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Return of phantom 16 amp charging

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Looks like I may be suffering from this too, though like another poster I wasn't sure if it was just down to a new charger as I've just had a Zappi2 installed to replace my old dumb BMW wallbox that had gone faulty. Up until the BMW unit went faulty (would no longer handshake with the car) it charged without issue (had the Model 3 since January). Once it was broken I was basically just having to use the Granny charger and it was while I was stuck using the Granny charger that I updated to 2020.20.12. My first proper charge on the Zappi was last night during my Octopus Go hours (00:30-04:30) and although it began OK at 32A (well 30A initially as the installer hadn't adjusted the device limit up to 32 which I fixed shortly into the charge), when I looked at the logs this morning it dropped to 17A at exactly 2am and stayed there for the remainder of the charge up until 0430. The car had begun the charge with 34% battery and at 2am when the current dropped to 17A it was at 47%, and finished on 60% at 0430 (the target charge is 80% so I was nowhere near that). Looking at the Teslafi logs it appears the pilot current remained at 32A throughout so I assume it was the car causing the issue.

I wasn't sure if it was because I had moved from the dumb BMW charger (just using the in car timer to begin charging at 0030 and using Teslafi to stop at 0430), to using the Zappi to control the charge (left the car to charge straight away and set the Zappi to Eco+ and boost timer between 0030-0430, and using Teslafi to wake the car at 0025 to ensure it could accept the charge when the Zappi started it). I am planning to use the Zappi in dumb mode tonight and go back to using the car timer / Teslafi to manage my offpeak charge so I will see if I get a different result before i raise a service request.
 
I am planning to use the Zappi in dumb mode tonight and go back to using the car timer / Teslafi to manage my offpeak charge so I will see if I get a different result before i raise a service request.

Symptoms do sound like the present charging issue with the car. We just need to collect the evidence from a few charges (that's what I'm doing anyway).
 
Mine charged OK last night as well....
It’s this inconsistency that’s really doing my nut in...

I'm also facing the same issue. The fact it's intermittent is intriguing.

Searching for commonality through my Teslafi logs. I've noticed a trend in mine which I would like someone with Teslafi and the issue to verify.

My charging seems fine and dandy at 32a when voltage is less than 230v, as soon as it creeps above 230v Teslafi records charging drops to at 18a. Witnessed this on several charges.

Thoughts?
 
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I've noticed a trend in mine which I would like someone with Teslafi and the issue to verify.

My charging seems fine and dandy at 32a when voltage is less than 230v, as soon as it creeps above 230v Teslafi records charging drops to at 18a. Witnessed this on several charges.

Thoughts?

Looking at my Teslafi logs it does seem voltage related, although in my case the cutoff is 238v. At that I get 32A, once it goes over that I get reduced A. Seems to vary A around 17 to 20 up to around 242v, anything beyond that I just get 17A.

Bummer as historically my voltage is stable in the high 240s...
 
Interesting observation but in my case it's definitely not related to a higher voltage. My voltage during charging is never above 225v.

Would you mind having a look at around 4am this morning on any logging too you have which records voltage. There are a number of people reporting an "event" which correlates to voltage, and at the exact same time power demand was high (seen in frequency charts) calling for an increase in voltage.

This is mine -
Screenshot_20200628-114205_Chrome.jpg
 
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Variance from some perceived initial voltage maybe? While you may never go above 225 do the lower amp points coincide with higher voltage points relative to the start voltage?
Are you sure that you’re not just seeing the voltage rise as the current decreases? Depending on cable lengths etc it’s quite normal to see a voltage drop as the current rises, and vice versa. On my last charge the voltage was 227V at 32A, but rises to 240V at 17A. This is normal on my installation.
 
Variance from some perceived initial voltage maybe? While you may never go above 225 do the lower amp points coincide with higher voltage points relative to the start voltage?

I have a long run from the house to the garage area where the charger is located so the start voltage (no demand) is 240ish but takes a significant drop when pulling 32amps ... as I say, to around 225 or lower. I don't have Teslafi or Teslamate so I only see the voltage when I look at the app or the screen in the car so I can't follow how it varies over the full course of a charge and link that to the changing rate.
 
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Looking at my Teslafi logs it does seem voltage related, although in my case the cutoff is 238v. At that I get 32A, once it goes over that I get reduced A. Seems to vary A around 17 to 20 up to around 242v, anything beyond that I just get 17A.

Bummer as historically my voltage is stable in the high 240s...
I think you are on to something but it may not be absolute voltage but the variation. I did not think I had suffered this but I have been back through my logs and actually I have on 2 occasions and yes they seem to coincide with a rise in voltage. in my case from 230 to 236. It states in the Tesla manual.
"
NOTE: If Model 3 is charging and detects unexpected fluctuations in input power, the charging current is automatically reduced by 25%. For example, a 40 amp current is reduced to 30 amps. This automatic current reduction increases robustness and safety in situations when an external problem exists (for example, a home wiring system, receptacle, adapter or cord is unable to meet its rated current capacity). As a precaution, when Model 3 automatically reduces current, it saves the reduced current at the charging location. Although you can manually increase it, Tesla recommends charging at the lower current until the underlying problem is resolved and the charging location can provide consistent power.
"
I appreciate that we are seeing a 50% drop not 25% but could this still be related? have they made a change to this in 2020.20.12 and the car is now interpreting what seem to be normal UK fluctuations in voltage as "unexpected fluctuations in input power" and thus reducing the charge current deliberately. If that is the case it looks as if they have made it way to aggressive, either on purpose or accidently since I have been charging fine for 7 months without issue it seems unlikely that reducing the current is necessary for me and probably for the rest of you as well.

or alternatly it may be as Roy said that the voltage is a result of the change in current not the cause but I still wonder if the problem is related to this functionality?
 
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Are you sure that you’re not just seeing the voltage rise as the current decreases? Depending on cable lengths etc it’s quite normal to see a voltage drop as the current rises, and vice versa. On my last charge the voltage was 227V at 32A, but rises to 240V at 17A. This is normal on my installation.

I didn't pay enough attention in my GCSE physics to know which is cause, and which is effect I'm afraid, so yes - you absolutely could be correct. We'll have to await someone cleverer than I to comment.
 
the car is now interpreting what seem to be normal UK fluctuations in voltage as "unexpected fluctuations in input power" and thus reducing the charge current deliberately. If that is the case it looks as if they have made it way to aggressive, either on purpose or accidently

That seems it to me, but as I said in a previous post, I'm not electrically competent to determine if what I'm seeing in the TeslaFi data is a cause or an effect. Either way there does appear to be a bug somewhere, and it only started (for me) after the 2020.20 install. The fluctuations I see in my data are well within "spec" for UK mains electric which should support 216v to 253v...
 
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Well last night things seemed to remain at 32A right up until it hit 80% charge at 03:08. This was using fast (dumb) mode on the Zappi and doing timing via the car and Teslafi.

I don't expect to use the car much over the next few days but towards the end of the week I will be back doing a 60 mile round commute so should get a chance to monitor over a few consecutive days. I will try some days charging like last night and others using the Zappi to handle the timing instead to see if there is a pattern.
 
Since updating to 2020.20.12 charged twice, the first time charged at 32 amps as it normally does, last night started charging at 32 amps then after an hour reduced to 16 amps for the rest of the charge. I’ll see what it does tonight when It’ll complete the charge (I hope).
 
I think we should rename the thread “Phantom 4.2kW charging”.

Just a theory: Owners are reporting different reductions: 16/17/18A. If you check each person’s screenshot and do P=IV, the reduced charge is consistently about 4.2kW. The app doesn’t show the decimal for kW or Amps but it does seem consistent.
 
Got me again last night. I needed a decent charge today so set the alarm for 4am just in case. Lo and behold, half the normal charge rate. Bleary eyed I reset it and off it went and seemed to maintain at 32amp. Getting annoying now.

Also when I was out I got the incoming call not connected issue which then shut off all cabin sounds. Waited a couple of minutes and then all came back including Spotify at full blast! I submitted a bug report or at least I tried to because voice control also seems to have gone backwards. All that and intermittent Sentry functionality leaves me wondering if Tesla's main software guys are all high.

This last update has been a crock to be fair!
 
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