P0144 O2 Sensor Circuit High Voltage Bank 1 Sensor 3

P0144 indicates high voltage on the bank 1 sensor 3 oxygen sensor circuit. The downstream signal is stuck high 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 assume a rich mixture caused the high voltage until sensor wiring and ground integrity are verified.

Symptoms of P0144

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 P0144

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 bank 1 sensor 3 signal voltage, ground path, open circuits, short-to-voltage faults, heater operation, and connector fit.
Inspect sensor contamination, rich-running conditions, exhaust leaks, wiring near exhaust heat, and shared ground or reference issues.
Compare high voltage behavior with upstream oxygen sensor data, fuel trims, catalyst monitor status, and freeze-frame load.

Related OBD-II codes

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