Subaru 2009 IMPREZA Service Manual page 777

Diagnostic Trouble Code (DTC) Detecting Criteria
5. DIAGNOSTIC METHOD
• Abnormality Judgement
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Judgement Value
Malfunction Criteria
Battery voltage
Time of heater control duty at 70 % or
more
Front oxygen (A/F) sensor impedance.
Time Needed for Diagnosis: 5000 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
• Normality Judgement
Judge as OK and clear the NG if the continuous time while the following conditions are established is more
than the predetermined time.
Judgement Value
Malfunction Criteria
Battery voltage
Front oxygen (A/F) sensor impedance.
Time Needed for Diagnosis: Less than 1 second
Threshold Value
10.9 V
36000 ms
> 500
Threshold Value
10.9 V
500
GD(H4SO)-53
GENERAL DESCRIPTION