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Home >> Kia >> 2018 >> Optima EX >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control System Diagnosis - 2.4L (1 Of 3) (Except HEV) >> DTC P0140-00: O2 Sensor Circuit No Activity Detected (Bank 1/Sensor 2) >> Wiring Inspection >> Signal Circuit Inspection
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Signal Circuit Inspection

  1. Ignition "OFF".
  2. Refer to HEATED OXYGEN SENSOR (HO2S) and disconnect Downstream O2 Sensor connector.
  3. Ignition "ON".
  4. Measure voltage between Pin No. 1 (Signal) terminal of Downstream O2 Sensor harness connector and chassis ground.

    Specification  : Approx. 0.5 V

  5. Is the measured value within specification?

    YES 

    NO