Hybrid/EV Battery Internal Isolation Performance
The BMS detects degraded internal isolation between HV bus and battery enclosure. Insulation resistance below safety threshold.
Affected components
- Hv battery pack
- Bms
- Isolation monitor
Common causes
- High likelihood: Internal cell insulation aged
- Medium likelihood: Internal moisture
- Low likelihood: Pack cell imbalance approaching service threshold
Possible symptoms
- EV/hybrid system warning light on
- Reduced power output or limp mode
- Charging may fail or be slowed
- Reduced electric range
Diagnostic notes
- The malfunction indicator lamp may illuminate
- Reduced-power or limp mode may occur
Sources
Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.