P0044
HO2S Heater Control Circuit High Bank 1 Sensor 3
Heater control voltage of the bank 1, sensor 3 oxygen sensor is above the expected range — short to power or open ground.
- Check engine light: Yes
- Emissions related: Yes
- Repair difficulty: medium
Common causes
Ordered by how often each turns out to be the cause.
- Heater wiring shorted to batteryCommon
- Connector pins corroded - high contact resistanceLess likely
- Supply wire pinched against B+ sourceLess likely
Parts involved
- Oxygen Sensor B1s3 Heater
- Heater Wiring
P0044 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.