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Home >> Mazda >> 2012 >> 6 V6-3.7L >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Oxygen Sensor >> Testing and Inspection >> Heated Oxygen Sensor (HO2S) Inspection
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Heated Oxygen Sensor (HO2S) Inspection





HEATED OXYGEN SENSOR (HO2S) INSPECTION [MZI 3.7 V6]

HO2S Inspection

1. Warm up the engine to normal operating temperature.

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. On-Board Diagnostic Test






- VSS
- RPM
- O2S12, O2S22

- If not within the specification, replace the HO2S. Heated Oxygen Sensor (HO2S) Removal/Installation

HO2S Heater Inspection

1. Disconnect the negative battery cable. Removal and Replacement

2. Disconnect the HO2S connector.

3. Measure the resistance between HO2S terminals C and A.






- If it is not within the specification, replace the HO2S. Heated Oxygen Sensor (HO2S) Removal/Installation

HO2S heater resistance
- 2-50 ohms

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