Powertrain
generic / SAE
P0CA4
Hybrid/EV Battery Charging Voltage High
The HV battery charging voltage exceeds the safe upper limit. Risk of cell damage from overvoltage. Cell-group voltage monitoring is the foundation of HV battery safety — drift here triggers contactor opening, charge inhibit, and reduced power to protect the pack.
SystemPowertrain
Typegeneric / SAE
GroupP0
Range / numberC / A4
Possible causes
- Charger regulation off high
- BMS disagrees with charger setpoint medium
- Pack cell imbalance approaching service threshold low
Symptoms
- EV/hybrid system warning light on
- Reduced power output or limp mode
- Charging may fail or be slowed
- Reduced electric range
Inspection / repair
- Difficulty: hard
- DIY: shop recommended
- Estimated cost: 500–4000 €
- Estimated time: 3–14 h
- Component: hv battery
- Component: bms
- MIL / check engine light
- limp mode possible
Sources
References
sae:J2012