Subaru 2009 IMPREZA, Service Manual

Page: 1615 / 3619

GD(H4DOTC)-27
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
5. DIAGNOSTIC METHOD
• Abnormality Judgement
Judge as NG when Low side or High side becomes NG.
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis :
Low: 3000 ms
High: 10000 ms
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cycles.
• Normality Judgement
Judge as OK and clear the NG when both Low side and High side become OK.
Judge as OK and clear the NG if the continuous time while the following conditions are established is more
than the predetermined time.
Time Needed for Diagnosis :
Low: Less than 1 second
High: Less than 1 second
Judgement Value
Malfunction Criteria Threshold Value
Low
Output voltage < 1.5 V
Engine speed
t
2500 rpm
Throttle opening angle
t
15 °
Intake manifold pressure
t
53.3 kPa (400 mmHg,
15.7 inHg)
High (1)
Output voltage
t
1.95 V
Engine speed 600 rpm — 900 rpm
Throttle opening angle < 4.1 °
Intake manifold pressure < 52.7 kPa (395 mmHg,
15.6 inHg)
High (2)
Output voltage
t
1.70 V
Engine speed 600 rpm — 900 rpm
Throttle opening angle < 4.1 °
Intake manifold pressure < 52.7 kPa (395 mmHg,
15.6 inHg)
Fuel system diagnosis Rich side malfunction
Judgement Value
Malfunction Criteria Threshold Value
Low
Output voltage
t
1.5 V
Engine speed
t
2500 rpm
Throttle opening angle
t
15 °
Intake manifold pressure
t
53.3 kPa (400 mmHg,
15.7 inHg)
High
Output voltage < 1.95 V
Engine speed 600 rpm — 900 rpm
Throttle opening angle < 4.1 °
Intake manifold pressure < 52.7 kPa (395 mmHg,
15.6 inHg)
Fuel system diagnosis Rich side normal