P0161 MAZDA HO2S22 Heater Circuit Fault

Possible causes – Faulty Rear Heated Oxygen Sensor Bank 2– Rear Heated Oxygen Sensor Bank 2 harness is open or shorted– Rear Heated Oxygen Sensor Bank 2 circuit poor electrical connection– Inappropriate fuel pressure – Faulty fuel injectors– Intake air leaks– Exhaust gas leaks Tech description Replacing the Rear Heated Oxygen Sensor Bank 2 usually…