Charging Failure: Firmware Issue, UMC Problem, Charger, or Something Else?

[Todd Burch]

Last night, for the first time since I started driving the S in December 2012, my car did not charge overnight during its scheduled time.

Not to say that it didn't try:

So, I confirmed I had scheduled charging on, starting at 2:30, at 40 amps, charge limit at 90%. Clearly the car tried to start charging multiple times, but failed and seemingly gave up.

So my question is this: is anyone else seeing this? If so, this might be a software/firmware problem. If not, it might be a problem with my power service, charger, UMC, or something else.

I'm contacting Tesla about it to see if they can find anything in the logs, but wanted to see if others are seeing similar issues.

 

[roblab]

Last night, for the first time since I started driving the S in December 2012, my car did not charge overnight during its scheduled time.

Not to say that it didn't try:
View attachment 167540

So, I confirmed I had scheduled charging on, starting at 2:30, at 40 amps, charge limit at 90%. Clearly the car tried to start charging multiple times, but failed and seemingly gave up.

So my question is this: is anyone else seeing this? If so, this might be a software/firmware problem. If not, it might be a problem with my power service, charger, UMC, or something else.

I'm contacting Tesla about it to see if they can find anything in the logs, but wanted to see if others are seeing similar issues.

Have you plugged in your charger to another outlet, or another house?
Have you tried charging with a different charger?
Have you done a general reboot?
How does it work tonight when you retry to charge?

There is considerable that you could do to check it out. I figure Tesla will have you come in to a Service Center and they will do the above.

 

[Todd Burch]

Yep, I'm trying a number of those troubleshooting steps. Mainly I wanted to see if this is abug in recent firmware.

 

[Todd Burch]

Seems like this might be related: UMC repair possible?

Mods, wonder if these two threads should be merged. (Of course it's also possible we both just happened to have almost identical UMC failures on the same night).

 

[scaesare]

Thus far, I've had to clean the lins on my car chargeport and HPWC connector annually (or slightly before) in order to alleviate a problem that can cause my car to drop down to 30A. On rare occasion the charging would enter a start/stop cycle similar to yours.

It appears that dirty contacts cause either the pilot signal or ground pin to cause the issues. After a good cleaning the problem goes away for another 10-12 months.

I can tell when the problem is imminent when my car will lock/unlock/lock the charge port a few times (rather than just once) when connecting the HPWC.... it's having a hard time getting the pilot signal.

 

[mblakele]

Would treating the contacts help? I seem to recall an old post here recommending silicone spray.

 

[thecloud]

A similar stream of "Charging Interrupted" notifications happened to me once last year, at a destination charger, due to a power brownout where the hotel had switched to its backup generators and the charger was simply not getting enough power. It was the hottest day of the year in L.A. (something like 109ºF if I remember correctly) and millions of air conditioning units were crying out in anguish.

Anyway, I'll echo the recommendation to try charging at a different location and see if a problem with your power service can be identified or eliminated. Haven't had any recent problems charging with my UMC. I do have it set to 32A instead of 40A though.

 

[Todd Burch]

It's not a power service issue...been charging there for years, and recently it's happened quite a bit. Plus, it works fine with my other UMC.

SC said they saw a charge cable fault and are going to swap out the UMCs. It's possible the contactors just need cleaning or something similar, but they want to swap it out just to be safe.

 

[thecloud]

It's not a power service issue...been charging there for years, and recently it's happened quite a bit. Plus, it works fine with my other UMC.

SC said they saw a charge cable fault and are going to swap out the UMCs. It's possible the contactors just need cleaning or something similar, but they want to swap it out just to be safe.

Well, if it works fine at the same location (and with the same firmware) using a different UMC, then it definitely sounds like a UMC failure.

I wonder what the nominal lifespan of a UMC is expected to be. Was this your original UMC from 2012, or the one you got in 2014 with your P85? If you've been drawing continuous, multi-hour, 40 amp loads with the same UMC on a nightly basis since Dec 2012, that would be several thousand hours of use. There's definitely a difference in how warm the UMC cable gets when it has to carry 40 amps, so my hope is that dialing back to 32 amps for overnight charging will extend the usable lifetime of my UMC.

 

[Cyclone]

There's definitely a difference in how warm the UMC cable gets when it has to carry 40 amps, so my hope is that dialing back to 32 amps for overnight charging will extend the usable lifetime of my UMC

That's why I charge at 32 amps unless I need to charge faster. So far, no trouble, no noticeable heat (especially compared to 40 amp charging), and not once have I needed to charge faster.

 

[chriSharek]

Glad I went ahead and installed the HPWC instead of relying on the UMC.

 

[Todd Burch]

This was my original UMC from 2012. So it could be an older design, too.

 

[jerry33]

The UMC has been reliable for me for the past three years. They did change out the first one, but that was shortly after I got the car. The only times I get charging interrupted are when there is a power sag (frequently in my area) or I turn on the air compressor while the car is charging or preheating. In both cases it restarts, but at 30 amps (rather than 33 amps).

 

[Edgewood Dome]

Interesting Mine started the same thing on Thursday 3/17 evening. Returned home with about 76 miles of range, plugged in into the 40 amp charger and it started then stopped charging stating charging was complete. Called the SC in SODO and they asked me to bring it in. When I returned home I watched the car charging at the SC with the phone app, it got up to about 56 miles then started slowing down the amps and stopped at 56 miles. I received at notice that the car had completed charging with the charge limit set at almost max. So it is repeatable. Yesterday, Friday, they said is was a failure of a component in the pack itself and they would put in a loaner pack and send mine to the factory for reconditioning.

Now that I see others had this happed at the same time, leads me to think it is something else. As far as I know there was no firmware upgrade.