P2BC8Battery Charging System Positive Contactor B Control Circuit Range/Performance
- Generic OBD-II code · Powertrain
- How the car detects it
- P2BC8 flags a control circuit of positive charging contactor B that is connected but behaves implausibly: the coil draws a current that does not fit the command, the line voltage lies in an unexpected band, or pulling in takes too long. No manufacturer documents P2BC8 publicly. CARB demands rationality checks in addition to circuit checks for the charging components of plug-in vehicles. A GM patent explains one way to judge a coil: send a short pulse, record the current response and compare it with stored values, which reveals a winding or armature that no longer behaves as designed. Likely culprits are corrosion at the pins, a coil with drifting resistance and an ageing output stage. Opens are P2BC7, hard low or high readings P2BC9/P2BCA, the contactor A equivalent P0D0B. Charging may work only intermittently.
- What you may notice
- Charging works only now and then
- Charging aborts with a fault message
- Likely causes
- LikelyContact resistance at connectors of the control line
- PossibleCoil resistance of contactor B outside specification
- RareDriver stage in the module degraded
- Repair
- Workshop only · Usually a job for a workshop.Typical cost: €100 – €1,500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.