P2BC6Battery Charging System Positive Contactor B Stuck Open
- Generic OBD-II code · Powertrain
- How the car detects it
- P2BC6 means positive charging contactor B does not close when commanded, so the plus side of that charging branch stays dead and the session aborts or never starts. The only maker documenting it publicly is Mazda: on the 2024–2026 CX-90 and 2025–2026 CX-70 plug-in hybrids it reads OBC contactor (+) stuck off, listed with the welded cases P2BC5 and P2BCC. Mazda traces all three to a contact-welding problem in these contactors and fits a new Junction Box No. 2 (bulletin 30-003-26). GM's analogous test for contactor A on the Chevrolet Volt (P0D09) shows the principle: during precharge the voltage on the charger side must build up, and a reading under 10 V ends the check as failed. Welding is P2BC5, the negative side P2BCD. Driving normally continues.
- What you may notice
- Charging session stops or does not start
- Hybrid system malfunction message (Mazda)
- Driving usually unaffected
- Likely causes
- LikelyContactor B damaged inside and no longer closing (Mazda junction box)
- PossibleCoil supply or drive line interrupted
- RareCharging control software misjudging the closing 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.