EPAS3S family
EPAS3S_a078_phaseDisconnectError
Not Available
What does the EPAS3S_a078_phaseDisconnectError alert mean?
Phase disconnect FET startup check error
What you'll see in your Tesla
- Not Available
What triggers it
Phase disconnect FET startup check error
When it clears
Clear fault and power cycle
Potential impact
Reduced steering assist
Affected models
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.