Subaru 2009 IMPREZA, Service Manual

Page: 1629 / 3619

GD(H4DOTC)-41
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
5. DIAGNOSTIC METHOD
• Abnormality Judgement
Judge as NG if the criteria below are met.
Timer for diagnosis after engine start
a. Timer stop at fuel cut
b. During the driving conditions except a) above, timer counts up as follows.
64 millis TWCNT milliseconds (the time of at 64 milliseconds)
TWCNT is defined as follows,
TWCNT = 0 at idle switch ON,
TWCNT show on the following table at idle switch OFF.
Judgement value of timer after engine starting
t = 451056 ms – 25870 ms × Ti
Ti : The lowest coolant temperature after engine start
Time Needed for Diagnosis: Less than 1 second
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
• Normality Judgement
Judge as OK and clear the NG when the malfunction criteria below are met.
Time Needed for Diagnosis: Less than 1 second
Judgement Value
Malfunction Criteria Threshold Value
Engine coolant temperature < 20 °C (68 °F)
Timer for diagnosis after engine start
t
Judgement value of
timer after engine start
Vehicle speed km/h (MPH)
0 (0) 8 (5) 16 (9.9) 24 (14.9) 32 (19.9) 40 (24.9) 48 (29.8) 56 (34.8)
Temperature
°C (°F)
–20 (–4) 0 ms 37.136 ms 74.272 ms 111.41 ms 126.66 ms 141.91 ms 163.59 ms 185.26 ms
–10 (14) 0 ms 27.391 ms 54.782 ms 82.173 ms 99.65 ms 117.13 ms 135.96 ms 154.8 ms
0 (32) 0 ms 17.646 ms 35.292 ms 52.938 ms 72.64 ms 92.341 ms 108.34 ms 124.33 ms
10 (50) 0 ms 7.9012 ms 15.802 ms 23.704 ms 45.63 ms 67.556 ms 80.711 ms 93.867 ms
20 (68) 0 ms 7.9012 ms 15.802 ms 23.704 ms 45.63 ms 67.556 ms 80.711 ms 93.867 ms
Judgement Value
Malfunction Criteria Threshold Value
Engine coolant temperature
t
20 °C (68 °F)