Subaru Legacy IV (2008 year). Service manual — part 80

CO(H4SO)-6

General Description

COOLING

D: PREPARATION TOOL

1. SPECIAL TOOL

2. GENERAL TOOL

ILLUSTRATION

TOOL NUMBER

DESCRIPTION

REMARKS

499977100

CRANK PULLEY
WRENCH

Used to stop rotation of the crank pulley
when loosening or tightening crank pulley
bolts. (MT model)

499977400

CRANK PULLEY
WRENCH

Used to stop rotation of the crank pulley
when loosening or tightening crank pulley
bolts. (AT model)

18231AA010

CAM SPROCKET
WRENCH

• Used for removing and installing cam
sprocket.
• CAM SPROCKET WRENCH (499207100)
can also be used.

1B022XU0

SUBARU SELECT
MONITOR III KIT

Used for troubleshooting the electrical sys-
tem.

TOOL NAME

REMARKS

Radiator cap tester

Used for checking radiator and radiator cap.

ST-499977100

ST-499977400

ST18231AA010

ST1B022XU0

CO(H4SO)-7

Radiator Fan System

COOLING

2. Radiator Fan System

A: WIRING DIAGRAM

B136

F108

F16

B361

F17

F16

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

B136

F36

F35

B143

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

22

19

18

11

12

20

21

10

13

E

E

M

2

1

M

2

F109

B360

10

1

SBF-6

MAIN SBF

No.3

No.22

No.26

18

29

B:

C:

E:

ECM

No.4

BATTERY

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

35

20 21 22

19

18

3 4 5

7

6

10 11

12
13

15

16
17

14

2

1

9

8

E6

E5

C10

B7

MAIN FAN
RELAY 1

MAIN
FUSE BOX

(M/B)

B143

B:

F35

C:

F36

E:

2 1

CO-02319

MAIN FAN
MOTOR

SUB FAN MOTOR

SUB
FAN
RELAY

MAIN
FAN
RELAY

THROUGH JOINT CONNECTOR

RELAY
HOLDER

IGNITION SWITCH

THROUGH JOINT
CONNECTOR

CO(H4SO)-8

Radiator Fan System

COOLING

B: INSPECTION

DETECTING CONDITION:

TROUBLE SYMPTOMS:
Radiator main fan and radiator sub fans do not rotate under the above operating conditions.

Vehicle speed

A/C compressor

load

Engine coolant temperature

Increase: 94°C (201°F)

or less

Decrease: 92°C

(198°F) or less

Increase: 95 — 99°C

(203 — 210°F)

Decrease: 93 — 94°C

(199 — 201°F)

Increase: 100°C

(212°F) or more
Decrease: 95°C
(203°F) or more

Radiator fan operation

Radiator fan operation

Radiator fan operation

During acceleration:

19 km/h (12 MPH) or less

During deceleration:

10 km/h (6 MPH) or less

OFF

OFF

Low-Speed

High-Speed

Low

Low-Speed

Low-Speed

High-Speed

High

High-Speed

High-Speed

High-Speed

During acceleration:

20 — 69 km/h (12 — 43 MPH)

During deceleration:

11 — 64 km/h (7 — 40 MPH)

OFF

OFF

Low-Speed

High-Speed

Low

High-Speed

High-Speed

High-Speed

High

High-Speed

High-Speed

High-Speed

During acceleration:

70 — 134 km/h (43 — 83 MPH)

During deceleration:

65 — 129 km/h (40 — 80 MPH)

OFF

OFF

Low-Speed

High-Speed

Low

OFF

Low-Speed

High-Speed

High

Low-Speed

High-Speed

High-Speed

During acceleration:

135 km/h (84 MPH) or more

During deceleration:

130 km/h (81 MPH) or more

OFF

OFF

OFF

High-Speed

Low

OFF

Low-Speed

High-Speed

High

OFF

Low-Speed

High-Speed

Step

Check

Yes

No

1

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

o high speed

revolution

o OFF in this order.

• Subaru Select Monitor
Refer to “Compulsory Valve Operation Check
Mode” for detailed procedures. <Ref. to
EN(H4SO)(diag)-51, Compulsory Valve Opera-
tion Check Mode.>

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

Go to step 2.

Go to step 3.

CO(H4SO)-9

Radiator Fan System

COOLING

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

o high speed

revolution

o OFF in this order.

• Subaru Select Monitor
Refer to “Compulsory Valve Operation Check
Mode” for detailed procedures. <Ref. to
EN(H4SO)(diag)-51, Compulsory Valve Opera-
tion Check Mode.>

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

Radiator main fan
system 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 the relay
holder.
3) Measure the voltage between the sub fan
relay terminal and chassis ground.

Connector & terminal

(F27) No. 10 (+) — Chassis ground (–):

Is the voltage 10 V or more?

Go to step 4.

Go to step 5.

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 (–):

Is the voltage 10 V or more?

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.

Terminals

No. 10 — No. 11:

Is the resistance 1 M

: or

more?

Go to step 8.

Replace the sub
fan relay. <Ref. to
AC-41, Relay and
Fuse.>

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:

Is the resistance less than 1

:? Go to step 9.

Replace the sub
fan relay. <Ref. to
AC-41, Relay and
Fuse.>

Step

Check

Yes

No