UMC bricked in Cold Weather?

[Bob_00]

Has anyone had an issue with their UMC not working in cold weather? Last night when I plugged my car in in it was cold (-20C or so), and the green TESLA never illuminated, and the app said 'Ready to Charge - Check Power Source'. We have 2 Model 3s so I have one UMC on a 14-50, and the other we just use on the standard 120V. As the 14-50 worked with out issue, my first though was tripped breaker, so I checked an all were on, I also tried a different plug and no dice. So I swapped out the 14-50 adapter and still nothing and the one that was on the 14-50 originally worked on the 120v outlet. Based on all this, I assumed the UMC had just died, so I packed it up and came inside to deal with in the AM.

This morning, out of curiosity, I pulled the UMC out this AM after it had warmed and plugged it in and the TESLA lights came on instantly. Went back out to the original plug and it seems to be all good now.

Can the cold weather temporarily brick the UMC?

 

[Nogasmn]

Definitely, cold weather is the bane to all people charging with 120v.

 

[CrayZ1]

Possible GFI issue? 120 outlets in garages often have GFI outlets or breakers, as do EVSEs. Ice can trigger a GFI event that would not normally occur.

 

[Bob_00]

Possible GFI issue? 120 outlets in garages often have GFI outlets or breakers, as do EVSEs. Ice can trigger a GFI event that would not normally occur.

I checked a non GFI circuit and it was dead as well, and the UMC that was on the 14-50 worked on the garage circuit so the GFI hadn't been tripped. Also, after warming over night, the bricked UMC seems to work again. I guess it is possible the GFI in the UMC tripped. I just though it was curious how it worked again after warming up over night.

 

[Need]

The lowest operating temperature is supposed to be at -30C so -20C should be within range. Is it possible that some water got in between the adapter and the block and turned into ice and shorted the connection or something? This is the UMC that you left outdoor all year long?

 

[Vawlkus]

The UMC isn’t weatherproof, only weather resistant. It’s a small difference, but noticeable. If you’re leaving it outside for extended periods, this will happen.
The HPWC, on the other hand, is weatherproof. That was the key factor for me to upgrade to it instead of relying on the UMC.

 

[5_+JqckQttqck]

Loop the cables in such a way where you can put a plastic shopping bag on it and hang it away from the rain. I do this all the time going camping in the rain

 

[Bob_00]

Thanks for the suggestions. For the most part, the UMC is stored in the garage when not in use, but its possible that moisture has gotten in at some point recently considering the rain. It seems to be working fine now, but I am going to re-organize my garage so I can keep it in doors full time

 

[5_+JqckQttqck]

Thanks for the suggestions. For the most part, the UMC is stored in the garage when not in use, but its possible that moisture has gotten in at some point recently considering the rain. It seems to be working fine now, but I am going to re-organize my garage so I can keep it in doors full time

There are two small holes on the side where it vents heat? Depending on how it's mounted outside. Possible to just tape them up to avoid rain seeping in while still providing air flow (restricted).

 

[martind3]

The issue I seem to be having with my UMC is that below -7 or so the button seems unresponsive. I have to open the charge port from the app or the screen. Otherwise works fine. Only used in the garage. I was going to mention it next time I have the mobile service team over.

 

[noicepls]

The issue I seem to be having with my UMC is that below -7 or so the button seems unresponsive. I have to open the charge port from the app or the screen. Otherwise works fine. Only used in the garage. I was going to mention it next time I have the mobile service team over.

You can also open the charge port door by pressing lightly on the lower portion of the door, if that helps.

 

[corlaandstan]

Has anyone had an issue with their UMC not working in cold weather? Last night when I plugged my car in in it was cold (-20C or so), and the green TESLA never illuminated, and the app said 'Ready to Charge - Check Power Source'. We have 2 Model 3s so I have one UMC on a 14-50, and the other we just use on the standard 120V. As the 14-50 worked with out issue, my first though was tripped breaker, so I checked an all were on, I also tried a different plug and no dice. So I swapped out the 14-50 adapter and still nothing and the one that was on the 14-50 originally worked on the 120v outlet. Based on all this, I assumed the UMC had just died, so I packed it up and came inside to deal with in the AM.

This morning, out of curiosity, I pulled the UMC out this AM after it had warmed and plugged it in and the TESLA lights came on instantly. Went back out to the original plug and it seems to be all good now.

Can the cold weather temporarily brick the UMC?

Has Tesla changed out your charge port yet? We have an Aug'18 build TM3 awd which got a new charge port back in Sept'19. Remote service did the exchange.

 

[VT_EE]

I had the UMC charging on a 120V at the beginning of the evening, but as the temperature dropped into the teens (F) overnight, it stopped charging. I don't think it will charge if the core battery temperature gets too low and a 120V service will not provide enough energy to keep it at a safe charging temperature. I suspect your UMC was working as designed.

 

[5_+JqckQttqck]

I had the UMC charging on a 120V at the beginning of the evening, but as the temperature dropped into the teens (F) overnight, it stopped charging. I don't think it will charge if the core battery temperature gets too low and a 120V service will not provide enough energy to keep it at a safe charging temperature. I suspect your UMC was working as designed.

It will charge after running the motor off the UMC 120V/12A supply for a period to warm the battery to an acceptable temperature to accept the 1.4kW charge rate. The efficiency is abysmal at near 50% or worse. Maybe 5 or 6km/h at best. If you have all weekend, it'll juice up 200~ish kms in total if left plugged in for two days.