OBD-II code · Powertrain (generic, extended)
P2245 O2 Sensor Reference Voltage Circuit Low (Bank 1 Sensor 1)
The reference voltage feeding the bank 1, sensor 1 wide-band oxygen sensor is below the lower threshold. Often a short to ground in the wiring or a failed reference output stage.
Is it safe to drive with P2245?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyReference line shorted to ground
- Less likelyECU reference output failed
- Less likelyConnector pins corroded - high contact resistance
Symptoms
- Check engine light on
- Increased fuel consumption
- Possible rough idle or hesitation
- Failed emissions test
Repair at a glance
- Difficulty
- Medium
- DIY friendly
- Often, with basic tools
- Typical labour
- 0.5–2 h
- Emissions test
- Likely to fail
- After the fix
- A drive cycle is needed before the light stays off
- Parts involved
- Oxygen Sensor Upstream, Oxygen Sensor Wiring
Related codes
- P2244O2 Sensor Reference Voltage Circuit Range/Performance (Bank 1 Sensor 1)
- P2246O2 Sensor Reference Voltage Circuit High (Bank 1 Sensor 1)
- P2249O2 Sensor Reference Voltage Circuit Low (Bank 2 Sensor 1)
- P22B0O2 Sensor Reference Voltage Circuit Low (Bank 1 Sensor 2)
- P22BDO2 Sensor Reference Voltage Circuit Low (Bank 2 Sensor 2)
- P2242O2 Sensor Pumping Current Circuit High (Bank 2 Sensor 1)
- P2243O2 Sensor Reference Voltage Circuit (Bank 1 Sensor 1)
- P2247O2 Sensor Reference Voltage Circuit (Bank 2 Sensor 1)
- P2248O2 Sensor Reference Voltage Circuit Range/Performance (Bank 2 Sensor 1)
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.