Subaru 2009 IMPREZA Service Manual page 343

Step
2 CHECK OPERATION OF RADIATOR FAN.
1) Connect the delivery (test) mode connector.
2) Turn the ignition switch to ON.
3) Using the Subaru Select Monitor, check the
forced operation of the radiator fan relay.
NOTE:
• When performing a forced operation radiator
fan relay check using the Subaru Select Moni-
tor, the radiator main fan and radiator sub fan
will repeat low speed revolution
revolution OFF in this order.
• Subaru Select Monitor
Refer to "Compulsory Valve Operation Check
Mode" for detailed procedures. <Ref. to
EN(H4SO)(diag)-56, Compulsory Valve Opera-
tion Check Mode.>
3 CHECK POWER SUPPLY TO SUB FAN RE-
LAY.
1) Turn the ignition switch to OFF.
2) Remove the sub fan relay from the relay
holder.
3) Measure the voltage between the sub fan
relay terminal and chassis ground.
Connector & terminal
(F27) No. 10 (+) — Chassis ground (–):
4 CHECK POWER SUPPLY TO SUB FAN RE-
LAY.
1) Turn the ignition switch to ON.
2) Measure the voltage between the sub fan
relay terminal and chassis ground.
Connector & terminal
(F27) No. 13 (+) — Chassis ground (–):
5 CHECK FUSE.
1) Turn the ignition switch to OFF.
2) Remove the fuse No. 3.
3) Check the condition of fuse.
6 CHECK FUSE.
1) Turn the ignition switch to OFF.
2) Remove the fuse No. 22.
3) Check the condition of fuse.
7 CHECK SUB FAN RELAY.
1) Turn the ignition switch to OFF.
2) Measure the resistance between sub fan
relay terminals.
Terminals
No. 10 — No. 11:
8 CHECK SUB FAN RELAY.
1) Connect the battery to terminals No. 13 and
No. 12 of the sub fan relay.
2) Measure the resistance between sub fan
relay terminals.
Terminals
No. 10 — No. 11:
Radiator Fan System
Check
Do the radiator main fans and
radiator sub fans rotate at high
speed?
high speed
Is the voltage 10 V or more?
Is the voltage 10 V or more?
Is the fuse blown out?
Is the fuse blown out?
Is the resistance 1 M or
more?
Is the resistance less than 1 ? Go to step 9.
CO(H4SO)-9
COOLING
Yes No
Radiator main fan Go to step 27.
system is normal.
Go to step 4. Go to step 5.
Go to step 7. Go to step 6.
Replace the fuse. Repair the power
supply line.
Replace the fuse. Repair the power
supply line.
Go to step 8. Replace the sub
fan relay. <Ref. to
AC-39, Relay and
Fuse.>
Replace the sub
fan relay. <Ref. to
AC-39, Relay and
Fuse.>