UMC family
UMC_a005_inputUnderVoltage
Unable to charge with Mobile Connector
What does the UMC_a005_inputUnderVoltage alert mean?
UMC AC input voltage is below lower limit
What you'll see in your Tesla
- Unable to charge with Mobile Connector
- Voltage too low / Try a different wall outlet
What triggers it
UMC AC input voltage has fallen below 90 V RMS
When it clears
UMC input voltage has risen above 90 V RMS
Potential impact
UMC will not allow charging until AC input voltage is within 90-300 V RMS
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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