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UMC Error

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So I've had my CPO Roadster for just over 2 weeks. It was supposed to come with a UMC, but I've been told they're backordered until late September. So, I grabbed on off eBay, but I sadly think I got a bum unit.

I'm tried the UMC on a 240V L6-50 outlet, which has been successfully charging the Roadster with a 30 amp Blink EVSE with a J1772 adapter. I know the outlet is good. When I plugin the UMC, the green light just blinks repeatedly. It never goes solid. I plug it into the Roadster charging port, which is lit white, and nothing happens. When I press the reset button, the fault light comes on, and then goes out when I release the reset button and the flashing green light continues.

I read the manual, but it makes no mention of a flashing green light.

Anyone have any ideas?
 
I know the UMC can be finicky with grounding. Also make sure the rubber gasket is in place at the charge port connector part of the UMC where it mates to the connector on the Roadster... heard if that's missing the UMC will throw errors. Before drawing any conclusions that the UMC is bad I'd find another Tesla owner close by or stop by Tesla to test it out. Key here is find a place where an existing UMC works and try yours, then you can be sure if its bad grounding at your house or a bad UMC.

There are some threads in the forum that discuss more on the grounding issues with the UMC. Mine worked fine... was an ebay purchase. Plus my house is from the 50's so I thought for sure it'd complain.
 
Well, I tried 3 different outlets - still not working. Two of the outlets are currently successfully charging my other two plugin cars via Blink EVSE's. The other was installed by an licensed electrician so I'm confident in the outlets.

What confuses me is that I"m not getting a fault message on the UMC. I'll post a link below to a 10 second video in case anyone has any ideas:

Dropbox - Roadster UMC.MOV