BMS family
BMS_a056_SW_Standby_Supply_Fault
Not Available
What does the BMS_a056_SW_Standby_Supply_Fault alert mean?
The Battery Management System (BMS) detects an unexpected condition with its internal low voltage supply inputs.
What you'll see in your Tesla
- Not Available
What triggers it
The output voltage of the standby power supply is outside of the expected bounds.
When it clears
The output voltage of the standby power supply is within the expected bounds.
Potential impact
The standby power supply is unable to power Electronic Control Units (ECUs) during sleep which leads to greater support from the Low Voltage (LV) battery.
Affected models
Model 3 2017-2023
Model 3 2024+
Model S 2021+
Model X 2021+
Model Y
Model Y 2025+
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