Home >> Subaru >> 2021 >> WRX Base >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control System (Diagnostics) (2.0L) (1 Of 4) >> Diagnostic Procedure with Diagnostic Trouble Code (DTC) >> DTC P0031: A/F/02 Heater Control Circuit Low Bank 1 Sensor 1 >> Execution Condition