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Home >> Subaru >> 2007 >> Outback XT Limited, Standard >> Repair and Diagnosis (Single Page) >> Engine Performance >> Testing & Diagnosis >> Diagnostic Trouble Code (DTC) Detecting Criteria (H4DOTC) >> Diagnostic Trouble Code (DTC) Detecting Criteria >> DTC P0031 Ho2S Heater Control Circuit Low (Bank 1 Sensor 1) >> Diagnostic Method
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Diagnostic Method

Judge as NG when the continuous time of meeting the malfunction criteria below becomes 1 second (8 cycles) or more.

Judgment Value 

JUDGMENT VALUE

Malfunction Criteria Threshold Value
Output voltage level Low
Front oxygen (A/F) sensor heater control duty < 87.5%

Time Needed for Diagnosis:  1 second

Malfunction Indicator Light Illumination:  Illuminates as soon as a malfunction occurs.

Judge as OK and clear the NG when the malfunction criteria below are met.

Judgment Value 

JUDGMENT VALUE

Malfunction Criteria Threshold Value
Output voltage level High