P0BB3Hybrid/EV Battery Voltage Sense Y Circuit
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P0BB3 reports that the sense lead of channel Y, the twenty-fifth cell group, is no longer properly connected. GM's 16OBDG02 programme does not wait for odd voltages but calculates the resistance of the sense line and fails it above 30.00 in seven of nine samples, which is a one-trip Type A fault; the unit is missing in the table. The 2019 battery energy control module instead looks at the cell voltages themselves, for example 1.3 V between neighbours or a reading below 36 mV while that cell is being balanced, with 0.8 s of failure in 1.6 s. The eAssist mild hybrid sets it as a Type B fault when lines N and N-1 both read under 1.4 V and jump by more than 0.5 V. Low and high monitors for Y are blocked while P0BB3 is active.
- What you may notice
- MIL and high-voltage system warning
- Vehicle may not start in electric mode
- Charging aborted
- Likely causes
- LikelyOpen circuit in sense lead Y
- PossibleCorroded or loose terminal raising line resistance at Y
- RareCell monitoring slave board fault on input Y
- 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: €150 – €7,000
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.