UMC family
UMC_a001_gndMonIntrptLineSide
Unable to charge with Mobile Connector
What does the UMC_a001_gndMonIntrptLineSide alert mean?
UMC AC input side ground impedance exceeded threshold
What you'll see in your Tesla
- Unable to charge with Mobile Connector
- Inadequate outlet grounding - Try a different outlet
What triggers it
UMC AC input side ground impedance is above 1 Mohm
When it clears
UMC AC input side ground impedance has fallen below 1 Mohm for several seconds
Potential impact
UMC will not allow charging until the protective earth connection is corrected
Affected models
Cybertruck
Model 3 2017-2023
Model 3 2024+
Model S 2021+
Model X 2021+
Model Y
Model Y 2025+
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Alerts like this reach MyTeslaMate through your car's Tesla telemetry API. MyTeslaMate logs every alert your Tesla reports and turns it into readable history and real-time notifications — hosted TeslaMate with no server to run.