Subaru Legacy (2005 year). Service manual — part 295

CO(H4DOTC)-11

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

(B135) No. 25 — (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 poor contact in ECM
connector?

Repair the poor
contact in ECM
connector.

Check the DTC.
Repair the trouble
cause. <Ref. to
EN(H4DOTC)(diag
)-29, Read Diag-
nostic 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 terminal of main fan relay 1
coil side terminal to battery.
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.

22

CHECK HARNESS BETWEEN MAIN FAN
RELAY 1 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 1 terminal and main
fan motor connector.

Connector & terminal

(F17) No. 2 — (F36) No. 6:

Is the resistance less than 1
Ω?

Go to step 23.

Repair the open
circuit of harness
between main fan
relay 1 terminal
and main fan
motor connector.

Step

Check

Yes

No

CO(H4DOTC)-12

COOLING

Radiator Fan System

23

CHECK HARNESS BETWEEN MAIN FAN
RELAY 1 AND ECM.
1) Disconnect the connector from ECM.
2) Measure the resistance between main fan
relay 1 terminal and ECM connector.

Connector & terminal

(B135) No. 24 — (B143) No. 7:

Is the resistance less than 1
Ω?

Go to step 24.

Repair the open
circuit of harness
between main fan
relay 1 terminal
and ECM.

24

CHECK HARNESS BETWEEN MAIN FAN
RELAY 2 AND ECM.
Measure the resistance between main fan
relay 2 terminal and ECM connector.

Connector & terminal

(B135) No. 24 — (F27) No. 3:

Is the resistance less than 1
Ω?

Go to step 25.

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

25

CHECK FUSE.
1) Turn the ignition switch to OFF.
2) Remove the fuse No. 2 and No. 26.
3) Check the condition of fuse.

Is the fuse blown out?

Replace the fuse.

Go to step 26.

26

CHECK POOR CONTACT.
Check poor contact in ECM connector.

Is there poor contact in ECM
connector?

Repair the poor
contact in ECM
connector.

Repair the power
supply circuit for
main fuse box.

27

CHECK OPERATION OF RADIATOR FAN.
Check if the sub fan rotates when both fans do
not rotate at high speed under the step 2.

Does the sub fan rotate?

Go to step 20.

Go to step 28.

28

CHECK GROUND CIRCUIT OF MAIN FAN
RELAY 2.
1) Remove the main fan relay 2 from A/C relay
holder.
2) Measure the resistance between main fan
relay 2 terminal and chassis ground.

Connector & terminal

(F27) No. 4 — Chassis ground:

Is the resistance less than 1
Ω?

Go to step 29.

Repair the open
circuit of harness
between main fan
relay 2 and chas-
sis ground.

29

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

Connector & terminal

(F27) No. 1 (+) — Chassis ground (

−

):

Is the voltage more than 10 V? Go to step 30.

Repair the power
supply line.

30

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

Terminals

(F27) No. 4 — (F27) No. 5:

Is the resistance more than 1
M

Ω?

Go to step 31.

Replace the main
fan relay 2.

31

CHECK MAIN FAN RELAY 2.
1) Connect the battery to terminals No. 1 and
No. 3 of main fan relay 2.
2) Measure the resistance of main fan relay 2.

Terminals

(F27) No. 4 — (F27) No. 5:

Is the resistance less than 1
Ω?

Go to step 23.

Replace the main
fan relay 2.

Step

Check

Yes

No

CO(H4DOTC)-13

COOLING

Engine Coolant

3. Engine Coolant

A: REPLACEMENT

1. DRAINING OF ENGINE COOLANT

1) Lift-up the vehicle.
2) Remove the under cover.
3) Remove the drain plug to drain engine coolant
into container.

NOTE:
Remove the coolant filler tank cap so that engine
coolant will drain faster.

4) Install the drain plug.

2. FILLING OF ENGINE COOLANT

1) Remove the collector cover.
2) Fill engine coolant into coolant filler tank up to
the filler neck position.

Coolant capacity (fill up to “FULL” level):

AT model (model with ATF warmer)

7.7

2(8.1 US qt, 7.1 Imp qt)

AT model (model without ATF warmer)

7.3

2(7.7 US qt, 6.4 Imp qt)

MT model

7.4

2(7.8 US qt, 6.5 Imp qt)

CAUTION:
Do not confuse the cap of coolant filler tank
with that of radiator.

NOTE:
• When pouring the engine coolant, the radiator
side cap must not be removed.
• The SUBARU Genuine Coolant containing anti-
freeze and anti-rust agents is especially made for
SUBARU engine, which has an aluminum crank-
case. Always use SUBARU Genuine Coolant,
since other coolant may cause corrosion.
3) Fill engine coolant into the reservoir tank up to
“FULL” level.
4) Close the coolant filler tank cap, start the engine
and race 5 to 6 times at less than 3,000 rpm, then
stop the engine. (Complete this operation within 40
seconds.)

5) Wait for one minute after the engine stops, open
the coolant filler tank cap. If the engine coolant lev-
el drops, add engine coolant to the filler neck posi-
tion of radiator.
6) Perform the procedures 4) and 5) again.
7) Attach the coolant filler tank cap and reservoir
tank cap properly.
8) Start the engine and operate the heater at max-
imum hot position and the blower speed setting to
“LO”.
9) Run the engine at 2,000 rpm or less until ratiator
fan starts and stops.

NOTE:
• Be careful with the engine coolant temperature
gauge to prevent overheating.
• If the radiator hose becomes harden by engine
coolant pressure at this time, air purge seems to be
mostly completed.
10) Stop the engine and wait until engine coolant
temperature lowers to 30

°C (86°F) or less.

11) Open the coolant filler tank cap. If the engine
coolant level drops, add engine coolant into the
coolant filler tank up to the filler neck position and
the reservoir tank to “FULL” level.
12) Attach the coolant filler tank cap and reservoir
tank cap properly.
13) Operate the heater at maximum hot position
and the blower speed setting to “LO” and start the
engine. Race at less than 3,000 rpm. If the flowing
sound is heard from heater core, repeat the proce-
dures from step 9).
14) Install the collector cover.

CO-00248

CO(H4DOTC)-14

COOLING

Engine Coolant

B: INSPECTION

1. RELATIONSHIP OF SUBARU COOLANT
CONCENTRATION AND FREEZING TEM-
PERTAURE

The concentration and safe operating temperature
of SUBARU coolant is shown in the diagram. Mea-
suring the temperature and specific gravity of the
coolant will provide this information.
[Example]
If the coolant temperature is 25

°C (77°F), its specif-

ic gravity is 1.054 and the concentration is 35%
(point A), the safe operating temperature is

−14°C

(7

°F) (point B), and the freezing temperature is −

20

°C (−4°F) (point C).

2. PROCEDURE TO ADJUST THE CON-
CENTRATION OF THE COOLANT

To adjust the concentration of coolant according to
temperature, find the proper fluid concentration in
the above diagram and replace the necessary
amount of coolant with an undiluted solution of
SUBARU genuine coolant (concentration 50%).
The amount of coolant that should be replaced can
be determined using the diagram.
[Example]
Assume that the coolant concentration must be in-
creased from 25% to 40%. Find point A, where the
25% line of coolant concentration intersects with
the 40% curve of the necessary coolant concentra-
tion, and read the scale on the vertical axis of the
graph at height A. The quantity of coolant to be
drained is 2.1

2(2.2 US qt, 1.8 Imp qt). Drain 2.1

2(2.2 US qt, 1.8 Imp qt) of coolant from the cooling
system and add 2.1

2(2.2 US qt, 1.8 Imp qt) of the

undiluted solution of SUBARU coolant.
If a coolant concentration of 50% is needed, drain
all the coolant and refill with the undiluted solution
only.

CO-02172

60%

(1.054)

1.000

1.010

1.020

1.030

1.040

1.050

1.060

1.070

1.080

1.090

1.100

Safe operating temperature

Freezing
temperature

Concentration
of coolant

Specific gravity

of coolant

Coolant temperature

B

A

C

-40

(-40) (-22) (-4) (14) (32) (50) (68) (86)

( F)

(104)

-30

-20 -10

0

10

20

30

40

(77 F)

50%

40%

30%

20%

25 C

10%

C

CO-00012

10

0

1

2

3

(1.1,
0.9)

(2.1,
1.8)

(3.2,
2.6)

10% 15%

25%

20%

30%

35%

40%

45%

A

20

30

40

50

Concentration of coolant in vehicie
and quantity to be drained

Quantity of coolant to be

drained (US qt, Imp qt)

Necessary Concentration
of coolant

Concentration of coolant in
the vehicie cooling system %