Subaru IMPREZA 2004 Service Manual page 121

Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
Step
1 CHECK HARNESS BETWEEN GENERATOR
AND ECM CONNECTOR.
1)Turn the ignition switch to OFF.
2)Disconnect the connectors from generator
and ECM.
3)Measure the resistance of harness between
generator connector and engine ground.
Connector & terminal
(F26) No. 3 — Engine ground:
2 CHECK HARNESS BETWEEN GENERATOR
AND ECM CONNECTOR.
Measure the resistance of harness between
ECM and generator of harness connector.
Connector & terminal
(B136) No. 25 — (F26) No. 3:
Check
Is the resistance more than 1
MΩ?
Is the resistance less than 1
Ω?
EN(H4SO)(diag)-198
Yes
Go to step 2. Repair the ground
short circuit in har-
ness between
ECM and purge
control solenoid
valve connector.
Repair poor con- Repair the open
tact in connector. circuit in harness
between ECM and
generator connec-
tor.
NOTE:
In this case, repair
the following:
• Open circuit in
harness between
ECM and genera-
tor connector
• Poor contact in
coupling connector
No