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Home >> Kia >> 2019 >> Optima EX >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control System Diagnosis (5 Of 6) (HEV) >> DTC P2251-00: O2 Sensor Reference Ground Circuit/Open (Bank 1 Sensor 1) >> System Inspection >> Visual Inspection
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Visual Inspection

  1. Refer to HO2S REMOVAL and visually and/or physically inspect following conditions;
    • Proper installation of O2 Sensors.
    • Check for corrosion on terminals.
    • Check for damaged wiring.
    • Fuel, Engine coolant or oil contamination.
    • Check for good ground for O2 sensor.
  2. Has any problems been found?

    YES 

    NO