Gen 2 NEMA 14-50 backed down to 8A

[herg]

A mobile service tech replaced this for me today, and I'm back up and charging full speed, but I'm curious as to what happened.

I had been charging using this setup at home, Gen2 MC with 14-50 at 32A, for about 6 months. When I went on vacation, I took the mobile connector with me. There was a 14-50 receptacle where I was staying, but at first, the MC did not light up. I found that the breaker was turned off, so I turned that one. Then, I was getting 5 red blinks on the T, and the current was limited to 8A. This happened even when the not plugged into the car. I assumed there was an issue with the receptacle.

Once I was back home, however, the problem continued. I dug up some info on the MC signaling, and it looked consistent with no adapter information being reported to the MC. It was reporting "Wall plug adapter error", not anything regarding overheating. The 5-15 adapter was recognized correctly, and it was charging at 12A, and the MC does work correctly now with the new 14-50 adapter. It also seems that overheating will usually limit charging to 16A with a 14-50.

The adapter was fully inserted into the MC, so I don't think there was a connection issue. The tech said he had never seen this issue before. Do you guys take any precautions before plugging into an unknown receptacle? From what I read, the detection circuit on the Gen 2 is more complex than just a sense resistor. I wonder if that active communications circuit failed somehow, and if so, the timing of using a different receptacle seems like it would be a big coincidence.

 

[GtiMart]

I know the plug has some minimal circuitry, for example to inform the mobile connector of the maximum amperage with that particular plug. Maybe that failed on yours (your 14-50)?

 

[LoveMY]

I recently had the same problem of T letter in TESLA on the charger blinking 5 times and charging reduced to 8Amp from a regular 32Amp. After visiting a Tesla service center, we found out that the culprit is a loose connection inside the Tesla connector -- the connector with the TESLA lights actually could be unplugged apart, a small half containing the wall plug and a large half containing the main connector and long cable to the car charging port. There are 6-7 pins insde. When the connection is loose -- likely due to my unplugging/plugging the charger from the wall outlet, a "fault" error is generated and the T letter turns orange and blinks. Simply disconnect and reconnect the internal plug would solve the problem.