UI family
UI_a157_MCUActiveCoolingRequested
Not Available
What does the UI_a157_MCUActiveCoolingRequested alert mean?
MCU requires colder coolant to maintain functionality
What you'll see in your Tesla
- Not Available
What triggers it
MCU temperature exceeds nominal operating temperature
When it clears
MCU has cooled down sufficiently and Supercharge drive and charge session completed
Potential impact
Reduced supercharging/HVAC performance and additional noise and vibrations
Affected models
Cybertruck
Model 3 2017-2023
Model 3 2024+
Model S 2021+
Model X 2021+
Model Y
Model Y 2025+
Track your Tesla's alerts automatically
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.