P0B30Hybrid/EV Battery D Voltage Unstable
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P0B30 reports an unstable voltage of hybrid/EV battery D: the measured value fluctuates beyond the limit the controller allows. It differs from P0B31 and P0B32, which stand for a lasting low or high voltage, and from the general fault P0B2F. No manufacturer documents P0B30 publicly. The sibling codes for batteries A and B show the typical background: Stellantis and Ford corrected P0B24 and P0B28 by updating the battery controller software, and Jeep even blocks starting after 49 days with P0B28. CARB requires the hybrid storage voltage sensors to be monitored. Apart from software, poor contact at busbars or sense terminals and cells with high internal resistance make the reading of unit D jump.
- What you may notice
- Hybrid/EV system or high-voltage battery warning on
- MIL on
- Warning comes and goes, fault often stored as intermittent
- Battery power limited, less electric drive or assist
- Likely causes
- PossibleLoose busbar, terminal or sense contact in battery D
- PossibleBattery controller software (pattern known from P0B24/P0B28)
- RareCell with rising internal resistance in battery D
- 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: €80 – €3,000
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.