P0C75Hybrid/EV Battery System Discharge Time Too Short
- 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
- P0C75 is logged when the high-voltage bus loses its voltage faster than expected after the contactors open. At shutdown the inverter's DC-link capacitor is drained through a discharge resistor or an active discharge circuit, and from capacitance and resistance the controller knows roughly how long that should take. A much quicker drop points to lost capacitance, a lower resistance than designed, a leakage path or a wrong voltage reading. A capacitor diagnostic patent (EP2682769B1) uses the same comparison to detect capacitor ageing. No manufacturer documents P0C75 publicly; GM publishes only the opposite check, P0C76. The driver usually sees a hybrid warning lamp, and depending on the make the next start may be blocked.
- What you may notice
- Hybrid or EV system warning lamp
- Vehicle may not become ready to drive
- Likely causes
- PossibleDC-link capacitor lost capacitance through ageing or damage
- PossibleAdditional load or leakage path on the high-voltage bus
- PossibleBus voltage measured incorrectly by the inverter or battery module
- RareDischarge resistor or circuit with too low a resistance
- 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 – €2,500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.