2004 SUBARU FORESTER ignition

CO(H4SO)-15
COOLING
Radiator Fan System
6 CHECK HARNESS OF FUSE TERMINAL
AND MAIN FAN RELAY TERMINAL.
1) Turn the ignition switch to OFF.
2) Measure the resistance between 20 A fuse
terminal and main fan relay terminal.
Te r m i n a l
No. 2 — No. 31:Is the resistance less than 1
Ω?Repair the power
supply line.Repair the open
harness.
7 CHECK FUSE.
1) Turn the ignition switch to OFF
2) Remove the fuse No. 18.
3) Check the condition of fuse.Is the fuse blown out? Replace the fuse. Repair the power
supply line.
8 CHECK MAIN FAN RELAY.
1) Turn the ignition switch to OFF.
2) Measure the resistance between main fan
relay terminals.
Te r m i n a l
No. 30 — No. 31:Is the resistance more than 1
MΩ?Go to step 9.Replace the main
fan relay.
9 CHECK MAIN FAN RELAY.
1) Connect the battery to main fan relay termi-
nals No. 32 and No. 34.
2) Measure the resistance between main fan
relay terminals.
Te r m i n a l
No. 30 — No. 31:Is the resistance less than 1
Ω?Go to step 10.Replace the main
fan relay.
10 CHECK HARNESS BETWEEN MAIN FAN
RELAY TERMINAL AND MAIN FAN MOTOR
CONNECTOR.
1) Disconnect the connector from main fan
motor.
2) Measure the resistance between main fan
relay terminal and main fan motor connector.
Connector & terminal
Turbo AT model
(F17) No. 1 — (F27) No. 30:
Except turbo AT model
(F17) No. 2 — (F27) No. 30:Is the resistance less than 1
Ω?Go to step 11.Repair the open
harness between
main fan relay ter-
minal and main fan
motor connector.
11 CHECK HARNESS BETWEEN MAIN FAN
MOTOR CONNECTOR AND FAN MODE RE-
LAY CONNECTOR.
1) Remove the fan mode relay from A/C relay
holder.
2) Measure the resistance between main fan
motor connector and fan mode relay connec-
tor.
Connector & terminal
Turbo AT model
(F17) No. 2 — (F27) No. 9:
Except turbo AT model
(F17) No. 1 — (F27) No. 9:Is the resistance less than 1
Ω?Go to step 12.Repair the open
harness between
main fan motor
connector and fan
mode relay con-
nector.
12 CHECK POOR CONTACT.
Check poor contact in main fan motor connec-
tor.Is there poor contact in main
fan motor connector?Repair poor con-
tact in main fan
motor connector.Go to step 13.
13 CHECK MAIN FAN MOTOR.
Connect the battery positive (+) terminal to ter-
minal No. 2 (except turbo AT model), No. 1
(turbo AT model), and ground (−) terminal to
terminal No. 1 (except turbo AT model), No. 2
(turbo AT model) of main fan motor.Does the main fan rotate? Go to step 14.Replace the main
fan motor with new
one. Step Check Yes No

CO(H4SO)-16
COOLING
Radiator Fan System
14 CHECK FAN MODE RELAY.
Measure the resistance of fan mode relay.
Te r m i n a l
No. 6 — No. 9:Is the resistance less than 1
Ω?Go to step 15.Replace the fan
mode relay.
15 CHECK RESISTANCE BETWEEN FAN
MODE RELAY TERMINAL AND SUB FAN
MOTOR CONNECTOR.
1) Disconnect the connector from sub fan
motor.
2) Measure the resistance between fan mode
relay terminal and sub fan motor connector.
Connector & terminal
Turbo AT model
(F16) No. 1 — (F27) No. 6:
Except turbo AT model
(F16) No. 2 — (F27) No. 6:Is the resistance less than 1
Ω?Go to step 16.Repair the open
harness between
fan mode relay ter-
minal and sub fan
motor connector.
16 CHECK SUB FAN MOTOR AND GROUND
CIRCUIT.
Measure the resistance between sub fan motor
connector and chassis ground.
Connector & terminal
Turbo AT model
(F16) No. 2 — Chassis ground:
Except turbo AT model
(F16) No. 1 — Chassis ground:Is the resistance less than 5
Ω?Go to step 17.Repair the open
harness between
sub fan motor con-
nector and chassis
ground.
17 CHECK POOR CONTACT.
Check poor contact in sub fan motor connec-
tor.Is there poor contact in sub fan
motor connector?Repair poor con-
tact in sub fan
motor connector.Go to step 18.
18 CHECK SUB FAN MOTOR.
Connect the battery positive (+) terminal to ter-
minal No. 2 (except turbo AT model), No. 1
(turbo AT model), and ground (−) terminal to
terminal No. 1 (except turbo AT model), No. 2
(turbo AT model) of sub fan motor.Does the sub fan rotate? Go to step 19.Replace the sub
fan motor with new
one.
19 CHECK HARNESS BETWEEN MAIN FAN
RELAY AND ECM.
1) Disconnect the connector from ECM.
2) Measure the resistance between fan relay 1
terminal and ECM connector.
Connector & terminal
Turbo model
(B135) No. 25 — (F27) No. 32:
Non-turbo model
(B134) No. 14 — (F27) No. 32:Is the resistance less than 1
Ω?Go to step 20.Repair the open
harness between
fan relay 1 terminal
and ECM.
20 CHECK POOR CONTACT.
Check poor contact in ECM connector.Is there poor contact in ECM
connector?Repair poor con-
tact in ECM con-
nector.Contact with SUB-
ARU dealers.
21 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. 28 (+) — Chassis ground (
−):Is the voltage more than 10 V? Go to step 22.Go to step 23. Step Check Yes No

CO(H4SO)-17
COOLING
Radiator Fan System
22 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. 25 (+) — Chassis ground (
−):Is the voltage more than 10 V? Go to step 26.Go to step 25.
23 CHECK FUSE.
1) Remove the fuse from A/C relay holder.
2) Check the condition of fuse.Is the fuse blown out? Replace the fuse. Go to step 24.
24 CHECK HARNESS BETWEEN FUSE TERMI-
NAL AND SUB FAN RELAY TERMINAL.
1) Turn the ignition switch to OFF.
2) Measure the resistance between fuse ter-
minal and sub fan relay terminal.
Te r m i n a l
No. 4 — No. 28:Is the resistance less than 1
Ω?Repair the power
supply line.Repair the open
harness.
25 CHECK FUSE.
1) Turn the ignition switch to OFF.
2) Remove the fuse No. 17.
3) Check the condition of fuse.Is the fuse blown out? Replace the fuse. Repair the power
supply line.
26 CHECK SUB FAN RELAY.
1) Turn the ignition switch to OFF.
2) Remove the sub fan relay from A/C relay
holder.
3) Measure the resistance of sub fan relay.
Te r m i n a l
No. 28 — No. 29:Is the resistance more than 1
MΩ?Go to step 27.Replace the sub
fan relay.
27 CHECK SUB FAN RELAY.
1) Connect the battery to terminals No. 25 and
No. 27 of sub fan relay.
2) Measure the resistance of sub fan relay.
Te r m i n a l
No. 28 — No. 29:Is the resistance less than 1
Ω?Go to step 28.Replace the sub
fan relay.
28 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 between sub fan
relay terminal and sub fan motor connector.
Connector & terminal
Turbo AT model
(F16) No. 1 — (F27) No. 29:
Except turbo AT model
(F16) No. 2 — (F27) No. 29:Is the resistance less than 1
Ω?Go to step 30.Repair the open
harness between
sub fan relay ter-
minal and sub fan
motor connector.
29 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
Non-turbo model: (B134) No. 13 — (F27)
No. 27:
Turbo model: (B135) No. 24 — (F27) No.
27:Is the resistance less than 1
Ω?Go to step 30.Repair the open
harness between
sub fan relay ter-
minal and ECM. Step Check Yes No

CO(H4SO)-18
COOLING
Radiator Fan System
30 CHECK HARNESS BETWEEN FAN MODE
RELAY AND ECM.
Measure the resistance between fan mode
relay terminal and ECM connector.
Connector & terminal
Non-turbo model
(B134) No. 13 — (F27) No. 7:
Turbo model
(B135) No. 24 — (F27) No. 7:Is the resistance less than 1
Ω?Go to step 31.Repair the open
harness between
fan mode relay ter-
minal and ECM.
31 CHECK POOR CONTACT.
Check poor contact in ECM connector.Is there poor contact in ECM
connector?Repair the poor
contact in ECM
connector.Contact with SUB-
ARU dealers.
N
OTE:
Probable cause is
deterioration of
multiple parts.
32 CHECK OPERATION OF RADIATOR FAN.Does the radiator main fan
rotate when the radiator main
and sub fan do not rotate at
high speed?Go to step 21.Go to step 33.
33 CHECK GROUND CIRCUIT OF FAN MODE
RELAY.
1) Remove the fan mode relay from A/C relay
holder.
2) Measure the resistance between fan mode
relay terminal and chassis ground.
Connector & terminal
(F27) No. 8 — Chassis ground:Is the resistance less than 1
Ω?Go to step 34.Repair the open
harness between
fan mode relay
and chassis
ground.
34 CHECK POWER SUPPLY TO FAN MODE
RELAY.
1) Turn the ignition switch to ON.
2) Measure the voltage between fan mode
relay terminal and chassis ground.
Connector & terminal
(F27) No. 5 (+) — Chassis ground (
−):Is the voltage more than 10 V? Go to step 35.Repair the power
supply line.
35 CHECK FAN MODE RELAY.
1) Turn the ignition switch to OFF.
2) Remove the fan mode relay.
3) Measure the resistance of fan mode relay.
Te r m i n a l
(F27) No. 8 — (F27) No. 9:Is the resistance more than 1
MΩ?Go to step 36.Replace the fan
mode relay.
36 CHECK FAN MODE RELAY.
1) Connect the battery to terminals No. 5 and
No. 7 of fan mode relay.
2) Measure the resistance of fan mode relay.
Te r m i n a l
(F27) No. 8 — (F27) No. 9:Is the resistance less than 1
Ω?Go to step 29.Replace the fan
mode relay. Step Check Yes No

CO(H4SO)-43
COOLING
Engine Cooling System Trouble in General
12.Engine Cooling System Trouble in General
A: INSPECTION
Trouble Possible cause Corrective action
Over-heatinga. Insufficient engine coolantReplenish the engine coolant, inspect for leakage, and
repair.
b. Loose timing belt Repair or replace the timing belt tensioner.
c. Oil on drive belt Replace.
d. Malfunction of thermostat Replace.
e. Malfunction of water pump Replace.
f. Clogged engine coolant passage Clean.
g. Improper ignition timingInspect and repair the ignition control system.

nostics Procedure.>
h. Clogged or leaking radiator Clean or repair, or replace.
i. Improper engine oil in engine coolant Replace the engine coolant.
j. Air/fuel mixture ratio too leanInspect and repair the fuel injection system.

nostics Procedure.>
k. Excessive back pressure in exhaust system Clean or replace.
l. Insufficient clearance between piston and cylinder Adjust or replace.
m. Slipping clutch Repair or replace.
n. Dragging brake Adjust.
o. Defective thermostat Replace.
p. Malfunction of radiator fanInspect the radiator fan relay, engine coolant tempera-
ture sensor or radiator motor and replace there.
Over-coolinga. Atmospheric temperature extremely low Partly cover the radiator front area.
b. Defective thermostat Replace.
Engine coolant
leaks.a. Loosened or damaged connecting units on hoses Repair or replace.
b. Leakage from water pump Replace.
c. Leakage from water pipe Repair or replace.
d. Leakage around cylinder head gasket Retighten the cylinder head bolts or replace gasket.
e. Damaged or cracked cylinder head and crankcase Repair or replace.
f. Damaged or cracked thermostat case Repair or replace.
g. Leakage from radiator Repair or replace.
Noisea. Defective drive belt Replace.
b. Defective radiator fan Replace.
c. Defective water pump bearing Replace the water pump.
d. Defective water pump mechanical seal Replace the water pump.

FUJI HEAVY INDUSTRIES LTD. G8080GE2
2004 FORESTER SERVICE MANUAL QUICK REFERENCE INDEX
ENGINE SECTION 1
This service manual has been prepared
to provide SUBARU service personnel
with the necessary information and data
for the correct maintenance and repair
of SUBARU vehicles.
This manual includes the procedures
for maintenance, disassembling, reas-
sembling, inspection and adjustment of
components and diagnostics for guid-
ance of experienced mechanics.
Please peruse and utilize this manual
fully to ensure complete repair work for
satisfying our customers by keeping
their vehicle in optimum condition.
When replacement of parts during
repair work is needed, be sure to use
SUBARU genuine parts.
All information, illustration and specifi-
cations contained in this manual are
based on the latest product information
available at the time of publication
approval.FUEL INJECTION (FUEL SYSTEM) FU(H4SO)
EMISSION CONTROL
(AUX. EMISSION CONTROL DEVICE)EC(H4SO)
INTAKE (INDUCTION) IN(H4SO)
MECHANICAL ME(H4SO)
EXHAUST EX(H4SO)
COOLING CO(H4SO)
LUBRICATION LU(H4SO)
SPEED CONTROL SYSTEM SP(H4SO)
IGNITION IG(H4SO)
STARTING/CHARGING SYSTEM SC(H4SO)
ENGINE (DIAGNOSTIC) EN(H4SO)

LU(H4SO)-8
LUBRICATION
Oil Pressure System
2. Oil Pressure System
A: WIRING DIAGRAM
LU-00102
E
i12
i10
i3
B38
B9
A3
B22
E3
14
E11
A:
B:
B:
i10
123456789101112131415161718192021222324252627282930219
32
1234 5610 11 12 13 14 15716
23 3019 20
22 26 27 28 29817
24 3118
25
i3B22
125678
131415169101112
34
17181920
**: 5
: 14
No.14SBF-4SBF-1
B72
14
B72i12
12345678910111213143412
TURBO MODEL NON-TURBO MODELBATTERY
IGNITION
SWITCH
COMBINATION
METER
OIL PRESSURE
WARNING LIGHT
OIL PRESSURE
SWITCH

LU(H4SO)-9
LUBRICATION
Oil Pressure System
B: INSPECTION
Step Check Yes No
1 CHECK COMBINATION METER.
1) Turn the ignition switch to ON. (engine
OFF)
2) Check other warning lights.Does the warning lights illumi-
nate?Go to step 2.Repair or replace
the combination
meter. 4, INSPECTION,
Combination
Meter System.>
2 CHECK HARNESS CONNECTOR BETWEEN
COMBINATION METER AND OIL PRES-
SURE SWITCH.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from oil pressure
switch.
3) Turn the ignition switch to ON.
4) Measure the voltage of harness between
the combination meter connector and chassis
ground.
Connector & terminal
(E11) No. 1 (+) — Chassis ground (
−):Is the voltage more than 10 V? Replace the oil
pressure switch.Go to step 3.
3 CHECK COMBINATION METER.
1) Turn the ignition switch to OFF.
2) Remove the combination meter.
3) Measure the resistance of combination
meter.
Te r m i n a l
No. B9 — No. A3:Is the resistance less than 10
Ω?Replace the har-
ness connector
between combina-
tion meter and oil
pressure switch.Repair or replace
the combination
meter and the oil
pressure switch
warning light bulb.