2 upgrade.

His visit answered both issue #2 & #3

1) Text Messaging: He could replicate the issue with his phone in his car. Ergo, this is not just my car. He did not find anything similar in their KB, hence he created a new case. So this is now the waiting game for the next update with "minor fixes"

2) LTE: As he was trying voice, he did not have coverage. He immediately told me that it's like that for any MCU2, whether "original builtin" as for all S/X since April 2018, or for upgrade like mine and his.
I'm quite surprised here. Owner of S/X with MCU2 just accept this? It would mean 3 years and not enough complain, so this is not being fixed? Feels like this one will never be fixed, and it's crazy.

So to whomever recognise this: "The MCU2 easily don't find LTE or 3G. Almost every time I get in the car, it will not find LTE immediately. After about a minute it connects.", please complain to your SeC. The more attention it get, the more traction it will have.

One thing I saw over the years, is that Tesla is listening, but we have to be loud enough to have the issue pulled out of the back log and into the next sprint.
Our car with MCU2 has no issues connecting to cellular data. We rarely connect to wifi as our garage at home is out of range of wifi. I have noticed that the most recent Tesla app update for iPhone has made the app very slow to connect to the car after opening the app. The issue you describe with it not connecting to LTE is definitely not normal…

We also don’t have any issues with texting. On MCU1 the car could not process replies to texts, but it could read them. Now with MCU2 we can reply too with no issues. We have iOS 14.6. Which iOS do you have right now that is having an issue? Which iOS does the tech have? The duplicating the issue was with your phone & his car or with his phone & your car?
 
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outdoors

Always roaming
Supporting Member
Aug 10, 2014
1,683
2,950
in the moment
We have a problem with Teslawaze within the browser. We are upgraded to MCU2. Each time first time we visit that site we get a complete black out of screens and everything. Car is nice and dark for a bit then it all comes back. Yes the car continues on Autopilot. Turn signals work, but you can't hear them. After the reset site works. Car back to normal. Yet on next drive if you do the same process it does it all again.
PXL_20210719_021125324.MP.jpg
 

AustinP

Active Member
Apr 6, 2015
1,312
1,053
Belgium
Our car with MCU2 has no issues connecting to cellular data. We rarely connect to wifi as our garage at home is out of range of wifi. I have noticed that the most recent Tesla app update for iPhone has made the app very slow to connect to the car after opening the app. The issue you describe with it not connecting to LTE is definitely not normal…

We also don’t have any issues with texting. On MCU1 the car could not process replies to texts, but it could read them. Now with MCU2 we can reply too with no issues. We have iOS 14.6. Which iOS do you have right now that is having an issue? Which iOS does the tech have? The duplicating the issue was with your phone & his car or with his phone & your car?
The text issue is only to initiate a message with the voice command (ie “send message to John”). I can reply fine.
As for LTE, so you mean when you get in your car, it always has immediately LTE working. You don’t need a minute or two before it connects?
 

hybridbear

Member
Oct 6, 2015
750
300
Minneapolis
The text issue is only to initiate a message with the voice command (ie “send message to John”). I can reply fine.
As for LTE, so you mean when you get in your car, it always has immediately LTE working. You don’t need a minute or two before it connects?
It always immediately has LTE. The only time it takes a minute to connect is after a two scroll wheel reboot.
 
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