Mobile Charger Issue - Red Blinking light

[mongo]

Bad grounding would result in no charging, not slow charging.

 

[pae1andonly]

Yup, same exact issue. Can you come back and post results here so I have a better idea of what to do?

This is killing me on my road trip out in the country. I can’t plug in overnight and keep losing charge. Probably 4% each night even though I have turned off everything I can think of.

Will do. Appt on Tuesday.

 

[pae1andonly]

Mine did the same thing I turned off the breaker let it cool down for a while turned it back on. It worked fine.

I turned off the breaker for a week ... no change.

 

[pae1andonly]

TSC said they are having a lot of problems with UMC Version (Gen?) 3.

 

[shopaholic]

It’s intermittent, never had this happen charging the 3 for years!

 

[Derektsla]

TSC said they are having a lot of problems with UMC Version (Gen?) 3.

Thanks! I’ll get a ticket in to get this fixed.

 

[anurag0888]

TSC said they are having a lot of problems with UMC Version (Gen?) 3.

Any luck with this ? Tesla service looked at this issue and replaced my UMC. Still no luck charging CT but charges model y just fine.

 

[pae1andonly]

Any luck with this ? Tesla service looked at this issue and replaced my UMC. Still no luck charging CT but charges model y just fine.

Since the Service Center replaced the mobile charger, it has worked quite well on a 50 amp 240 volt circuit NEMA 14 50 plug charging at @20mph 32 amps.

It is possible this originated from the UMC being in direct July sunlight and over-heating. It never worked correctly after that. Going with black for the charger handle (the only part that was outside) seems a questionable choice.

 

[DuaneSql]

Since Cybertruck operating system update 2025.32.0, I have had charging problems. I took it to the dealer and they replaced my mobile charger, but I am still having problems. The charging problems improved a little when I updated to 2025.32.6.

It won't remember to default to 9Amps, I have to watch it default to 48 Amps and manually turn it down in the app to 9 Amps everytime. This problem started with 2025.32.0

 

[mongo]

Since Cybertruck operating system update 2025.32.0, I have had charging problems. I took it to the dealer and they replaced my mobile charger, but I am still having problems. The charging problems improved a little when I updated to 2025.32.6.

It won't remember to default to 9Amps, I have to watch it default to 48 Amps and manually turn it down in the app to 9 Amps everytime. This problem started with 2025.32.0

The 9 amps is controlled on the truck side, not the mobile connector. Should be location based (unless it also pulls a connector ID)