Problems with home charging after over a year of charging with 240 V 30 A

[Sans-gas]

I’ve been having increasing problems charging at home after no problems for over 16months.

I have a 240V 30 A circuit where I plug the Tesla Mobil charge cable. I generally have it scheduled for 10pm but only need to charge ever other day (when I’m under 45%) in my M3 LR RWD.

In the last few months I'v had increasing trouble initiating charging at times other than at the scheduled time. For instance if I go plug in the cable later in the evening and try to start it will indicate it’s charging (with green lights blinking on port and wall charger), but it is not charging (0 kW, 0A, 240V) on the screen. I get a text message on my cell after 10 min that charge was interrupted.

When I look at the port then, the “T” is red.

After communicating with Tesla svc, they suggested I turn off the schedule, and remove any 3rd party apps. I did all this, as well as change my Tesla password. But I’m still having issues that seem to be temporal. I can nearly ALWAY initiate home charging in the AM, but not in the evening.

We’re NOT having brownouts or outages in the house. The wall outlet tests appropriately at about 240. We have no TV or electronics that are starting or stopping routinely.

I’m keeping a log and last night I went to test it out so I have a record when I go for service in a few weeks. It then DID charge in the evening, when I had expected a failure. What the heck!!

Anyone? I have a friend who’s going to loan me his mobile charge cable to test out, but it hasn’t happened yet.

 

[Puddles]

My charge cable controller failed, and displayed an undefined code, which did not encourage Tesla to be of any help. I wonder if yours is going out too. Any way you can try another charge cable?

 

[MOMedic82]

This sounds a lot like what we're experiencing and talking about in this thread:

Charging Issue Level 2 at Home

 

[Sans-gas]

My charge cable controller failed, and displayed an undefined code, which did not encourage Tesla to be of any help. I wonder if yours is going out too. Any way you can try another charge cable?

The friend’s Tesla Mobile charge cable also failed. Bummer!

 

[XLR82XS]

May be an issue with your breaker/wiring.

 

[Sans-gas]

It’s always a possibility but, not likely since it’s been perfect for over a year.

 

[user212_nr]

After communicating with Tesla svc, they suggested I turn off the schedule, and remove any 3rd party apps. I did all this, as well as change my Tesla password. But I’m still having issues that seem to be temporal. I can nearly ALWAY initiate home charging in the AM, but not in the evening.

I think continuing to communicate with Tesla is the solution here. The V3 wall connector has overheating issues, if that is what you have.

It would be useful to setup your charger on wifi so that it can get firmware updates, if you have not already.

 

[Sans-gas]

Mine has not overheated. That would raise my concern. The car is in service now.

 

[camalaio]

Only just seeing this thread now, but glad it's in service now.

For the future, the car generally tells you a lot. For the cases where it's predictable (e.g. the evening), sitting in the car for a minute or two and waiting for the error to appear is best. It'll usually pretty clearly tell you why it couldn't start (or stopped) charging.

IMO showing 240V on-screen but 0A (especially if indicating 0/24A, for example) indicates it's a car-side issue of some sort, but that can vary from quite cheap fix to very expensive part.

 

[toolman335]

Have you tried 120 or supercharging?
You have to eliminate variables to make sure it's not the car.

 

[Sans-gas]

I have tried 120. It worked all 3 times I tested it. It seemed to require more time than I would have expected, though I didn’t run the numbers. If it was going to be 6 hrs on 240V, it would show 120V (actually 110) would take 16-19 hrs. I did rely on it for juice a couple times, as a stop gap measure.

 

[Rocky_H]

It seemed to require more time than I would have expected, though I didn’t run the numbers. If it was going to be 6 hrs on 240V, it would show 120V (actually 110) would take 16-19 hrs.

You're not looking at the whole picture, because you are only looking at voltage. The charging speed scales with power, which is in Watts, and is volts times amps.

So when you say 120V versus 240V, they were also probably different amps, and you didn't look. So was it a 15A circuit? 30A? 50A? If the amps were the same, then yes, the doubling of voltage would be about double the charging rate. But the 120V circuit was probably also less amps than whatever 240V circuit you were comparing it to.

 

[AlanSubie4Life]

You're not looking at the whole picture, because you are only looking at voltage. The charging speed scales with power, which is in Watts, and is volts times amps.

So when you say 120V versus 240V, they were also probably different amps, and you didn't look. So was it a 15A circuit? 30A? 50A? If the amps were the same, then yes, the doubling of voltage would be about double the charging rate. But the 120V circuit was probably also less amps than whatever 240V circuit you were comparing it to.

Also, the charging overhead of ~250W impacts 120V charging rate significantly, at least the typical 12A or 16A 120V charging.

 

[RheesB]

Our M3 LR AWD charged on a 120V receptacle all summer just fine. Ran 12A and we got 5 mph. A couple of updates ago it started giving us intermittent "Charge interrupted" messages. It sits at 120V and 0 amps with occasional trips to 1-2 or even 3 amps but then drops back to 0. After a bit it tells us charge interrupted.

As time has gone on it has stopped charging altogether.

So, I installed a 240V 30A receptacle and it still does not charge off of the local utility. But, here's the fun part, we have a 30 year-old 8kW diesel generator that runs the house through a transfer switch and the car charges just fine off of the generator! Same volts, same Hz, and the generator feeds the place through all of the same breakers and panels the utility power does.

Local service guy says he has 7 customers with same issue and "engineers are frantically searching for the fix". Other than that he suggested it was noise on our power line. So, we will put a scope on it and see. Stay tuned.

 

[Sans-gas]

I heard the same today from Tesla Svc Center.

 

[RheesB]

I followed the link to the other thread mentioned above and it is a better place for this message. I copied it to there.

Charging Issue Level 2 at Home

 

[Sans-gas]

I count 7 of us here on this site. It’s not many, but Tesla is aware of the issue.

 

[BrownOuttaSpec]

The friend’s Tesla Mobile charge cable also failed. Bummer!

1. Can you go over to your buddy's house and try to charge there with your 240v charger? Does it work fine there?
2. You said that 120v works but its ways slower, that is very normal. 240v * 30 amp is 7,200 watts. 120v * 12 amps is 1,440 watts. Add in the fact of waste heat energy and pumps/fans/other computers running and that's probably 200 watts. So the real difference is 7,000 watts vs 1,200 watts so it will be way slower and 'not just half as fast'
3. You said it worked fine for a year, so why stop working now: Check your plug because the wires get hot when charging and expand and cool off when not charging and shrink so the connection could have come a bit loose on the receptacle (especially if you have a cheaper 14-50R outlet: See this post for examples: Definitive 14-50 NEMA Outlet Guide)

 

[Sans-gas]

I’ve tested another 240V circuit. It was no better. I’ve not detected a hot cable or connection (I’ve checked). There IS a known issue with some VINs on M3. Those of us impacted are waiting for a fix. I can use SC and 120 V when my 240 fails me. It’s not ideal.

 

[Occhis]

Have you checked the wiring at the 240V outlet and back to the breaker? It’s possible one leg of the 240 cable is not getting power and has a loose connection.