P1271 NISSAN Air Fuel Ratio Sensor 1 Circuit No Activity Detected Bank 1

Possible causes – Faulty air fuel ratio (A/F) sensor 1 heater Bank 1 – Air fuel ratio (A/F) harness is open or shorted– Air fuel ratio (A/F) circuit poor electrical connection When is the obd code mean? The A/F signal computed by ECM from the A/F sensor 1 signal is constantly approx. 0V. Symptoms –…