Subaru 2009 IMPREZA Service Manual page 1689

Diagnostic Trouble Code (DTC) Detecting Criteria
Combination valve one side closed pulse diagnosis
Perform close stuck diagnosis of the LH combination valve using delivery pipe pressure pulse when the RH
combination valve is closed.
Calculate the voltage pulse of the pump delivery pipe pressure when the RH combination valve is closed and
the LH combination valve is open. The calculation of delivery pipe pressure should be large when the LH
combination valve is open. Judge that the LH combination valve is close stuck if the calculation is small.
• 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
Pulse calculated value when the RH
combination valve is closed
Time Needed for Diagnosis: 4000 ms + 992 ms + 992 ms + 992 ms
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
Pulse calculated value when the RH
combination valve is closed
Time Needed for Diagnosis: 4000 ms + 992 ms + 992 ms + 992 ms
Perform close stuck diagnosis of the RH combination valve using delivery pipe pressure pulse when the LH
combination valve is closed.
Calculate the voltage pulse of the pump delivery pipe pressure when the LH combination valve is closed and
the RH combination valve is open. The calculation of delivery pipe pressure should be large when the RH
combination valve is open. Judge that the RH combination valve is close stuck if the calculation is small.
• 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
Pulse calculated value when the LH
combination valve is closed
Time Needed for Diagnosis: 4000 ms + 992 ms + 992 ms + 992 ms
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
Pulse calculated value when the LH
combination valve is closed
Time Needed for Diagnosis: 4000 ms + 992 ms + 992 ms + 992 ms
Threshold Value
< Value of Map 1 P2443
Threshold Value
Value of Map 1 P2443
Threshold Value
< Value of Map 2 P2441
Threshold Value
Value from Map 2 P2441
GD(H4DOTC)-101
GENERAL DESCRIPTION
DTC
DTC
DTC
DTC