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Home >> Mazda >> 2004 >> 3 i, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System >> Front Heated Oxygen Sensor (Ho2S) Inspection >> Front HO2S current inspection
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Front HO2S current inspection

  1. Warm up the engine to normal operating temperature.
  2. Using the WDS or equivalent, monitor the following:
    • Vehicle speed (PID: VSS)
    • Engine speed (PID: RPM)
    • Front HO2S Current (PID: O2S11)
  3. Drive the vehicle and decelerate the engine speed by releasing the accelerator pedal fully when the engine speed is 3,000 rpm or more. 
  4. Verify that the front HO2S current (PID: O2S11) is 0.25 mA or more  while decelerating as shown in the figure.
    Fig 1: Front HO2S Current Graph While Decelerating-California Emission Regulation Applicable Model
    G00972632Courtesy of MAZDA MOTORS CORP.