P0C30Hybrid/EV Battery Pack State of Charge High
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- Needs a drive cycle to confirm a fix
- How the car detects it
- P0C30 is the counterpart of P0A7D: the battery controller finds that the state of charge of the high-voltage pack stays above its usable window. CARB requires hybrid OBD to flag a state of charge that can no longer be kept inside the manufacturer's range. GM's 2019 hybrid table 19OBDG01 describes the method: the SOC is checked once per drive cycle, the controller first allows time for the motor to draw the charge back down, then counts the distance driven with excessive SOC; if that share exceeds half of a trip longer than 50 km, at speeds above 15 km/h and pack temperature at least −10 °C, the code is stored as Type B, two trips. No other manufacturer documents it publicly. The car limits regeneration and charging to protect the cells, so braking feel and fuel economy can change.
- What you may notice
- MIL after two trips
- Reduced or no regenerative braking
- Changed brake pedal feel and higher fuel consumption
- Likely causes
- PossibleWrong SOC estimate from a drifting pack current or voltage measurement
- PossibleBattery or hybrid control software not drawing the charge down as intended
- RareElectric assist blocked by another fault, so the pack cannot discharge
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Workshop only · Usually a job for a workshop.Typical cost: €100 – €2,000
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.