Subaru 2009 IMPREZA Service Manual page 780

Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
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
High
Sensor output voltage
Low
Sensor output voltage
Time Needed for Diagnosis:
High: 2500 ms
Low (1): 20000 ms
Low (2): 40000 ms
Low (3): Value from Map
Map
Fuel Cut Time (second)
Time needed for diagnosis (second)
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
• 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
High
Sensor output voltage
Low
Sensor output voltage
Time Needed for Diagnosis
High: Less than 1 second
Low (1): Less than 1 second
Low (2): Less than 1 second
Low (3): Less than 1 second
AG:DTC P0138 O2 SENSOR CIRCUIT HIGH VOLTAGE (BANK 1 SENSOR 2)
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC P0137. <Ref. to GD(H4SO)-54, DTC P0137 O2 SENSOR CIRCUIT
LOW VOLTAGE (BANK 1 SENSOR 2), Diagnostic Trouble Code (DTC) Detecting Criteria.>
Threshold Value
P0138
> 1.2 V
P0137
< 0.03 V
0
40000
Threshold Value
P0138
1.2 V
P0137
0.03 V
GD(H4SO)-56
DTC
2000 10000
40000 60000
DTC