P2245 code meaning
O2 Sensor Reference Voltage Circuit Low (Bank 1 Sensor 1)
Powertrain system Generic code P22xx codes Check engine light
What P2245 means
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.
P2245 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyMedium, DIY possible
- Typical labor0.5 to 2 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P2245
- Check engine light
- Higher fuel consumption from open-loop fuelling on bank 1
- Uneven idle or hesitation in some cases
Common causes of P2245
- Most likelyReference voltage wire shorted to ground (chafed against exhaust or body)
- PossibleSensor element damaged internally, for example by water hitting the hot ceramic
- Less likelyFault in the sensor interface of the ECM
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Oxygen sensor bank1 sensor1Oxygen sensor wiringECM
What each part of P2245 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 2 | Area: fuel and air metering (injector circuit). |
| 45 | The exact fault in that area. |
What to do next
- Note P2245 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P2245
What does P2245 mean?
P2245 means "O2 Sensor Reference Voltage Circuit Low (Bank 1 Sensor 1)". 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. It is a generic code, so it means the same on every make.
Is it safe to drive with P2245?
Usually yes, for a short time, if the check engine light is steady and the car drives normally. If the light flashes or the car runs badly, stop and have it checked.
Will P2245 fail an emissions test?
Yes, it can. P2245 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P2245 to fix?
Difficulty: medium. A typical repair takes 0.5 to 2 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will P2245 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.