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Mobile Connector Problems.

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Hello everyone, need some help troubleshooting a UMC-2.

Outlet: Nema 6-50
Volts: 240
Amps Circuit: 50
Charging Amps: 24

The past month I have been noticing my UMC start charging my MY, about 10 minutes into it charging I get a "Ready to Charge. Check Power Source” message on my Tesla App. I unplug the charger from the car and outlet then replug everything. This seems to solve the problem about 80% of the time. My UMC does sit outside but I cover the UMC box so it does not get direct sunlight. The UMC box itself gives a solid red light. I have had the electrician double check their work but they could not find any mistakes. The reasons why I do not think the UMC is overheating is because this error has came about when plugging the car in at night. I really can not think of any other reasons for this problem. Tesla service says they want a fee to recreate this issue (that can be waived if the problem is recreated), which makes no sense for a warranty car. They say it could be the car or UMC. Is it a possible wiring issue since the UMC does work majority of the time?
 
Can you charge at work or at a public Level 2 charging station? If you can charge at another location that would eliminate the Tesla's charging port as the source of the problem. You would need to use the Tesla J1772 adapter that should have come with the Tesla Mobile Adapter kit.
 
Can you charge at work or at a public Level 2 charging station? If you can charge at another location that would eliminate the Tesla's charging port as the source of the problem. You would need to use the Tesla J1772 adapter that should have come with the Tesla Mobile Adapter kit.
Hello Jcanoe,

Yes, I have been able to successfully charge at multiple Superchargers and only once have I charged at a J1772 Chargepoint charger. All of these sessions were longer then 30 minutes as well.
 
When you use the Mobile Connector do you let the Mobile Connector chassis hang supported by the 6-50 plug adapter/6-50 receptacle or do you have some type of holder for the Mobile Connector chassis (see 2nd photo.) Cable Organizer

Do you leave the Tesla 6-50 plug adapter plugged into the 6-50 receptacle or do you frequently plug and unplug from the 6-50 receptacle? How long have you been charging this way using the Gen2 Mobile Connector with 6-50 plug adapter?
 
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I would make certain that the 6-50 plug adapter is fully inserted into the Mobile Connector chassis. I would suggest using a wall hook or similar hanger and a short bungee cord or a velcro wrap or several plastic tie wraps to take the weight of the Mobile Connector chassis off of the plug adapter and wall receptacle.
 
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Do you leave the Tesla 6-50 plug adapter plugged into the 6-50 receptacle or do you frequently plug and unplug from the 6-50 receptacle?

How long have you been charging this way using the Gen2 Mobile Connector with 6-50 plug adapter?
The only time I have had to unplug it is when I would get the solid red light from the receptacle. Other than that, if it rains I will unplug it.
 
The only time I have had to unplug it is when I would get the solid red light from the receptacle. Other than that, if it rains I will unplug it.
Is there a weather cover for the 6-50 receptacle? Can the weather cover be used while the plug adapter is inserted into the receptacle? Large amperage receptacles such as the NEMA 14-50, 6-50 are not generally designed for a high number of plug and unplug cycles.
 
Is there a weather cover for the 6-50 receptacle? Can the weather cover be used while the plug adapter is inserted into the receptacle? Large amperage receptacles such as the NEMA 14-50, 6-50 are not generally designed for a high number of plug and unplug cycles.
Yes their is a weather cover on the receptacle. I believe it is spring loaded, so it always closes.
 
Yes their is a weather cover on the receptacle. I believe it is spring loaded, so it always closes.
If you are going to continue using the 6-50 receptacle look for a weather shield can be used while the plug is in the receptacle.

I would suggest that whenever you plug or unplug the 6-50 plug adapter that you first turn off the circuit breaker that controls the flow of electricity to receptacle. As there is no GFCI, you could be electrocuted while attempting to plug or unplug the 6-50 plug adapter especially when the ground is wet.
 
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I've been seeing a lot of reports on this forum of bad UMCs with this kind of intermittent failure, and Tesla replaces them--no bother. I'm not sure why they are giving you a hard time about this.
Thank you, Rocky, I appreciate this. I am going to head to the service center in-person and get this taken car of. I have had enough of my vehicle not charging over night. Would you by chance know how I can make s formal complaint about my service problems?


Edit:

I also wanted to ask if the UMC has the same warranty as the car? I can not seem to find that information online.
 
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Just to update this thread, I was able to get a replacement UMC from Tesla Indianapolis, this solved my charging problems. I wanted to ask how common is a UMC failure, I really hope this replacement one will last the life of my car...
 
I wanted to ask how common is a UMC failure, I really hope this replacement one will last the life of my car...
I have seen several reports here on the forums of bad UMCs right out of the gate in the past couple of years. It happens. I do work in the electronics industry, though, and there is this thing called the "bathtub curve", which is a plot of failures over time. It's common that the number of failures right at the start is high, as there were some chips that were borderline defective and very quickly fell over the edge and failed right away when they started getting used with some stress on them. Once those are found and replaced, the number of failures drops down and stays low for quite a long time. And then eventually it climbs back up years later when materials finally age and degrade. So it's just a thing, and that's what early warranties are for. I'm still using my original mobile cable from over 7 years ago.
 
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Another point to consider is that the OP stated that they use the Mobile Connector outdoors where is is exposed to the elements. The Tesla Gen2 Mobile Connector user manual states on Page 2:

Warning: Do not use the Mobile Connector when either you, the vehicle or the Mobile Connector is exposed to severe rain, snow, electrical storm or other inclement weather.

Warning: Protect the Mobile Connector from moisture, water and foreign objects at all times.If any exist or appear to have corroded or damaged the Mobile Connector, do not use the Mobile Connector.

Warning: If rain falls during charging, do not allow rain water to run along the length of charge cable, causing the electrical outlet or charging port to become wet.

Warning: Do not plug the Mobile Connector into an electrical outlet that is submerged in water or covered in snow. If, in this situation, the Mobile Connector is already plugged in and needs to be unplugged, turn off the breaker before unplugging the Mobile Connector.
 
Another point to consider is that the OP stated that they use the Mobile Connector outdoors where is is exposed to the elements. The Tesla Gen2 Mobile Connector user manual states on Page 2:

Warning: Do not use the Mobile Connector when either you, the vehicle or the Mobile Connector is exposed to severe rain, snow, electrical storm or other inclement weather.

Warning: Protect the Mobile Connector from moisture, water and foreign objects at all times.If any exist or appear to have corroded or damaged the Mobile Connector, do not use the Mobile Connector.

Warning: If rain falls during charging, do not allow rain water to run along the length of charge cable, causing the electrical outlet or charging port to become wet.

Warning: Do not plug the Mobile Connector into an electrical outlet that is submerged in water or covered in snow. If, in this situation, the Mobile Connector is already plugged in and needs to be unplugged, turn off the breaker before unplugging the Mobile Connector.
This is where I do not like Tesla wordings at all. Tesla states this in a manual, however, when I spoke with the service tech in-person, I ask him if I can use the UMC outside, in the rain, direct sunlight, etc. He not only said yes with confidence but also said, they are able to handle the rain, sun, cable stresses, etc.... I have been a lot more delicate with this new UMC because knowing my luck, I will have one that breaks as soon as my warranty ends...
 
My UMC has started to experience intermittent failures also. Unfortunately, although I have only 16K miles on the car, it is five years old, so outside the warranty (which is 50K miles or 4 years, whichever comes first). If it is a degrading chip, I would expect it to fail permanently, not intermittently. The first couple times I was able to get it charging again by pressing the reset button on the back of the mobile connector chassis. However, one day it wasn't charging and nothing worked--I tried plugging it into a 110V outlet, into a 220V outlet, rebooting the computer (pressing both scroll wheels simultaneously), nothing worked. I borrowed a neighbor's UMC and it worked fine. Conclusion, my UMC is failing. The next day, I tried mine again, and once again it was working. Tesla mobile tech came out (10 days later....), but brought wrong part. Now I need to wait another two weeks to get a replacement part. Tesla is very short staffed! They better get their act together re service, or they will start losing customers (if they haven't already). I'm asking Tesla to do a goodwill warranty replacement, as my car only has 16k miles, and I charge indoors, so no rain or weather issues. Waiting to hear back from them re free replacement. New mobile connector on website costs $520--and they're out of stock! I don't trust any of the charging cables I see on Amazon, as none are UL listed. I don't need the whole setup (like a JuiceBox), as I already have the 220V outlet installed.
 
My UMC has started to experience intermittent failures also. Unfortunately, although I have only 16K miles on the car, it is five years old, so outside the warranty (which is 50K miles or 4 years, whichever comes first). If it is a degrading chip, I would expect it to fail permanently, not intermittently. The first couple times I was able to get it charging again by pressing the reset button on the back of the mobile connector chassis. However, one day it wasn't charging and nothing worked--I tried plugging it into a 110V outlet, into a 220V outlet, rebooting the computer (pressing both scroll wheels simultaneously), nothing worked. I borrowed a neighbor's UMC and it worked fine. Conclusion, my UMC is failing. The next day, I tried mine again, and once again it was working. Tesla mobile tech came out (10 days later....), but brought wrong part. Now I need to wait another two weeks to get a replacement part. Tesla is very short staffed! They better get their act together re service, or they will start losing customers (if they haven't already). I'm asking Tesla to do a goodwill warranty replacement, as my car only has 16k miles, and I charge indoors, so no rain or weather issues. Waiting to hear back from them re free replacement. New mobile connector on website costs $520--and they're out of stock! I don't trust any of the charging cables I see on Amazon, as none are UL listed. I don't need the whole setup (like a JuiceBox), as I already have the 220V outlet installed.
The Gen2 Mobile Connector Bundle is currently in stock, available on the Tesla site for $275. You would also need to purchase the NEMA 14-50 plug adapter separately for $45 from the Tesla store. If you want the Corded Mobile Connector (capable of supporting charging at up to 40 amps versus 32 amps for the Gen2 Mobile Connector), it is currently out of stock on the Tesla site; you should be able to find it on eBay.

When you use your current Mobile Connector do you let the Mobile Connector hang supported by the power plug cord? Over time the power plug cord can stretch and fail. Tesla sells a Cable Organizer that includes a wall mount for the Mobile Connector chassis. You can find similar organizer kits on Amazon, also fashion your own hanger for the Mobile Connector chassis.
 
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