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

Can anyone with new MCU can repro a charging issue?

This site may earn commission on affiliate links.

whitex

Well-Known Member
Sep 30, 2015
7,462
9,531
Seattle area, WA
I ran into a new issue I've never saw before. New S75D, new MCU. It charging along at 48A happily. I had it set to 100% for a morning trip. Once it got to ~95% I lowered the set SoC to the usual daily limit which was below the current SoC as I've done before on our other Teslas no problem. The car stopped charging ok, but then threw a charger error and red light around the charge plug. Tried the charger on another car, worked just fine even at 80A but the new S75D kept throwing the same charge plug error. I left the car locked for 15 minutes, came back, charging fine. Tried the same thing, lowering the set charge point to less than current state of charge, got the same error!

Can someone with a new MCU car check what happens on your end when you lower the set charge below current state of charge. The charging should stop of course, but then does the error show up?
 
What firmware do you have? There were issues with 2018.14 which is why it was pulled and the new 14.2 tested over the weekend and now is rolling out with a new version of it (2018.14.2 a88808e). Point is, some of those issues were charging related. I don't remember anything like this, but you never know.
 
What firmware do you have? There were issues with 2018.14 which is why it was pulled and the new 14.2 tested over the weekend and now is rolling out with a new version of it (2018.14.2 a88808e). Point is, some of those issues were charging related. I don't remember anything like this, but you never know.

Running 2018.12. Asking if anyone else can repro to try to ascertain whether this is an issue with my car or a software issue. If it's the on board charger that is dying, I want to be proactive replacing it rather than getting stuck somewhere without the ability to charge.
 
  • Like
Reactions: boaterva
Hi Whitex,

I just tried your test. 3/18 Build X-100-D MCU2 2018.14.2
All charged... I increased the charge setting to start the Gen 2 Wall connector.
It was charging for 3 minutes at 72A.
I reduced the charge setting to below the current charge level.
In about 20 seconds the message came "Charging Complete."
The ring around the plug on the car was and is green...

Could be your software level...

Shawn
 
  • Like
Reactions: whitex
Hi Whitex,

I just tried your test. 3/18 Build X-100-D MCU2 2018.14.2
All charged... I increased the charge setting to start the Gen 2 Wall connector.
It was charging for 3 minutes at 72A.
I reduced the charge setting to below the current charge level.
In about 20 seconds the message came "Charging Complete."
The ring around the plug on the car was and is green...

Could be your software level...

Shawn
Thanks! The car just got .14 so I'll try again soon (wife's car, don't want to hang the charger mid-day when she tops it off between running kids around).
 
Checked last night. Still occuring on the .14 build for me. Interestingly enough it doesn't happen with a 40A mobile connector, but happens with HPWC (older style without side dock or load balancing). I also noticed that the car sometimes shows 0/47A and sometimes 0/48A when plugging it into the HPWC, so now I'm wondering whether the issue is that the onboard charger is flaking out (hence reporting 47A as max sometimes instead of 48A). :( I was really hoping this would be our first Tesla without "teething pains" (i.e. requiring service visits withing first 3 months of usage)...
 
Hi WhiteX,

Please let us know the complete string of your firmware 2018.14 was defective and immediately held.

If you have 2018.14.2 that is current and good.

Not trying to be a wiener, but technical problem diagnosis is a precision process... :)

I may be misunderstanding you, but the maximum current for the newer cars is 72 Amp limited by the internal charger
for your home charging. Supercharging is different.
If your HPWC Gen 1 is limited by you to 48 Amp, a flicker of a reading of 47 Amp. is not a problem...
The red ring is definitely a problem...

Shawn
 
Hi WhiteX,

Please let us know the complete string of your firmware 2018.14 was defective and immediately held.

If you have 2018.14.2 that is current and good.

Not trying to be a wiener, but technical problem diagnosis is a precision process... :)

I may be misunderstanding you, but the maximum current for the newer cars is 72 Amp limited by the internal charger
for your home charging. Supercharging is different.
If your HPWC Gen 1 is limited by you to 48 Amp, a flicker of a reading of 47 Amp. is not a problem...
The red ring is definitely a problem...

Shawn
Firmware 2018.14.2 a88808e. AFAIK 75D's only come with 48A charger. 100D's and P100D's come with 72A charger, unless that has changed this month (the car is March 2018 build). The HPWC in question here is on a 100A circuit, so 80A capable (I use it at 80A without problems on an older MS with dual chargers).
 
Rebooted the HPWC, same behavior. Tried at 40A limit, one time it worked, but the second time it threw the same error when completing the charge. The max current limit dipped to 46A during my testing plugging/unplugging/starting-charging/stopping-charging. I have a new HPWC coming as my referral reward but not sure when that's getting here. Once it does and I install it, I can compare new to old HPWC.
 
I had the same thing happen with MCU 1. For some reason it kept trying to charge at 48 amps when I only have a 24 amp adapter. lowering the amps all the was to 12 and slowly bring it back to 24 fixed it for some reason
In this case I have 80A capable adapter (HPWC, I use it at 80A on a second car) and the car charges at 46-48A, just throws an error every time charging completes (so at the end of charging, at least I haven't seen it do that in the middle, it might have and then restarted charging).
 
Update, the car now throws the same error before charging as well, at least it did when I tried charging it today immediately after driving (before I was plugging it in after some parked time as we're sharing one HPWC for 2 cars while we can't park inside the garage for a couple of weeks).