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Car won’t charge on HPWCs/UMC, says check Wall Power

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#21
Yeah, only a few around and none close by I know of. One visitor (local relative) whose person moved. :D

But the real problem is that it’s so variable all of a sudden. If it’s really neighborhood power that’s going to be interesting. Car has been plugged in 99% of the time since September and never had a problem until Saturday. Very weird.

Too bad we can’t get any details on what’s ‘bad’ about the power if that is even it. Anyone got a good source (logging even) for something to install to track power quality?
 
#22
boaterva said:
Yeah, only a few around and none close by I know of. One visitor (local relative) whose person moved. :D

But the real problem is that it’s so variable all of a sudden. If it’s really neighborhood power that’s going to be interesting. Car has been plugged in 99% of the time since September and never had a problem until Saturday. Very weird.

Too bad we can’t get any details on what’s ‘bad’ about the power if that is even it. Anyone got a good source (logging even) for something to install to track power quality?
Click to expand...
It's not unheard of for the utility to be willing to place a logging device to help diagnose a possible power problem. However, it would help if you could tell them what you think might be wrong. Perhaps Tesla would be willing to talk to them?
 
#23
Excellent idea, but the problem is, so far, Tesla has no real data. I would think they would log more than the car displays, but they don't seem to. I don't know if the power company would cooperate based on so little reports.

The car only says on the IC: 'Check charger power' (meaning the HPWC/UMC input) and then after about 15 seconds, you get the flag coming up warning you that 'no power' is being fed to the car. Which I doubt is strictly true. Do we know how the HPWC 'decides' to close the contactors to complete the circuit?

I'll have more evidence when I try the UMC on a (different) 15 Amp circuit. So far, everything has technically been on the same 100 Amp circuit with three different pieces of hardware.
 
#25
Yeah, I’m not convinced this is a high voltage issue. But so far I can’t repro this. It’s happened Saturday and Sunday around noon. Sunday it fixed itself as I left the car plugged in for Tesla to run tests on. Today I’ve plugged it in a half dozen times and it’s always worked.

If it’s either the car or the WC it’s definitely weird.

Interesting above that the 3 gave a concrete error message.
 
#26
See if they'll test your home setup with a loaner vehicle, both immediate charging and scheduled after it's plugged in a while.

Also see if you can test your car against a 240v *residential* source somewhere else, preferably a town or two over (my service manager used the HPWC in his house about 50 miles away from mine overnight a couple times). If they just test on the HPWCs in the shop or most public level J1772 charger, those are likely two legs of three phase at 208 volts, way lower than a 240 volt residential circuit. If a voltage sensor in the car is out of whack it'll behave differently and probably work where another 240 volt source won't.
 
  • Informative
Reactions: boaterva
#27
Thanks for the comments and all that is well and good but the reason I’ve not added anything is that since the weekend charging hasn’t failed. Sort of hard to troubleshoot/test things when it’s not broken!

And now we have 2018.20.5 coming out. Slightly suspicious if some weird combination of things triggered this and we have a new version of software. All hard to verify since 20 never had a large rollout. I think this weekend may be the test, if the problem recurs or not!
 
#28
I ran into this problem over a year ago with our S P85.

Our garage has an HPWC on a 100A circuit - and a 14-50 outlet.

When the car started having charging problems on the HPWC, I tried using the UMC on the 14-50 outlet - and ran into the same charging problems - charging would not start, or if it started would stop after a few minutes.

I even tried using a 110 outlet - and had the same problem.

I called Tesla - they looked at the logs - and they believed the car's charging system was OK.

The utility ran there standard power check - and we were getting the correct voltage.

It turned out, other Tesla owners were having the same problem within several miles of our house.

After getting Tesla and the utility to talk to each other - the utility discovered problems in their distribution equipment in the area - which was introducing some noise on the power lines. It wasn't enough to disrupt most electrical devices - but was enough to prevent the Tesla chargers from operating reliably.

It took almost a week until they were able to do a trace through the grid equipment - and find the cause and repair it.

NOTE that when this happened, the normal power technicians probably don't have the equipment to test this. They had to install a special logging device on our circuit to do a more detailed analysis.

If you're seeing charging problems on both UMC and HPWC, my advice:
  • Take your car somewhere else and try to charge using your UMC or a public J1772 or destination charger. If that works, then you've probably ruled out a problem with your UMC or onboard charger(s).
  • If you know any Tesla owners in the area - check to see if they are having issues. If not, take our car over there and see if your car charges.
  • Call Tesla's phone support to have them look at the logs for your car, and see if they find any charger warnings or faults.
  • Call the nearest Tesla Service Center to see if they are having reports from any other Tesla owners in your area
While it's most likely a problem with your onboard charger(s), it's also possible you may have a problem with the power inside or outside of your house - and it may be more complicated than just verifying voltage levels.

WARNING - Tesla assured me the car's charging equipment was protected from damage due to power problems or surges. But, despite that, the secondary charger on our S P85 (which had the dual 40A chargers) blew out during this time. This was covered under our extended warranty - so it is possible for bad power to damage your onboard charger...
 
#29
We'll keep all these suggestions as great stuff if and when it comes back. I think the 'green' symbol I see in Remote S tells me the charger is happy, because when the car is 'resting', it's green (on the car and in the app) even though it's not using anything. When it breaks, you plug it, it goes blue, and that's it. Never handshakes or something (for whatever reason).

I just came back from a trip, and of course it's fine.

It has never failed except for the several times last weekend. And one of those 'cured' itself, as noted way above. Tesla is now/still waiting for me to tell them we have a test case, so they can send the mobile Ranger unit to plug in their self-contained UMC.

I can think of reasons that power would be 'bad' on the weekends, but not why it's bad now and not for the past eight months. We'll see how it does tomorrow and onward. The other issue is that them looking at the logs produced nothing except a general 'your power has to be bad'. No specific high/low/what exactly.
 
#30
The issue with our power was damage caused by a storm, resulting in surges that evidently damaged the grip equipment. Evidently the Tesla chargers are more sensitive to this type of "bad" power - and took a while for the utility companies to trace which circuits were affected and then back trace to the damaged equipment.

The electric utility repair staff normally deals with voltage fluctuations - trying to detect noise being introduced into the power is unusual - and they usually don't carry the equipment to detect that type of problem - which could be constant (fortunately, what we were experiencing) or possibly intermittent (which will make it even harder to correct).
 
  • Informative
Reactions: davewill and boaterva
#31
I’m up in OC for the week and am having charging problems with my UMC. It has worked here on same 14-50 plug fine.

Saturday I got a momentary fault during the day and thought a kid may have played with the plug . Restarted it and it took off charging and stopped again within 7 miles of charge. Error stated to check power source. Voltage was at 251v all day would not charge. Several failures.

Came back late at night plugged in at 248v now and charges fine to full charge.

I also had read charger only goes to 250v max on a post as well as in the HPWC book. So will it monitor within a volt?

Is there a instruction book or at least I list of fault codes for the UMC?

Boaterva I have a power quality meter if you need to run a test.
 
#32
The meaning for the HPWC light codes are in the manual. Thanks for the meter offer, but I've had no issues since the weekend, a week ago. Sigh.... It was a hot weekend then, but WTF....

I may have to get some sort of recording meter to see what's up here. But if never recurs, I'm not sure what to do next!
 
#35
It’s a high end Fluke that records events for weeks. I know frequency is on it. We record on various job sites for weeks trapping events. Mainly voltage and amps.

Also I just charged at holiday inn and the voltage was 250. Once the amps started flowing the voltage dropped to 245v.
 
#36
Reddy Kilowatt said:
It’s a high end Fluke that records events for weeks. I know frequency is on it. We record on various job sites for weeks trapping events. Mainly voltage and amps.

Also I just charged at holiday inn and the voltage was 250. Once the amps started flowing the voltage dropped to 245v.
Click to expand...
Yeah, I noted the same on mine. No load voltage was 246 or so, TeslaFi seems to usually record 240-242 when charging.

If you could pass along the model number of that Fluke, I’d like to check it out!
 
#37
I’ll get the model number this week when I get home.

Here is the latest. The car stopped charging with the UMC. charged up at holiday inn.

The M3 charged fine with my UMC and same outlet before it’s update.

Tried to charge multiple times no luck just after the M3. Unplugged and stored UMC last night.

Called Tesla spoke to them. Single red flashing light on UMC is a ground fault

Car charged fine this morning with 245v dropping to 240v

Tesla sent me 2018.21.9 update with warning on updating UMC might require two minute update, which I didn’t get. The M3 got Tesla update last night before charging. I wonder if it updated the UMC for me.

Car is now charging to 100% in the pouring down rain.

And just tripped at 99% ??
 
Last edited:
#38
Wow..... And I’ve still not had a problem in two weeks. Charging fine today also. WTF. I’m still wondering if 2018.20 is involved somehow... and if that is why a weird numbered release is rolling out at full speed? Perhaps a conspiracy theory....

(Thanks for checking on that model number when you can!)
 
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