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Home >> Mazda >> 2010 >> 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]

Sensor Output Value Inspection (HO2S)

1. Perform the inspection according to the following procedure using the PID/DATA monitor function. Diagnostic Monitoring Test Results

- Start the engine and warm it up.
- Drive the vehicle.
- 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





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

Resistance Inspection (HO2S heater)

1. Disconnect the HO2S connector.

2. 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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