P2BC5Battery Charging System Positive Contactor B Stuck Closed
- Generic OBD-II code · Powertrain
- Can trigger limp mode
- How the car detects it
- P2BC5 reports that positive charging contactor B still conducts after the open command, normally because its contacts have fused. Mercedes-Benz stores it, often with P2BCC, in the DC charge connection unit (N116/5, on the eSprinter N24/6) of GLE, E- and S-Class plug-in hybrids, the EQB and the eSprinter; after a DC session the vehicle refuses to start. Bulletin LI47.70-P-079912 blames current ripple, overcurrent or overvoltage from the station and contacts that part too late, and prescribes a software update plus a contactor-fault reset rather than a new unit. Mazda lists it as OBC contactor (+) stuck on in CX-90 (from 2024) and CX-70 (from 2025) plug-in hybrids and swaps Junction Box No. 2 (30-003-26). The reverse fault is P2BC6, the minus side P2BCC.
- What you may notice
- Vehicle will not start after DC charging (Mercedes)
- High-voltage or hybrid system warning in the cluster
- Further charging blocked
- Likely causes
- LikelyContacts of positive contactor B welded, e.g. after current peaks at the end of charging
- PossibleSoftware of the charging module judges the contactor state wrongly (Mercedes update)
- PossibleRipple, overcurrent or overvoltage from the charging station
- RareCoil driver does not switch off
- 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.