P0B2AHybrid/EV Battery B Voltage High
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P0B2A is stored when the voltage of hybrid/EV battery B rises above its permitted upper limit. It mirrors P0B29 (too low), while P0B28 covers fluctuation and P0B27 the general fault. No manufacturer explains P0B2A publicly; the closest documented case is Bentley's P0B26 for battery A, where a failing 48 V super capacitor reads too high. GM's analogous whole-pack overvoltage monitor is P0ABD (above 479 V, Type A). CARB demands monitoring of battery voltage sensors and cells in hybrid storage systems. Likely causes are a cell group charged too high because balancing fails, or a measuring fault. To protect the cells the controller restricts charging and recuperation and may open the contactors.
- What you may notice
- Hybrid/EV system or high-voltage battery warning on
- MIL on
- Charging or recuperation restricted
- Battery power limited, less electric drive or assist
- Likely causes
- PossibleCell group in battery B charged too high, balancing ineffective
- PossibleVoltage measurement fault in the controller or sense leads
- RareBattery controller software fault
- 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 – €4,000
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.