P22B3O2 Sensor Negative Current Control Circuit Low (Bank 1 Sensor 2)
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Needs a drive cycle to confirm a fix
- How the car detects it
- P22B3 reports the negative current control line, i.e. the virtual ground of the bank 1 downstream wide-band probe, as too low. Normally the controller lifts this common return to a bias near 2.5 V (Saab measures that at the plug of its 2010 9-5) so that pump current can flow in both directions; a short to chassis ground collapses the bias and with it the measuring range. No maker documents this exact code publicly. Mitsubishi lists the upstream analog P2252 as a two-trip code for the 2022 Outlander, and Ford handles upstream shorts under P0131 instead. P22B2 is the open-circuit code, P22B4 the high one, P22C0 the bank 2 version. Apart from the warning lamp, the driver rarely notices anything.
- What you may notice
- Check engine light
- Downstream oxygen value implausible or pinned
- Likely causes
- LikelyReturn wire shorted to chassis ground through chafed insulation
- PossibleInternal short inside the wide-band sensor
- RareFaulty bias supply in the ECM or sensor module
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Often possible to do yourself.Typical cost: €50 – €450
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.