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Home >> Kia >> 2016 >> Forte LX, Automatic Trans >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control System Diagnosis - 1.8L (1 Of 3) >> DTC P0139: O2 Sensor Circuit Slow Response (Bank 1/Sensor 2) >> System Inspection >> Visual/Physical Inspection
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Visual/Physical Inspection

  1. Visually/physically inspect the following conditions:
    • Check for corrosion on terminals
    • Check for terminal tension (at the HO2S and at the PCM/ECM)
    • Check for damaged wiring
    • Check the HO2S ground circuit for a good connection
    • Check front and rear HO2S for connections being reversed
  2. Was a problem found in any of the above areas?

    YES 

    NO 

    • Go to next step as below.