Issues with Gen 2 Mobile Connector?

[owenscameron]

Has anyone had issues with their Gen 2 mobile connector? I have mine plugged into a 14-50 outlet I had installed and the charger will stream green lights and flash red once. However, once I unplug the connector from the wall and plug it back in, it will work just fine.

From what I can see on Tesla’s website, the streaming green lights followed by a single red light indicates a high temperature. But why would it work just fine after unplugging it just moments later if it was a heat issue?

 

[Sophias_dad]

I am not sure how the algorithm works, but it wouldn't surprise me if there's a 'lockout' and an overheat causes the UMC to shut down until power is removed and reapplied. As it sit there (not charging) everything cools off.

 

[3sr+buyer]

From what I can see on Tesla’s website, the streaming green lights followed by a single red light indicates a high temperature. But why would it work just fine after unplugging it just moments later if it was a heat issue?

Perhaps the temperature at the plug was just above the threshold, and the short time between it shutting down due to heat and being plugged back in was enough to allow it to cool below the threshold.

If the outlet is a Leviton 279-S00, you may want to replace it with a different outlet. The Leviton 279-S00 has half size steel contacts to the plug blades which have more resistance (and therefore heat generation) than the full size brass contacts that other outlets have (this can be observed by looking into the plug blade holes). You can also try having the car charge at a lower amperage like 24A to see if that will keep it from getting too hot.

 

[davewill]

Any kind of thermal monitoring will have hysteresis. This means that the temperature they trip at is higher than the temperature they reset at. Otherwise such systems might constantly cycle between tripped and not tripped. The thermostat for your heater or A/C uses the same kind of logic. You set the heat to 70 and the thermostat shuts the heater off at 70, but doesn't turn it back on until the temperature drops to 68 or so. Turning the system off and on can override that behavior and cause the system to turn on at say, 69.

In the case of the mobile connector, I'd expect that it never resets on it's own as the overtemp is not a normal condition. If this happens, it's assumed there's a fault that should be repaired. You'd probably have to unplug at least the car to reset the monitoring, if not the whole mobile connector...and you really shouldn't use it again until you fix the issue that's causing the overheat in the first place.

 

[Aaron M.]

I have had our first mobile connector replaced due to the high temp flashes. The new one worked fine until last night. T turns red and flashes 4 times. I unplugged and it worked fine for about an hour until charged. The plugged was looked at by electrician and he said it was fine. Is this common for mobile connectors to go bad? We have had the second one for about two months now.

 

[RayK]

The plugged was looked at by electrician and he said it was fine.

Do you know exactly who is the manufacturer of the outlet and its model number? If a Leviton of any kind, you should probably get it changed out for a Bryant or Hubbell.

 

[MikeBravo6]

I had the same problem; 4 green LEDs and a slow flashing red indicating a temperature issue. But since the mobile connector wasn't charging and the outside temp was 10C / 50F it had to be something else. The day before this happened the app already showed a speed downgrade from the normal 16Amp/240V to 8Amp so 11kms/hr iso 22. After unplugging and plugging back in it restored to 16Amp again. But the next day charging stopped completely (Red T indicator at the M3 charge port). My suspicion was water seeped in the plug since the silver cover plate was already showing signs of letting loose for some time.
After over 4 years of almost daily use outside the house it finally kicked the bucket...

Now I found a fix, but also ordered a Wall connector today to enjoy higher 3 phase charging speeds and also because I don't trust my Mobile connector anymore for daily use. So everything after this is at your own risk!

Since there no easy way to open up this plug I used a Dremel to free the silicone shield that covers the PCB holding the temp probes (2 apparently) and charge port door switch circuits. There where signs water had seeped in but after cleaning with Iso Propyl Alcohol and drying the temp fault still appeared after a few seconds allowing only 8Amps max.
I first checked resistors, capacitors and the diode, these appeared ok. I then started touching the PCB (max 3.3v) to feel if parts where hot AND to see if a small change in resistance would remedy the problem. If I made contact to pin 1 & 3 the temp fault cleared. There's 4 wires I presume lead back to the mobile connector. I found a 1M ohm resistor between pin 1 and 3 (see pics) was enough to clear this error. Now I did check if the temp fault would reappeared after heating up the PCB to 120C, but that didn’t happen(!) This prompted my ordering a new wall connected demoting the mobile connector to secondary use only. I used hot glue on the PCB itself and for closing the plug up plus extra tape to prevent water ingress in the future.
So it’s a fix, but I would strongly recommend using it at your own risk AND at a lower power setting to ensure overheating won’t occur.