SCS family
SCS_a027_externalIsolationLow
Not Available
What does the SCS_a027_externalIsolationLow alert mean?
Supercharger detected a low isolation measurement while connected to the vehicle.
What you'll see in your Tesla
- Not Available
What triggers it
Supercharger isolation measurement result was less than the fault threshold.
When it clears
Supercharger isolation measurement result is greater than the fault threshold.
Potential impact
May cause breakdown of isolation on the Supercharger or vehicle High Voltage (HV) link.
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.