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Home >> Subaru >> 2007 >> Outback XT Limited, Standard >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Diagnostic Trouble Code (DTC) Detecting Criteria (H4DOTC) >> Diagnostic Trouble Code (DTC) Detecting Criteria >> DTC P1491 Positive Crankcase Ventilation (Blow-By) Function Problem >> Diagnostic Method
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Diagnostic Method

Judge as NG when the continuous time of meeting the malfunction criteria below becomes 2.5 seconds or more.

Judgment Value 

JUDGMENT VALUE

Malfunction Criteria Threshold Value
Battery voltage > 10.9 V
Engine speed ≥ 500 rpm
Positive crankcase ventilation diagnosis voltage High

Time Needed for Diagnosis:  2.5 seconds

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
Battery voltage > 10.9 V
Engine speed ≥ 500 rpm
Positive crankcase ventilation diagnosis voltage Low