Heated Oxygen Sensor (Ho2S)

With engine at room temperature, disconnect HO2S connector. Measure resistance across terminals "C" and "D". See Fig 1 . See HO2S RESISTANCE table. Replace HO2S as necessary. Also se PIN VOLTAGE CHARTS article in the ENGINE PERFORMANCE section.

Fig 1: Testing HO2S (929)

Courtesy of MAZDA MOTORS CORP.