P2248O2 Sensor Reference Voltage Performance (Bank 2 Sensor 1)
- 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
- P2248 is meant for a reference voltage signal on the bank 2 upstream wide-band sensor that is present but implausible, as opposed to an open or shorted line. No manufacturer documents P2248 publicly, and the published diagnostic tables of Ford, GM, Saab and VW cover the bank 2 Nernst-cell line only with the open-circuit code P2247, while Ford routes shorts to P0151/P0152. A drifting reading usually stems from an aged or poisoned sensor element or extra resistance in the circuit, which Bosch's 300-ohm nominal cell value makes measurable. CARB requires upstream sensors to be monitored for out-of-range and implausible output. P2244 is the bank 1 counterpart, P2247 the open line, P2249/P2250 low/high. Mixture control on bank 2 becomes less accurate.
- What you may notice
- Check engine light
- Slightly higher fuel consumption
- Possible failed emissions test
- Likely causes
- LikelyAged or contaminated wide-band sensor on bank 2
- PossibleHigh resistance in the reference voltage wire or connector
- RareExhaust leak ahead of the bank 2 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: €80 – €400
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.