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Charge Rate reduced

I charge on a single phase 32A outlet. Recently the car has been turning itself down to 17A and will only go back to 32A if I reset the charging. Tesla service told me that this is a known bug in the recent firmware but I can't find any reference to that on the forums. Anyone else have this problem - anyone found a solution?
 
Here is a picture

Screenshot_20200804-203132_Tesla.jpg
 
I've seen some other folks on this forum complain of similar issues, but the cause was always a faulty UMC or Wall Connector, or faulty wiring going to it. The symptom was that it would charge at full speed for a while (e.g., 30 minutes) until it got too hot, then the charge speed would turn itself down to protect the equipment.

If you have the ability to test using a different outlet, different UMC, different location, etc, you should be able to determine if the problem is really a hardware issue vs a software problem.

Good Luck.
 
The UMC has status lights you can decode. It’s likely a thermal fault.

Here’s a link to the Tesla Gen 2 UMC: https://www.tesla.com/sites/default...ocs/gen_2_umc/Gen2_Mobile_Connector_en_JP.pdf

I’ve reduced my charging from 32A down to 24A since it gets above 85 F sometimes in the garage when charging during the summer. Mine has shown thermal faults a few times this summer. Almost always it’s the plug or the receptacle itself.
 
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texas_star_TM3

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Oct 28, 2019
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The UMC has status lights you can decode. It’s likely a thermal fault.

Here’s a link to the Tesla Gen 2 UMC: https://www.tesla.com/sites/default...ocs/gen_2_umc/Gen2_Mobile_Connector_en_JP.pdf

I’ve reduced my charging from 32A down to 24A since it gets above 85 F sometimes in the garage when charging during the summer. Mine has shown thermal faults a few times this summer. Almost always it’s the plug or the receptacle itself.

my garage is between 85F to 95F in late afternoon/ evening with the sun beating down on the metal door ... if i dial down to 24A i do not get any overheating warning... running 32A will trigger overheat warning and reduce to 16A. I'd rather charge consistently at 24A vs. going back up/down from 32A to 16A and overheating the UMC. *zero* issues in fall/winter with a cold garage.
 
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Since upgrade to 2020.28.6 the 32A charging seems to be stable.

However dropped in to the Edinburgh supercharger today as I needed a top up. Edinburgh is limited to 130kW but I only got 100kW briefly before the charge rate dropped to 80kW. Batter was at around 100mile range and I topped it to 200 Miles. Wonder why?
 
Since upgrade to 2020.28.6 the 32A charging seems to be stable.

However dropped in to the Edinburgh supercharger today as I needed a top up. Edinburgh is limited to 130kW but I only got 100kW briefly before the charge rate dropped to 80kW. Batter was at around 100mile range and I topped it to 200 Miles. Wonder why?
As it beings to charge, the max rate will drop.
 

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