IBST family
IBST_a001_microSupplyError
Power braking assist reduced
What does the IBST_a001_microSupplyError alert mean?
iBooster (IBST) voltage monitor has detected a failure of the microcontroller supply voltage. Condition is an electronic control unit (ECU) internal error.
What you'll see in your Tesla
- Power braking assist reduced
- Braking may require increased effort
What triggers it
Voltage monitor detects a failure of the microcontroller supply voltage.
When it clears
iBooster can not recover from this condition. iBooster replacement may be required.
Potential impact
IBST may not operate as expected.
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.