P0044 HO2S Heater Control Circuit High Bank 1 Sensor 3

P0044 indicates a high heater control circuit for bank 1 sensor 3. The heater path is open, shorted to voltage, or above expected range.

Code details

Generic OBD-II · P0

System: Fuel / Air
Code type: Generic (SAE / ISO controlled)
Standard: SAE J2012 / ISO 15031-6

Diagnostic boundary

A diagnostic trouble code reports that a monitored test failed. It does not prove one specific part is bad, and manufacturer logic can add vehicle-specific conditions.

Do not replace upstream sensors for a bank 1 sensor 3 heater high code; confirm the exact downstream sensor circuit.

Symptoms of P0044

Check-engine light on, sometimes with rough or uneven running.
Hesitation, surging, or a noticeable change in fuel economy.
Occasionally hard starting or a smell of unburnt fuel.

Common causes of P0044

A failing or contaminated sensor (MAF, MAP, oxygen or air-fuel sensor).
Intake or vacuum leaks, or an exhaust leak near an upstream sensor.
Wiring, connector, or fuel-delivery problems that skew the reading.

Useful checks before replacing parts

Check heater signal voltage, feed supply, ground path, open circuits, short-to-voltage faults, connector fit, and sensor heater resistance.
Inspect exhaust-side harness routing, melted insulation, loose terminals, sensor connector corrosion, and shared heater circuit faults.
Verify sensor location and bank identification before replacing bank 1 sensor 3 or repairing the heater wiring.

Related OBD-II codes

These nearby fuel / air entries can help compare wording and pin down the fault area.