Welcome to Tesla Motors Club
Discuss Tesla's Model S, Model 3, Model X, Model Y, Cybertruck, Roadster and More.
Register

MCU fails for the second time

This site may earn commission on affiliate links.
Had my MCU replaced a month ago when it died — car was driveable but would only charge at about 280W net to battery, so too slowly to be practical. The usual rebooting didn't work, nor did pulling the main fuse under the phone guidance of the Ranger.

That’s odd. I didn’t realize the CID played an active role in charging. It holds the scheduling and charging amp data requests from the owner, but only the gateway should be needed in theory.
 
That’s odd. I didn’t realize the CID played an active role in charging. It holds the scheduling and charging amp data requests from the owner, but only the gateway should be needed in theory.

I had the same result when mine died, couldn't charge more than 2a. I think it has something to do with not being able to get the location data for geo settings. I didn't try but Supercharging should have still worked
 
Thanks @demundus , I'll hold off a bit hoping but not expecting a new improved unit..

I haven't kept up with this new unit talk, I'd be wary on if its worth it (are you in warranty?) and if its worth waiting. One day your MCU wont turn on and you'll be unable to charge and turn on the AC amongst other things. If it really is the Tegra, there are people here who can replace just THAT chip. @tedsk comes to mind.
 
when mine broke (when i broke mine :( ) I couldn't charge, hence the urgency to get it fixed
That's what happened to me at first. After I pulled and replaced the main fuse, at the behest of the Ranger, the car would charge again. However, it was just at 2A (240V) just as @Lukez said above. With a cold battery — it was 0-4ºC in my garage — I presume that the efficiency of charging was further reduced, hence my rough estimate of just 280W net to battery.

While I'd love to know whether Supercharging would work, the nearest Supercharger Station is 100 miles away, so no way to check on that.
 
Last edited:
I haven't kept up with this new unit talk, I'd be wary on if its worth it (are you in warranty?) and if its worth waiting. One day your MCU wont turn on and you'll be unable to charge and turn on the AC amongst other things. If it really is the Tegra, there are people here who can replace just THAT chip. @tedsk comes to mind.

I'm under warranty for another 30K miles so I'll get it done soon before I have bigger problems..
 
My new MCU rebooted itself a few days ago while driving. This is starting to piss me off. I just had it replaced last year. If it waits until after the one year warranty anniversary to go out and I have to spend another large sum of money, Tesla will see a lawsuit from me. The MCU problems are the main reason I canceled my Model 3 order. GEESH. What happens when the only display on the car reboots itself while driving? (or goes out)

I know the last software update is probably the cause from what others are saying but I am losing faith here.
 
My new MCU rebooted itself a few days ago while driving. This is starting to piss me off. I just had it replaced last year. If it waits until after the one year warranty anniversary to go out and I have to spend another large sum of money, Tesla will see a lawsuit from me. The MCU problems are the main reason I canceled my Model 3 order. GEESH. What happens when the only display on the car reboots itself while driving? (or goes out)

I know the last software update is probably the cause from what others are saying but I am losing faith here.
I wonder if it's related to 2018.6.1. My one week old new replacement MCU had a reboot while driving the day after replacement, and yesterday it was completely out when I got in my car (with the dash screen very dim). I'm also starting to get pissed off by this. Yes, forcing a reboot helped to turn it back on, but I shouldn't need to be forcing reboots on my car like this.
 
  • Like
Reactions: Sudre
@MIT you may be correct ... My car stroked out with the same description when I got the latest firmware. Last week.
Had to reboot it completely.
Turn signals went silent. Entire middle screen very dark and completely non responsive ... to me, it seems like with every firmware downgrade the car gets worse :(
I usually ignore the downloads. Silly me.
 
FWIW, our 2012 P85 is in for service and I had asked if they could replace the screen since it is bubbling. When i asked if it is screen only or also with MCU, they said the MCU would be replaced too. After reading this thread, I asked if it would be the new style or old and they said they wouldn't know until it arrived. I asked them to hold of unless its the new style, but we'll see how that goes.

We have a loaner P85+ hat is a 2013 or 14 and the screen seems laggier than our 2012.
 
FWIW, our 2012 P85 is in for service and I had asked if they could replace the screen since it is bubbling. When i asked if it is screen only or also with MCU, they said the MCU would be replaced too. After reading this thread, I asked if it would be the new style or old and they said they wouldn't know until it arrived. I asked them to hold of unless its the new style, but we'll see how that goes.

We have a loaner P85+ hat is a 2013 or 14 and the screen seems laggier than our 2012.

Why would you get the new mcu? The wiring is totally different