P22B4O2 Sensor Negative Current Control Circuit High (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
- P22B4 is stored when the negative current control line (virtual ground) of the bank 1 downstream wide-band probe climbs above its intended bias. Because this return sits at a mid-level voltage rather than at chassis ground, a short to the heater feed or battery voltage is the classic trigger, sometimes via moisture or a heat-damaged connector. No maker documents this exact code publicly; Mitsubishi lists the upstream analog P2253 as a two-trip code for the 2022 Outlander, while Ford treats upstream shorts to power as P0132. CARB asks for detection of out-of-range values on such sensors. P22B2 is the open, P22B3 the low variant, P22C1 the bank 2 code. The lamp is on and the related emission monitors will not complete.
- What you may notice
- Check engine light
- Downstream oxygen reading erratic or at a limit
- Likely causes
- LikelyReturn wire shorted to heater supply or battery voltage
- PossibleHeat-damaged or wet connector bridging pins
- PossibleInternal heater-to-cell leakage in the sensor
- 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.