Subaru 2009 IMPREZA Service Manual page 1563

Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
Step
1 CHECK OUTPUT SIGNAL OF ECM.
1) Turn the ignition switch to ON.
2) Measure the voltage between ECM and
chassis ground.
Connector & terminal
(B136) No. 7 (+) — Chassis ground (–):
2 CHECK HARNESS BETWEEN ECM AND
PURGE CONTROL SOLENOID VALVE 2
CONNECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connectors from ECM and
purge control solenoid valve 2.
3) Measure the resistance between the purge
control solenoid valve 2 connector and engine
ground.
Connector & terminal
(E52) No. 2 — Engine ground:
3 CHECK HARNESS BETWEEN ECM AND
PURGE CONTROL SOLENOID VALVE 2
CONNECTOR.
Measure the resistance of harness between
ECM and purge control solenoid valve 2.
Connector & terminal
(B136) No. 7 — (E52) No. 2:
4 CHECK PURGE CONTROL SOLENOID
VALVE 2.
1) Remove the purge control solenoid valve 2.
2) Measure the resistance between purge con-
trol solenoid valve 2 terminals.
Terminals
No. 1 — No. 2:
5 CHECK POWER SUPPLY TO PURGE CON-
TROL SOLENOID VALVE 2.
1) Turn the ignition switch to ON.
2) Measure the voltage between purge control
solenoid valve 2 and engine ground.
Connector & terminal
(E52) No. 1 (+) — Engine ground (–):
Check
Is the voltage 10 V or more?
Is the resistance 1 M or
more?
Is the resistance less than 1 ? Go to step 4.
Is the resistance 10 — 100 ? Go to step 5.
Is the voltage 10 V or more?
EN(H4DOTC)(diag)-342
Yes No
Repair the poor Go to step 2.
contact of ECM
connector.
Go to step 3. Repair the ground
short circuit of har-
ness between
ECM and purge
control solenoid
valve 2 connector.
Repair the harness
and connector.
NOTE:
In this case, repair
the following item:
• Open circuit of
harness between
ECM and purge
control
valve 2 connector
• Poor contact of
coupling connector
Replace the purge
control solenoid
valve 2. <Ref. to
EC(H4DOTC)-11,
Purge Control
Solenoid Valve.>
Repair the poor Repair the harness
contact of the and connector.
purge control sole-
NOTE:
noid valve 2 con-
In this case, repair
nector.
the following item:
• Open circuit of
harness between
the main relay and
purge control sole-
noid valve 2 con-
nector
• Poor contact of
coupling connector
• Poor contact of
main relay connec-
tor
solenoid