IBST family
IBST_a085_supplyUndervoltageLvl3
Power braking assist reduced
What does the IBST_a085_supplyUndervoltageLvl3 alert mean?
iBooster (IBST) detected UBB supply voltage is below shutdown threshold (undervoltage level 3).
What you'll see in your Tesla
- Power braking assist reduced
- Braking may require increased effort
What triggers it
IBST detected UBB supply voltage is below shutdown threshold.
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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