Subaru 2002 IMPREZA Service Manual page 689

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Step
1 CHECK POWER SUPPLY TO IDLE AIR CON-
TROL SOLENOID VALVE.
1)Turn the ignition switch to OFF.
2)Disconnect the connector from idle air con-
trol solenoid valve.
3)Turn the ignition switch to ON.
4)Measure the voltage between idle air control
solenoid valve connector and engine ground.
Connector & terminal
(E7) No. 2 (+) — Engine ground ( − − − − ):
2 CHECK POWER SUPPLY TO IDLE AIR CON-
TROL SOLENOID VALVE.
Measure the voltage between idle air control
solenoid valve connector and engine ground.
Connector & terminal
(E7) No. 5 (+) — Engine ground ( − − − − ):
3 CHECK HARNESS BETWEEN ECM AND
IDLE AIR CONTROL SOLENOID VALVE
CONNECTOR.
1)Turn the ignition switch to OFF.
2)Measure the resistance between ECM and
idle air control solenoid valve connector.
Connector & terminal
DTC P1510; (B134) No. 5 — (E7) No. 4:
DTC P1512; (B134) No. 6 — (E7) No. 1:
DTC P1514; (B134) No. 19 — (E7) No. 6:
DTC P1516; (B134) No. 20 — (E7) No. 3:
4 CHECK HARNESS BETWEEN ECM AND
IDLE AIR CONTROL SOLENOID VALVE
CONNECTOR.
1)Disconnect the connector from ECM.
2)Measure the resistance between ECM con-
nector and chassis ground.
Connector & terminal
DTC P1510; (B134) No. 5 — Chassis
ground:
DTC P1512; (B134) No. 6 — Chassis
ground:
DTC P1514; (B134) No. 19 — Chassis
ground:
DTC P1516; (B134) No. 20 — Chassis
ground:
Check
Is the voltage more than 10 V? Go to step 2.
Is the voltage more than 10 V? Go to step 3.
Is the resistance less than 1
Ω?
Is the resistance less than 10
Ω?
EN-257
ENGINE (DIAGNOSTICS)
Yes
Repair the har-
ness and connec-
tor.
NOTE:
In this case, repair
the following:
• Open circuit in
harness between
idle air control
solenoid valve and
main relay con-
nector
• Poor contact in
coupling connector
(B22)
Repair the har-
ness and connec-
tor.
NOTE:
In this case, repair
the following:
• Open circuit in
harness between
idle air control
solenoid valve and
main relay con-
nector
• Poor contact in
coupling connector
(B22)
Go to step 4. Repair the har-
ness and connec-
tor.
NOTE:
In this case, repair
the following:
• Open circuit in
harness between
ECM and idle air
control solenoid
valve connector
• Poor contact in
coupling connector
(B21)
Repair the ground Go to step 5.
short circuit in har-
ness between
ECM and idle air
control solenoid
valve connector.
No