DI family
DI_a021_packOvervoltage
Not Available
What does the DI_a021_packOvervoltage alert mean?
The drive interface (DI) electronic control unit (ECU) detects that the high voltage (HV) battery pack is over voltage enough to temporarily disable regenerative braking.
What you'll see in your Tesla
- Not Available
What triggers it
The DI ECU detects that the HV battery pack voltage is significantly over the max bus voltage while the vehicle is in Drive or Reverse.
When it clears
Clears on the next drive cycle.
Potential impact
The DI ECU may disable regenerative braking.
Affected models
Cybertruck
Model 3 2017-2023
Model 3 2024+
Model S 2021+
Model X 2021+
Model Y
Model Y 2025+
Semitruck
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