P0C30 code meaning
Hybrid/EV Battery Pack State of Charge High
Powertrain system Generic code P0Cxx codes Check engine light
What P0C30 means
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.
P0C30 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyWorkshop only
- Typical labor1 to 5 hours
- Clears after repairAfter a drive cycle
Symptoms of P0C30
- MIL after two trips
- Reduced or no regenerative braking
- Changed brake pedal feel and higher fuel consumption
Common causes of P0C30
- PossibleWrong SOC estimate from a drifting pack current or voltage measurement
- PossibleBattery or hybrid control software not drawing the charge down as intended
- Less likelyElectric assist blocked by another fault, so the pack cannot discharge
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Hv battery packBms
What each part of P0C30 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| C | Area: hybrid propulsion. |
| 30 | The exact fault in that area. |
What to do next
- Note P0C30 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P0C30
What does P0C30 mean?
P0C30 means "Hybrid/EV Battery Pack State of Charge High". 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. It is a generic code, so it means the same on every make.
Is it safe to drive with P0C30?
Drive gently and only to a workshop. With P0C30 the car can go into limp mode (reduced power) to protect itself.
Will P0C30 fail an emissions test?
Yes, it can. P0C30 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P0C30 to fix?
Difficulty: workshop only. A typical repair takes 1 to 5 hours of work. This is a job for a workshop.
Will P0C30 clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.