Subaru Legacy (2005 year). Manual - part 83

CO(H4SO 2.0)-7

COOLING

Radiator Fan System

2. Radiator Fan System

A: WIRING DIAGRAM

CO-02166

B135

F108

F16

B361

F17

F16

2 1

1
7

B360

1 2 3

4 5 6 7

8 9 10 11 12 13 14 15 16

F108

2 3

8

10

1
9

4

11 12 13 14 15 16

5 6 7

17 18

F27

13
14
15

16 17

27

24 25

26

20 21

22
23

29

30
31

28

8 9

10
11
12

1
2

5

3

4

7

6

19

18

B135

F36

F35

B143

5

6

7

2

1

3

4

29

10 11 12 13 14 15

25

24

16

30

9

8

17 18 19

20
28

21 22 23

32

31

26 27

33

34 35

F17

B361

1
7

2 3

4 5 6

8 9 10 11 12 13 14

F109

3 4

1 2

8 9 10 11

12 13 14 15 16 17 18 19 20 21 22 23 24

5

6 7

F27

1 2 3 4

5 6 7 8 9

10 11 12 13 14 15 16 17 18 19 20

1 2

3 4 5

6 7 8 9 10 11 12

3

1 2

7

4 5

6

16

7

1

2

3

4

5

21

22

E6

E5

C10

B7

C11

E3

1

2

20

23

E

E

M

2

1

M

F109

B360

10

1

SBF-6

MAIN SBF

No.3

No.22

No.26

B143

B:

F35

C:

F36

E:

1

2

B:

C:

E:

ECM

IGNITION
SWITCH

MAIN FUSE BOX (M/B)

MAIN
FAN
RELAY 1

MAIN
FAN
RELAY 2

SUB
FAN
RELAY

A/C RELAY HOLDER

THROUGH JOINT
CONNECTOR

THROUGH JOINT
CONNECTOR

MAIN FAN
MOTOR

SUB FAN
MOTOR

B134

5

6

7

8

2

1

9

4

3

10

24

22 23

25

11 12 13 14 15

26 27

28

16 17

18 19 20 21

33 34

29

32

30 31

A:

B134

A:

B:

*

*

1

*

2

*

2.5 L 

EC, EK, K4, EH, ER, 

MODEL: A31

EXCEPT FOR 2.5 L 

EC, EK, K4, EH, ER 

MODEL: A10

2.5 L 

EC, EK, K4, EH, ER, 

MODEL: B34

EXCEPT FOR 2.5 L 

EC, EK, K4, EH, ER 

MODEL: A9

B:

No.4

CO(H4SO 2.0)-8

COOLING

Radiator Fan System

B: INSPECTION

DETECTING CONDITION:
• Engine coolant temperature is more than 96

°C (205°F).

• Vehicle speed is below 19 km/h (12 MPH).
TROUBLE SYMPTOMS:
Radiator main and sub fan do not rotate under the above conditions.

Step

Check

Yes

No

1

CHECK OPERATION OF RADIATOR FAN.
1) Connect the test mode connector.
2) Turn the ignition switch to ON.
3) Perform the compulsory operation check for 
the radiator fan relay using Subaru Select 
Monitor.

NOTE:

• When performing the compulsory operation 
check for the radiator fan relay using Subaru 
Select Monitor, the radiator main fan and sub 
fan will repeat such a operation as low speed 
revolution 

→ high speed revolution → OFF in 

this order.
• Subaru Select Monitor
Refer to Compulsory Valve Operation Check 
Mode for more operation procedure. <Ref. to 
EN(H4SO 2.0)(diag)-39, Compulsory Valve 
Operation Check Mode.> or <Ref. to EN(H4SO 
2.5)(diag)-41, Compulsory Valve Operation 
Check Mode.>

Do the radiator main fan and 
sub fan rotate at low speed?

Go to step 2.

Go to step 3.

2

CHECK OPERATION OF RADIATOR FAN.
1) Connect the test mode connector.
2) Turn the ignition switch to ON.
3) Perform the compulsory operation check for 
the radiator fan relay using Subaru Select 
Monitor.

NOTE:

• When performing the compulsory operation 
check for the radiator fan relay using Subaru 
Select Monitor, the radiator main fan and sub 
fan will repeat such a operation as low speed 
revolution 

→ high speed revolution → OFF in 

this order.
• Subaru Select Monitor
Refer to Compulsory Valve Operation Check 
Mode for more operation procedure. <Ref. to 
EN(H4SO 2.0)(diag)-39, Compulsory Valve 
Operation Check Mode.> or <Ref. to EN(H4SO 
2.5)(diag)-41, Compulsory Valve Operation 
Check Mode.>

Do the radiator main fan and 
sub fan rotate at high speed?

Radiator fan sys-
tem is normal.

Go to step 27.

3

CHECK POWER SUPPLY TO SUB FAN RE-
LAY.
1) Turn the ignition switch to OFF.
2) Remove the sub fan relay from A/C relay 
holder.
3) Measure the voltage between sub fan relay 
terminal and chassis ground.

Connector & terminal

(F27) No. 20 (+) — Chassis ground (

−

):

Is the voltage more than 10 V? Go to step 4.

Go to step 5.

CO(H4SO 2.0)-9

COOLING

Radiator Fan System

4

CHECK POWER SUPPLY TO SUB FAN RE-
LAY.
1) Turn the ignition switch to ON.
2) Measure the voltage between sub fan relay 
terminal and chassis ground.

Connector & terminal

(F27) No. 23 (+) — Chassis ground (

−

):

Is the voltage more than 10 V? Go to step 7.

Go to step 6.

5

CHECK FUSE.
1) Turn the ignition switch to OFF.
2) Remove the fuse No. 3.
3) Check the condition of fuse.

Is the fuse blown out?

Replace the fuse.

Repair the power 
supply line.

6

CHECK FUSE.
1) Turn the ignition switch to OFF.
2) Remove the fuse No. 22.
3) Check the condition of fuse.

Is the fuse blown out?

Replace the fuse.

Repair the power 
supply line.

7

CHECK SUB FAN RELAY.
1) Turn the ignition switch to OFF.
2) Measure the resistance between sub fan 
relay terminals.

Terminal

No. 20 — No. 21:

Is the resistance more than 1 
M

Ω?

Go to step 8.

Replace the sub 
fan relay.

8

CHECK SUB FAN RELAY.
1) Connect the terminals No. 22 and No. 23 of 
sub fan relay to battery.
2) Measure the resistance between sub fan 
relay terminals.

Terminal

No. 20 — No. 21:

Is the resistance less than 1 
Ω?

Go to step 9.

Replace the sub 
fan relay.

9

CHECK HARNESS BETWEEN SUB FAN RE-
LAY TERMINAL AND SUB FAN MOTOR 
CONNECTOR.
1) Disconnect the connector from sub fan 
motor.
2) Measure the resistance of harness 
between sub fan relay terminal and sub fan 
motor connector.

Connector & terminal

(F16) No. 2 — (F27) No. 21:

Is the resistance less than 1 
Ω?

Go to step 10.

Repair the open 
circuit of harness 
between sub fan 
relay terminal and 
sub fan motor con-
nector.

10

CHECK HARNESS BETWEEN SUB FAN MO-
TOR CONNECTOR AND MAIN FAN RELAY 2 
CONNECTOR.
1) Remove the main fan relay 2 from A/C relay 
holder.
2) Measure the resistance of harness 
between sub fan motor connector and main fan 
relay 2 connector.

Connector & terminal

(F16) No. 1 — (F27) No. 5:

Is the resistance less than 1 
Ω?

Go to step 11.

Repair the open 
circuit of harness 
between sub fan 
motor connector 
and main fan relay 
2 connector.

11

CHECK POOR CONTACT.
Check the poor contact in sub fan motor con-
nector.

Is there poor contact in sub fan 
motor connector?

Repair the poor 
contact in sub fan 
motor connector.

Go to step 12.

12

CHECK SUB FAN MOTOR.
Connect the battery positive (+) terminal to 
terminal No. 2 of sub fan motor, and the 
ground (

−) terminal to terminal No. 1.

Does the sub fan rotate?

Go to step 13.

Replace the sub 
fan motor.

13

CHECK MAIN FAN RELAY 2.
Measure the resistance of main fan relay 2.

Terminal

No. 2 — No. 5:

Is the resistance less than 1 
Ω?

Go to step 14.

Replace the main 
fan relay 2.

Step

Check

Yes

No

CO(H4SO 2.0)-10

COOLING

Radiator Fan System

14

CHECK HARNESS BETWEEN MAIN FAN 
RELAY 2 TERMINAL AND MAIN FAN MO-
TOR CONNECTOR.
1) Disconnect the connector from main fan 
motor.
2) Measure the resistance of harness 
between main fan relay 2 terminal and main 
fan motor connector.

Connector & terminal

(F17) No. 2 — (F27) No. 2:

Is the resistance less than 1 
Ω?

Go to step 15.

Repair the open 
circuit of harness 
between main fan 
relay 2 terminal 
and main fan 
motor connector.

15

CHECK MAIN FAN MOTOR AND GROUND 
CIRCUIT.
Measure the resistance between main fan 
motor connector and chassis ground.

Connector & terminal

(F17) No. 1 — Chassis ground:

Is the resistance less than 5 
Ω?

Go to step 16.

Repair the open 
circuit of harness 
between main fan 
motor connector 
and chassis 
ground.

16

CHECK POOR CONTACT.
Check poor contact in main fan motor connec-
tor.

Is there poor contact in main 
fan motor connector?

Repair the poor 
contact in main fan 
motor connector.

Go to step 17.

17

CHECK MAIN FAN MOTOR.
Connect the battery positive (+) terminal to ter-
minal No. 2 of main fan motor, and the ground 
(

−) terminal to terminal No. 1.

Does the main fan rotate?

Go to step 18.

Replace the main 
fan motor.

18

CHECK HARNESS BETWEEN SUB FAN RE-
LAY AND ECM.
1) Disconnect the connector from ECM.
2) Measure the resistance between sub fan 
relay terminal and ECM connector.

Connector & terminal

2.5 L EC, EK, K4, EH, ER model

(B134) No. 31 — (F27) No. 22:

Except for 2.5 L EC, EK, K4, EH, ER model

(B134) No. 10 — (F27) No. 22:

Is the resistance less than 1 
Ω?

Go to step 19.

Repair the open 
circuit of harness 
between sub fan 
relay terminal and 
ECM.

19

CHECK POOR CONTACT.
Check poor contact in ECM connector.

Is there a poor contact in ECM 
connector?

Repair the poor 
contact in ECM 
connector.

Check the DTC. 
Repair the trouble 
cause. <Ref. to 
EN(H4SO 
2.0)(diag)-31, 
Read Diagnostic 
Trouble Code 
(DTC).> or <Ref. 
to EN(H4SO 
2.5)(diag)-32, 
Read Diagnostic 
Trouble Code 
(DTC).>

20

CHECK MAIN FAN RELAY 1.
1) Turn the ignition switch to OFF.
2) Remove the main fan relay 1 from main 
fuse box.
3) Measure the resistance of terminal in main 
fan relay 1 switch.

Is the resistance more than 1 
M

Ω?

Go to step 21.

Replace the main 
fan relay 1.

21

CHECK MAIN FAN RELAY 1.
1) Connect the battery to terminal of main fan 
relay 1 coil.
2) Measure the resistance between terminals 
of main fan relay 1 switch.

Is the resistance less than 1 
Ω?

Go to step 22.

Replace the main 
fan relay 1.

Step

Check

Yes

No