Charging interrupted overnight

[RedXowner]

Since day 1, I have been charging my car with the charging cable that comes with the car and allows charging up to 40amps. I have a 50amp 240v circuit installed in my garage for this purpose, and I typically charge to 75% for routine, local driving. I always charge my car using the scheduled Ready to Go AT option of being ready at 6:30am, and it typically finishes charging around 5:40am. For the first time since I've owned the car, charging was interrupted after only about 5% of charging had occurred (around 2am), and charging did not restart. Had I been planning a road trip Saturday, this would have been a big deal. Any idea for possible causes? My home power did not go out. The circuit did not trip. It was still powered on when I checked the car the next morning. After I checked the cable, I restarted the charging, and it charged to 75% just like always. In the Tesla app, I scheduled a service, and I described exactly this situation to them. The SC responded and said they would go back and look at that charging session in their logs and see if the cause of the interruption was the car. Glad they are able to do that. Awaiting their inspection and reply. Will post what they say.

Wondering if this has happened to anyone else and what the cause was if you know. Thanks.

 

[DSolie]

The UMC's are finicky beasts. If they sense ANY issue with line voltage, they stop what they are doing. There could have been a slight surge / flux / sine from the house power that the UMC detected and stopped the charging.

 

[SSedan]

One instance I wouldn't think much about, any number of things could have happened.

On the road trip thing, yeah it could happen but if I am travelling I will usually set the car to 90% and then start charging from the app, then soon as I get up in the morning set to 100% if needed to top up during breakfast and showers.

I will say my car acted funny last night too but it seems to have started scheduled charging late. I don't know if the cars "phone home" with the scheduled charging options. If they do maybe there was a server problem last night.
Either way I thought so little of it I had to edit my response to add this because it hadn't crossed my mind in my initial reply. Life is too short to stress over every one off fluke, 2 times in short order start to think about it, 3 times begin problem solving.

 

[Watts_Up]

Any idea for possible causes?
My home power did not go out.
The circuit did not trip.
It was still powered on when I checked the car the next morning.
After I checked the cable, I restarted the charging, and it charged to 75% just like always.

Are you sure that there was no power outage?
- Did you checked, for example, if your microwave clock was not flashing?

Otherwise if there was a power outage long enough for the car going back to sleep (like 5 to 10 minutes)
charging will not start again when the power will come back.

 

[Rockster]

I experienced this repeatedly from my wall connector a few months ago and it turned out to be one of the power connections inside had loosened over time and had scorched/melted. It required that I replace the wall connector. I’ve vowed to pull the cover off and check/re-torque the connection at the first sign of such behavior in the future. Even if you’re using just a 14-50 outlet and the mobile charger this could be a sign of a loose connection in the 14-50 outlet, especially if the behavior repeats.

 

[RedXowner]

Thanks folks. Appreciate the assist. My guess is it was a momentary fluctuation in the power from my provider which caused the UMC to stop and then wouldn't start again. Still waiting on Tesla to diagnose car, but probably nothing.

 

[RedXowner]

Tesla mobile team came to my house and detected something faulty in my Gen 1 UMC. They gave me a brand new GEN 3 charger with wall adapter for my 240 wall outlet. Cool! Did I read somewhere that the GEN 3 UMC can't charge as fast as the GEN 1, which charges at 40amps/9kW? Haven't used it yet. Just got it this morning.

 

[SSedan]

Gen 3 UMC is limited to 32amps

 

[Akikiki]

Yep.

 

[RedXowner]

Bummer. Well now I have both UMCs. I'll use the GEN 3 unless I'm in a super hurry and have to charge at home.