Sensor Output Value Inspection (HO2S)

WARNING: This page is about a different car, the 2009 Mazda 6. However, it is still accessible from the selected car via links, so may be relevant.

Perform the inspection according to the following procedure using the PID/DATA monitor function. See DIAGNOSTIC MONITORING TEST RESULTS [MZI-3.7] .
1. Start the engine and warm it up.
2. Drive the vehicle.
3. Release the accelerator pedal while the engine speed is at 3,000 rpm and verify that the following monitor items fluctuate as shown in the figure while the vehicle decelerates.
  - VSS
  - RPM
  - O2S12, O2S22
    
    Fig 1: PID/DATA Monitor Chart
    Courtesy of MAZDA MOTORS CORP.
4. If not within the specification, replace the HO2S. See HEATED OXYGEN SENSOR (HO2S) REMOVAL/INSTALLATION [MZI-3.7] .