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Home >> Kia >> 2005 >> Optima EX, 2.4 6 >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control System/Fuel System - 2.4L (A/T) >> MFI Control System >> HEATED OXYGEN SENSOR (HO2S) - ZIRCONIA (ZrO ) >> Inspection >> Using Voltmeter
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Using Voltmeter

NOTE:
  • Before checking, warm up the engine until the engine coolant temperature reaches 80 to 95 °C (176 to 205 °F).
  • Use an accurate digital voltmeter.
  1. Disconnect the Heated Oxygen Sensor (HO2S) connector, and measure the resistance of heater between terminal 3 and terminal 4.

    Specification:

    1. Front HO2S: 5.0-7.0 Ω
    2. Rear HO2S: 5.0-7.0 Ω

  2. Replace the Heated Oxygen Sensor (HO2S) if there is a malfunction.
  3. Apply battery voltage directly between terminal 3 and terminal 4.
    NOTE: Be careful when applying the voltage. Damage will result if terminals 1 and 2 are connected to any voltage.
  4. Connect a high-impedance digital-type voltmeter between terminal 1 and terminal 2.
  5. While repeatedly racing the engine, measure the Heated Oxygen Sensor (HO2S) output voltage.
  6. If there is a problem, replace the Heated Oxygen Sensor (HO2S).

    Tightening torque: 40 - 50 N.m (4.0 - 5.0 kg. m, 29 - 36 lb. ft)