P2245O2 Sensor Reference Voltage Circuit Low (Bank 1 Sensor 1)
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- P2245 reports that the reference voltage side of the upstream air-fuel sensor on bank 1 reads too low, usually because the wire touches ground or the sensor has shorted internally. GM's tables for the Saturn Vue 3.5 V6 (L66, 2004-05) define it precisely: with the engine running for over 85 s, the heater active and the element signal between 3.2 and 4.6 V, a pump-cell circuit voltage below 1.5 V for 0.5 s stores the code in the first drive cycle. Jaguar Land Rover lists P2245 among the front-sensor codes in bulletin LTB00671 (2014-16 3.0 supercharged V6), where water caused thermal shock and the sensor is renewed. GM's 2018 Duramax table 18OBDG04 counts it among faults that invalidate the front sensor signal. P2243 is the open line, P2246 high, P2249 bank 2.
- What you may notice
- Check engine light
- Higher fuel consumption from open-loop fuelling on bank 1
- Uneven idle or hesitation in some cases
- Likely causes
- LikelyReference voltage wire shorted to ground (chafed against exhaust or body)
- PossibleSensor element damaged internally, for example by water hitting the hot ceramic
- RareFault in the sensor interface of the ECM
- 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 – €450
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.