P0B65Hybrid/EV Battery Voltage Sense I Circuit Low
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- The 2012 GM two-mode hybrids show a detail worth knowing for P0B65: their battery pack control module only declares channel I, nickel-metal hydride block 9, too low when block 9 and its neighbour block 10 both read under 2 V, and only after 15 of 20 samples at 100 ms; the fault is Type B and needs two trips. A single weak block alone therefore does not set it. GM's lithium-ion controllers judge each cell on its own, setting P0B65 at 0.2 V or less held for 1.4 s within 2 s, Type A, as long as no open-line or communication fault has priority. The BAS Plus mild hybrid uses 1.4 V and 7 of 10 samples. In all cases the reading is too low to be a real cell.
- What you may notice
- Hybrid system warning and MIL
- Engine runs more often, electric assist reduced
- Limited power in limp mode
- Likely causes
- LikelyChannel I sense lead shorted to ground or a lower tap
- PossibleConnector fault affecting adjacent blocks 9 and 10 (two-mode)
- RareFailed measuring input in the battery controller
- 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 – €6,000
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.