Subaru 2001 IMPREZA User manual

FUJI HEAVY INDUSTRIES LTD. G1830GE2
2001 IMPREZA SERVICE MANUAL QUICK REFERENCE INDEX
ENGINE 1 SECTION
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 SYSTEMS) FU(SOHC)
EMISSION CONTROL
(AUX. EMISSION CONTROL DEVICES) EC(SOHC)
INTAKE (INDUCTION) IN(SOHC)
MECHANICAL ME(SOHC)
EXHAUST EX(SOHC)
COOLING CO
LUBRICATION LU
SPEED CONTROL SYSTEMS SP
IGNITION IG(SOHC)
STARTING/CHARGING SYSTEMS SC
ENGINE (DIAGNOSTICS) EN(SOHC)

COOLING CO
Page
1. General Description ....................................................................................2
2. Radiator Main Fan System..........................................................................9
3. Radiator Sub Fan System.........................................................................17
4. Engine Coolant..........................................................................................25
5. Water Pump..............................................................................................27
6. Thermostat................................................................................................35
7. Radiator.....................................................................................................37
8. Radiator Cap.............................................................................................45
9. Radiator Main Fan and Fan Motor ............................................................46
10. Radiator Sub Fan and Fan Motor..............................................................48
11. Reservoir Tank..........................................................................................50
12. Coolant Filler Tank....................................................................................51
13. Engine Cooling System Trouble in General..............................................52

CO-2
COOLING GENERAL DESCRIPTION
1. General Description
A: SPECIFICATIONS
Model Non-turbo Turbo
Cooling system Electric fan + Forced engine coolant circulation sys-
tem
Total engine coolant capacity 2(US qt, Imp qt)
1.6AT: Approx. 7.3
(7.71, 6.42)
1.6MT: Approx. 7.4
(7.82, 6.51)
2.0AT: Approx. 6.9
(7.29, 6.07)
2.0MT: Approx. 7
(7.4, 6.2)
Approx. 7.7
(8.14, 6.78)
Water pump
Type Centrifugal impeller type
Discharge performance I
Discharge 20 2(5.3 US gal, 4.4 Imp gal)/min.
Pump speed—total engine
coolant head 700 rpm —0.3 mAq (1.0 ftAq)
Engine coolant temperature 85°C (185°F)
Discharge performance II
Discharge 100 2(26.4 US gal, 22.0 Imp gal)/min.
Pump speed—total engine
coolant head 3,000 rpm —5.0 mAq (16.4 ftAq)
Engine coolant temperature 85°C (185°F)
Discharge performance III
Discharge 200 2(52.8 US gal, 44.0 Imp gal)/min.
Pump speed—total engine
coolant head 6,000 rpm —23.0 mAq (75.5 ftAq)
Engine coolant temperature 85°C (185°F)
Impeller diameter 76 mm (2.99 in)
Number of impeller vanes 8
Pump pulley diameter 60 mm (2.36 in)
Clearancebetweenimpeller
and case Standard 0.5 —0.7 mm (0.020 —0.028 in)
Limit 1.0 mm (0.039 in)
“Thrust”runout of impeller end 0.5 mm (0.020 in)
Thermostat
Type Wax pellet type
Starts to open 76 —80°C (169 —176°F)
Fully opened 91°C (196°F)
Valve lift 9.0 mm (0.354 in) or more
Valve bore 35 mm (1.38 in)
Radiator fan Motor Main fan 70 W 120 W
Sub fan 70 W 120 W
Fan diameter ×Blade 320 mm (11.81 in) ×5 (main fan)
320 mm (11.81 in) ×7 (sub fan)
Radiator
Type Down flow, pressure type
Core dimensions 691.5 ×340 ×16 mm
(27.22 ×13.39 ×0.63 in) 691.5 ×340 ×27 mm (27.22 ×13.39 ×1.06 in)
Pressure range in which cap valve is open
Above: 108±15 kPa
(1.1±0.15 kg/cm2, 16±2 psi)
Below: −1.0 to −4.9 kPa
(−0.01 to −0.05 kg/cm2, −0.1 to −0.7 psi)
Fins Corrugated fin type
Reservoir
tank Capacity 0.5 2(0.5 US qt, 0.4 Imp qt)

CO-3
COOLING
GENERAL DESCRIPTION
B: COMPONENT
1. WATER PUMP
•NON-TURBO MODEL
H2M2354A
(1) Water pump ASSY (5) Gasket Tightening torque: N·m (kgf-m, ft-lb)
(2) Gasket (6) Thermostat cover T1: First 12 (1.2, 8.7)
Second 12 (1.2, 8.7)
(3) Heater by-pass hose
(4) Thermostat T2: 6.4 (0.65, 4.7)

CO-4
COOLING GENERAL DESCRIPTION
•TURBO MODEL
H2M1785B
(1) Thermostat case (6) Header by-pass hose Tightening torque: N·m (kgf-m, ft-lb)
(2) Gasket (7) Coolant filler tank by-pass hose T1: First 12 (1.2, 8.7)
Second 12 (1.2, 8.7)
(3) Thermostat (8) Water by-pass pipe
(4) Water pump ASSY T2: 6.4 (0.65, 4.7)
(5) Gasket

CO-5
COOLING
GENERAL DESCRIPTION
2. RADIATOR AND RADIATOR FAN
•NON-TURBO MODEL
EN0068
T3 T5 T5
T2
T2
T4
T4
T1
T1
(10)
(13)
(15)
(8)
(7)
(9)
(16)
(16)
(16)
(16)
(16)
(16)
(5)
(5)
(5)
(6)
(22)
(1)
(2)
(23)
(24)
(3)
(4)
(21)
(20) (19)
(17)
(18)
(12)
(11)
(14)
T5
(1) Radiator lower cushion (13) Main fan shroud (23) Radiator lower bracket
(2) Radiator (14) Radiator main fan (24) Radiator drain plug
(3) Radiator upper cushion (15) Main fan motor
(4) Radiator upper bracket (16) ATF hose clamp (AT vehicles only) Tightening torque: N·m (kgf-m, ft-lb)
(5) Clamp (17) ATF inlet hose A (AT vehicles only) T1: 4.4 (0.45, 3.3)
(6) Radiator inlet hose (18) ATF outlet hose A (AT vehicles
only) T2: 12 (1.2, 8.7)
(7) Engine coolant reservoir tank cap T3: 18 (1.8, 13.0)
(8) Over flow hose (19) ATF pipe (AT vehicles only) T4: 3.4 (0.35, 2.5)
(9) Engine coolant reservoir tank (20) ATF inlet hose B (AT vehicles only) T5: 4.9 (0.50, 3.6)
(10) Sub fan shroud (21) ATF outlet hose B (AT vehicles
only)
(11) Radiator sub fan
(12) Sub fan motor (22) Radiator outlet hose

CO-6
COOLING GENERAL DESCRIPTION
•TURBO MODEL
EN0069
T5
(13) (16)
(7)
(20)
(19)
(5)
(5)
(21)
(9)
T5
T4
T4
T4
T1
T1
(12)
(15)
(11)
(14)
T3
(5)
(5)
(5)
(5)
(6)
(17)
(1)
(23)
(18)
(3)
(4)
(8)
(2)
(10)
(1) Radiator lower cushion (10) Over flow pipe (19) Engine coolant filler tank
(2) Radiator (11) Sub fan shroud (20) Engine coolant filler tank cap
(3) Radiator upper cushion (12) Radiator sub fan (21) Engine coolant hose
(4) Radiator upper bracket (13) Radiator sub fan motor
(5) Clamp (14) Main fan shroud Tightening torque: N·m (kgf-m, ft-lb)
(6) Radiator inlet hose (15) Radiator main fan T1: 4.4 (0.45, 3.3)
(7) Engine coolant reservoir tank cap (16) Radiator main fan motor T2: 18 (1.8, 13.0)
(8) Over flow hose (17) Radiator outlet hose T3: 3.4 (0.35, 2.5)
(9) Engine coolant reservoir tank (18) Radiator drain plug T4: 4.9 (0.50, 3.6)

CO-7
COOLING
GENERAL DESCRIPTION
C: CAUTION
•Wear working clothing, including a cap, protec-
tive goggles, and protective shoes during opera-
tion.
•Remove contamination including dirt and corro-
sion before removal, installation or disassembly.
•Keep the disassembled parts in order and pro-
tect them from dust or dirt.
•Before removal, installation or disassembly, be
sure to clarify the failure. Avoid unnecessary re-
moval, installation, disassembly, and replacement.
•Be careful not to burn your hands, because each
part in the vehicle is hot after running.
•Be sure to tighten fasteners including bolts and
nuts to the specified torque.
•Place shop jacks or safety stands at the specified
points.
•Before disconnecting electrical connectors of
sensors or units, be sure to disconnect negative
terminal from battery.

CO-8
COOLING GENERAL DESCRIPTION
D: PREPARATION TOOL
ILLUSTRATION TOOL NUMBER DESCRIPTION REMARKS
499977300 CRANK PULLEY
WRENCH Used for stopping crankshaft pulley when loosening and tightening crankshaft pulley
bolts.
499207100 CAMSHAFT
SPROCKET
WRENCH
Used for removing and installing camshaft
sprocket. (Non-turbo LH side only)
499207400 CAMSHAFT
SPROCKET
WRENCH
Used for removing and installing camshaft
sprocket.
B2M4157
B2M3859
B2M4158

CO-9
COOLING
RADIATOR MAIN FAN SYSTEM
2. Radiator Main Fan System
A: SCHEMATIC
1. NON-TURBO MODEL
BATTERY SBF-1 No.3
No.17
No.18
SBF-4
B72 IGNITION
SWITCH
F27 20A
AIR CONDITIONING
RELAY HOLDER
F29 SUB
FAN
RELAY
SUB FAN
MOTOR
3
4
18
20
19
17
F16
2
1
F27 20A
AIR CONDITIONING
RELAY HOLDER
F66 MAIN
FAN
RELAY
MAIN FAN
MOTOR
1
2
26
28
27
25
F17
2
1
2 1
B134 ECM
F45
B62
12
3
LHD :2
RHD :7
LHD :12
RHD :17
1
2
F17
2 1
F16
F67
F27 F28
1 2
3 4
5 6
7
8
9
10
11 12
13 14
15
16
17
18
19 20
21 22
23
24
25
26
27 28
29
30
F31
F29 F66
F30
B134
1 2 3 4 5 6 7 8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
24 25 26 27 28 29 30 31 32 33 34 35
F45
3412 89
10 11
12 13 14 15 16 17 18 19 20 21 22 23 24
567
F45
1234 56789
10 11 12 13 14 15 16 17 18 19 20
LHD: RHD:
EN0880

CO-10
COOLING RADIATOR MAIN FAN SYSTEM
2. TURBO MODEL
EN0260
No.18
No.17
E E
IGNITION
SWITCH
SBF-4
SBF-1
B62
B72
F45
SUB FAN
RELAY2
30A
F16
B137 ECM 17
28
BATTERY
F17
F29
F29
B72 (BLUE)
(LHD)
(RHD)
F27
F27 F45 F16
F17
SUB FAN
RELAY1
F28
F28
MAIN FAN
RELAY2
AIR CONDITIONING RELAY HOLDER
F30
F30 F66 B137
MAIN FAN
RELAY1
F66
30A
34
12 1 2
3 4
5 6
7
8
9
10
11 12
13 14
15
16
17
18
19 20
21 22
23
24
25
26
27 28
29
30
12 78956 34
10 11 12 19 20 21
29 30 31
13 14 15 16 17
27 28 18 22 23 24 25 26
3412 89 10 11
12 13 14 15 16 17 18 19 20 21 22 23 24
567
1 3 2
SUB FAN
MOTOR
M
1 3 2
MAIN FAN
MOTOR
M
17 19 20 18 24 22 21 23 25 27 28 26
6 5 7 2 1 4 3 8
2
1
*
*
1
23
1234 56
9
10 11 12 13 14
7
15 18
8
16 17
LHD : 2
RHD : 7
LHD : 12
RHD : 17
*1
*2

CO-11
COOLING
RADIATOR MAIN FAN SYSTEM
B: INSPECTION
1. NON-TURBO MODEL
DETECTING CONDITION:
Condition:
•Engine coolant temperature is above 95°C
(203°F).
•Vehicle speed is below 19 km/h (12 MPH).
TROUBLE SYMPTOM:
•Radiator main fan does not rotate under the
above conditions.
Step Check Yes No
1 CHECK POWER SUPPLY TO MAIN FAN MO-
TOR.
CAUTION:
Be careful not to overheat engine during re-
pair.
1)Turn ignition switch to OFF.
2)Disconnect connector from main fan motor.
3)Start the engine, and warm it up until engine
coolant temperature increases over 95°C
(203°F).
4)Stop the engine and turn ignition switch to
ON.
5)Measure voltage between main fan motor
connector and chassis ground.
Connector & terminal
(F17) No. 2 (+) —Chassis ground (
−
−−
−
):
Is the voltage more than 10 V? Go to step 2. Go to step 5.
2 CHECK GROUND CIRCUIT OF MAIN FAN
MOTOR.
1)Turn ignition switch to OFF.
2)Measure 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 3. Repairopencircuit
in harness
between main fan
motor connector
and chassis
ground.
3 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 4.
4 CHECK MAIN FAN MOTOR.
Connect battery positive (+) terminal to termi-
nal No. 2, and negative (−) terminal to terminal
No. 1 of main fan motor connector.
Does the main fan rotate? Repair poor con-
tact in main fan
motor connector.
Replace main fan
motor with a new
one.
5 CHECK POWER SUPPLY TO MAIN FAN RE-
LAY.
1)Turn ignition switch to OFF.
2)Remove main fan relay from A/C relay
holder.
3)Measure voltage between main fan relay ter-
minal and chassis ground.
Connector & terminal
(F66) No. 26 (+) —Chassis ground (
−
−−
−
):
Is the voltage more than 10 V? Go to step 6. Go to step 7.
6 CHECK POWER SUPPLY TO MAIN FAN RE-
LAY.
1)Turn ignition switch to ON.
2)Measure voltage between main fan relay ter-
minal and chassis ground.
Connector & terminal
(F66) No. 28 (+) —Chassis ground (
−
−−
−
):
Is the voltage more than 10 V? Go to step 10. Go to step 9.
7 CHECK 20 A FUSE.
1)Remove 20 A fuse from A/C relay holder.
2)Check condition of fuse.
Is the fuse blown-out? Replace fuse. Go to step 8.

CO-12
COOLING RADIATOR MAIN FAN SYSTEM
NOTE:
Inspection by your Subaru distributor is required,
because probable cause is deterioration of multiple
parts.
8 CHECK POWER SUPPLY TO A/C RELAY
HOLDER 20 A FUSE TERMINAL.
Measure voltage of harness between A/C relay
holder 20 A fuse terminal and chassis ground.
Connector & terminal
(F27) No. 1 (+) —Chassis ground (
−
−−
− ):
Is the voltage more than 10 V? Repairopencircuit
in harness
between 20 A fuse
and main fan relay
terminal.
Repairopencircuit
in harness
betweenmainfuse
box connector and
20 A fuse terminal.
9 CHECK FUSE.
1)Turn ignition switch to OFF.
2)Remove fuse No. 18 from joint box.
3)Check condition of fuse.
Is the fuse blown-out? Replace fuse. Repairopen circuit
in harness
between main fan
relay and ignition
switch.
10 CHECK MAIN FAN RELAY.
1)Turn ignition switch to OFF.
2)Remove main fan relay.
3)Measure resistance of main fan relay.
Terminal
No. 26 —No. 25:
Is the resistance more than 1
MΩ?Go to step 11. Replace main fan relay.
11 CHECK MAIN FAN RELAY.
1)Connect battery to terminals No. 27 and No.
28 of main fan relay.
2)Measure resistance of main fan relay.
Terminal
No. 26 —No. 25:
Is the resistance less than 1
Ω?Go to step 12. Replace main fan
relay.
12 CHECK HARNESS BETWEEN MAIN FAN
RELAY TERMINAL AND MAIN FAN MOTOR
CONNECTOR.
Measure resistance of harness between main
fan motor connector and main fan relay termi-
nal.
Connector & terminal
(F17) No. 2 —(F66) No. 25:
Is the resistance less than 1
Ω?Go to step 13. Repairopencircuit
in harness
between main fan
motor connector
and main fan relay
terminal.
13 CHECK HARNESS BETWEEN MAIN FAN
RELAY AND ECM.
1)Turn ignition switch to OFF.
2)Disconnect connector from ECM.
3)Measure resistance of harness between
main fan relay connector and ECM connector.
Connector & terminal
(F66) No. 27 —(B134) No. 3:
Is the resistance less than 1
Ω?Go to step 14. Repairopencircuit
in harness
between main fan
relay and ECM.
14 CHECK POOR CONTACT.
Check poor contact in connector between main
fan and ECM.
Is there poor contact in con-
nector between main fan motor
and ECM?
Repair poor con-
tact connector. Contact with your Subaru distributor.
Step Check Yes No

CO-13
COOLING
RADIATOR MAIN FAN SYSTEM
2. TURBO MODEL
DETECTING CONDITION:
Condition:
•Engine coolant temperature is above 96°C
(205°F).
•A/C compressor is rotated.
•Vehicle speed is below 19 km/h (12 MPH).
TROUBLE SYMPTOM:
•Radiator main fan does not rotate under the
above conditions.
•Radiator main fan does not rotate at high speed
when the following conditions are both met:
(1) Engine coolant temperature is above 90°C
(194°F)
(2) A/C is ON
Step Check Yes No
1 CHECK OPERATION OF RADIATOR.
1)Run the engine at idle. (Vehicle stationary)
2)Turn the A/C switch to OFF.
3)Warm the engine coolant temperature over
96°C (205°F).
Does the main radiator fan
rotate? Go to step 2. Go to step 3.
2 CHECK OPERATION OF RADIATOR.
1)Turn the A/C switch ON at condition of step
1.
Does the main radiator fan
rotate faster when A/C com-
pressor is operated?
Radiator main fan
system is okay. Go to step 17.
3 CHECK POWER SUPPLY TO MAIN FAN MO-
TOR.
CAUTION:
Be careful not to overheat engine during re-
pair.
1)Turn ignition switch to OFF.
2)Disconnect connector from main fan motor.
3)Start the engine, and warm it up until engine
coolant temperature increases over 96°C
(205°F).
4)Stop the engine and turn ignition switch to
ON.
5)Measure voltage between main fan motor
connector and chassis ground.
Connector & terminal
(F17) No. 3 (+) —Chassis ground (
−
−−
−
):
Is the voltage more than 10 V? Go to step 4. Go to step 7.
4 CHECK GROUND CIRCUIT OF MAIN FAN
MOTOR.
1)Turn ignition switch to OFF.
2)Measure 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 5. Repairopencircuit
in harness
between main fan
motor connector
and chassis
ground.
5 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 6.
6 CHECK MAIN FAN MOTOR.
Connect battery positive (+) terminal to termi-
nal No. 3, and negative (−) terminal to terminal
No. 1 of main fan motor connector.
Does the main fan rotate? Repair poor con-
tact in main fan
motor connector.
Replace main fan
motor with a new
one.
7 CHECK POWER SUPPLY TO MAIN FAN
RELAY1.
1)Turn ignition switch to OFF.
2)Remove main fan relay1 from A/C relay
holder.
3)Measure voltage between main fan relay1
terminal and chassis ground.
Connector & terminal
(F66) No. 26 (+) —Chassis ground (
−
−−
−
):
Is the voltage more than 10 V? Go to step 8. Go to step 9.

CO-14
COOLING RADIATOR MAIN FAN SYSTEM
8 CHECK POWER SUPPLY TO MAIN FAN
RELAY1.
1)Turn ignition switch to ON.
2)Measure voltage between main fan relay1
terminal and chassis ground.
Connector & terminal
(F66) No. 27 (+) —Chassis ground (
−
−−
− ):
Is the voltage more than 10 V? Go to step 12. Go to step 11.
9 CHECK 30 A FUSE.
1)Remove 30 A fuse from A/C relay holder.
2)Check condition of fuse.
Is the fuse blown-out? Replace fuse. Go to step 10.
10 CHECK POWER SUPPLY TO A/C RELAY
HOLDER 30 A FUSE TERMINAL.
Measure voltage of harness between A/C relay
holder 30 A fuse terminal and chassis ground.
Connector & terminal
(F27) No. 1 (+) —Chassis ground ( −
−−
− ):
Is the voltage more than 10 V? Repairopencircuit
in harness
between 30 A fuse
and main fan relay
terminal.
Repairopencircuit
in harness
betweenmainfuse
box connector and
30 A fuse terminal.
11 CHECK FUSE.
1)Turn ignition switch to OFF.
2)Remove fuse No. 18 from joint box.
3)Check condition of fuse.
Is the fuse blown-out? Replace fuse. Repairopen circuit
in harness
between main fan
relay and ignition
switch.
12 CHECK MAIN FAN RELAY.
1)Turn ignition switch to OFF.
2)Remove main fan relay1.
3)Measure resistance of main fan relay1.
Terminal
No. 26 —No. 25:
Is the resistance more than 1
MΩ?Go to step 13. Replace main fan relay.
13 CHECK MAIN FAN RELAY.
1)Connect battery to terminals No. 27 and No.
28 of main fan relay1.
2)Measure resistance of main fan relay1.
Terminal
No. 26 —No. 25:
Is the resistance less than 1
Ω?Go to step 14. Replace main fan
relay.
14 CHECK HARNESS BETWEEN MAIN FAN
RELAY TERMINAL AND MAIN FAN MOTOR
CONNECTOR.
Measure resistance of harness between main
fan motor connector and main fan relay termi-
nal.
Connector & terminal
(F17) No. 3 —(F66) No. 25:
Is the resistance less than 1
Ω?Go to step 15. Repairopencircuit
in harness
between main fan
motor connector
and main fan relay
terminal.
15 CHECK HARNESS BETWEEN MAIN FAN
RELAY AND ECM.
1)Turn ignition switch to OFF.
2)Disconnect connector from ECM.
3)Measure resistance of harness between
main fan relay connector and ECM connector.
Connector & terminal
(F66) No. 28 —(B137) No. 17:
Is the resistance less than 1
Ω?Go to step 16. Repairopencircuit
in harness
between main fan
relay and ECM.
16 CHECK POOR CONTACT.
Check poor contact in connector between main
fan and ECM.
Is there poor contact in con-
nector between main fan motor
and ECM?
Repair poor con-
tact connector. Contact with your Subaru distributor.
Step Check Yes No

CO-15
COOLING
RADIATOR MAIN FAN SYSTEM
17 CHECK POWER SUPPLY TO MAIN FAN MO-
TOR.
CAUTION:
Be careful not to overheat engine during re-
pair.
1)Turn ignition switch to OFF.
2)Disconnect connector from main fan motor.
3)Start the engine, and warm it up until engine
coolant temperature increases over 96°C
(205°F).
4)Turn the A/C switch ON.
5)Measure voltage while A/C compressor is
rotating.
6)Measure voltage between main fan motor
connector and chassis ground.
Connector & terminal
(F17) No. 2 (+) —Chassis ground (
−
−−
− ):
Is the voltage more than 10 V? Go to step 18. Go to step 20.
18 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 19.
19 CHECK MAIN FAN MOTOR.
Connect battery positive (+) terminal to termi-
nal No. 2, and negative (−) terminal to terminal
No. 1 of main fan motor connector.
Does the main fan rotate? Repair poor con-
tact in main fan
motor connector.
Replace main fan
motor with a new
one.
20 CHECK POWER SUPPLY TO MAIN FAN
RELAY2.
1)Turn ignition switch to OFF.
2)Remove main fan relay2 from A/C relay
holder.
3)Measure voltage between main fan relay2
terminal and chassis ground.
Connector & terminal
(F30) No. 23 (+) —Chassis ground ( −
−−
− ):
Is the voltage more than 10 V? Go to step 21. Go to step 22.
21 CHECK POWER SUPPLY TO MAIN FAN
RELAY2.
1)Turn ignition switch to ON.
2)Measure voltage between main fan relay2
terminal and chassis ground.
Connector & terminal
(F30) No. 22 (+) —Chassis ground ( −
−−
− ):
Is the voltage more than 10 V? Go to step 25. Go to step 24.
22 CHECK 30 A FUSE.
1)Remove 30 A fuse from A/C relay holder.
2)Check condition of fuse.
Is the fuse blown-out? Replace fuse. Go to step 23.
23 CHECK POWER SUPPLY TO A/C RELAY
HOLDER 30 A FUSE TERMINAL.
Measure voltage of harness between A/C relay
holder 30 A fuse terminal and chassis ground.
Connector & terminal
(F27) No. 1 (+) —Chassis ground ( −
−−
− ):
Is the voltage more than 10 V? Repairopencircuit
in harness
between 30 A fuse
and main fan relay
terminal.
Repairopencircuit
in harness
betweenmainfuse
box connector and
30 A fuse terminal.
24 CHECK FUSE.
1)Turn ignition switch to OFF.
2)Remove fuse No. 18 from joint box.
3)Check condition of fuse.
Is the fuse blown-out? Replace fuse. Repairopen circuit
in harness
between main fan
relay and ignition
switch.
Step Check Yes No

CO-16
COOLING RADIATOR MAIN FAN SYSTEM
NOTE:
Inspection by your Subaru distributor is required,
because probable cause is deterioration of multiple
parts.
25 CHECK MAIN FAN RELAY.
1)Turn ignition switch to OFF.
2)Remove main fan relay2.
3)Measure resistance of main fan relay2.
Terminal
No. 23 —No. 24:
Is the resistance more than 1
MΩ?Go to step 26. Replace main fan relay.
26 CHECK MAIN FAN RELAY.
1)Connect battery to terminals No. 21 and No.
22 of main fan relay1.
2)Measure resistance of main fan relay2.
Terminal
No. 23 —No. 24:
Is the resistance less than 1
Ω?Go to step 27. Replace main fan
relay.
27 CHECK HARNESS BETWEEN MAIN FAN
RELAY TERMINAL AND MAIN FAN MOTOR
CONNECTOR.
Measure resistance of harness between main
fan motor connector and main fan relay termi-
nal.
Connector & terminal
(F17) No. 2 —(F66) No. 24:
Is the resistance less than 1
Ω?Go to step 28. Repairopencircuit
in harness
between main fan
motor connector
and main fan relay
terminal.
28 CHECK HARNESS BETWEEN MAIN FAN
RELAY AND ECM.
1)Turn ignition switch to OFF.
2)Disconnect connector from ECM.
3)Measure resistance of harness between
main fan relay connector and ECM connector.
Connector & terminal
(F30) No. 21 —(B134) No. 28:
Is the resistance less than 1
Ω?Go to step 29. Repairopencircuit
in harness
between main fan
relay and ECM.
29 CHECK POOR CONTACT.
Check poor contact in connector between main
fan and ECM.
Is there poor contact in con-
nector between main fan motor
and ECM?
Repair poor con-
tact connector. Contact with your Subaru distributor.
Step Check Yes No

CO-17
COOLING
RADIATOR SUB FAN SYSTEM
3. Radiator Sub Fan System
A: SCHEMATIC
1. NON-TURBO MODEL
BATTERY SBF-1 No.3
No.17
No.18
SBF-4
B72 IGNITION
SWITCH
F27 20A
AIR CONDITIONING
RELAY HOLDER
F29 SUB
FAN
RELAY
SUB FAN
MOTOR
3
4
18
20
19
17
F16
2
1
F27 20A
AIR CONDITIONING
RELAY HOLDER
F66 MAIN
FAN
RELAY
MAIN FAN
MOTOR
1
2
26
28
27
25
F17
2
1
2 1
B134 ECM
F45
B62
12
3
LHD :2
RHD :7
LHD :12
RHD :17
1
2
F17
2 1
F16
F67
F27 F28
1 2
3 4
5 6
7
8
9
10
11 12
13 14
15
16
17
18
19 20
21 22
23
24
25
26
27 28
29
30
F31
F29 F66
F30
B134
1 2 3 4 5 6 7 8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
24 25 26 27 28 29 30 31 32 33 34 35
F45
3412 89
10 11
12 13 14 15 16 17 18 19 20 21 22 23 24
567
F45
1234 56789
10 11 12 13 14 15 16 17 18 19 20
LHD: RHD:
EN0880

CO-18
COOLING RADIATOR SUB FAN SYSTEM
2. TURBO MODEL
EN0260
No.18
No.17
E E
IGNITION
SWITCH
SBF-4
SBF-1
B62
B72
F45
SUB FAN
RELAY2
30A
F16
B137 ECM 17
28
BATTERY
F17
F29
F29
B72 (BLUE)
(LHD)
(RHD)
F27
F27 F45 F16
F17
SUB FAN
RELAY1
F28
F28
MAIN FAN
RELAY2
AIR CONDITIONING RELAY HOLDER
F30
F30 F66 B137
MAIN FAN
RELAY1
F66
30A
34
12 1 2
3 4
5 6
7
8
9
10
11 12
13 14
15
16
17
18
19 20
21 22
23
24
25
26
27 28
29
30
12 78956 34
10 11 12 19 20 21
29 30 31
13 14 15 16 17
27 28 18 22 23 24 25 26
3412 89 10 11
12 13 14 15 16 17 18 19 20 21 22 23 24
567
1 3 2
SUB FAN
MOTOR
M
1 3 2
MAIN FAN
MOTOR
M
17 19 20 18 24 22 21 23 25 27 28 26
6 5 7 2 1 4 3 8
2
1
*
*
1
23
1234 56
9
10 11 12 13 14
7
15 18
8
16 17
LHD : 2
RHD : 7
LHD : 12
RHD : 17
*1
*2

CO-19
COOLING
RADIATOR SUB FAN SYSTEM
B: INSPECTION
1. NON-TURBO MODEL
NOTE:
System for A/C equipped vehicles only.
DETECTING CONDITION:
Condition (1):
•Engine coolant temperature is below 95°C
(203°F).
•A/C switch is turned ON.
•Vehicle speed is below 19 km/h (12 MPH).
Condition (2):
•Engine coolant temperature is above 100°C
(212°F).
•A/C switch is turned OFF.
•Vehicle speed is below 19 km/h (12 MPH).
TROUBLE SYMPTOM:
•Radiator sub fan does not rotate under condi-
tions (1) and (2) above.
Step Check Yes No
1 CHECK POWER SUPPLY TO SUB FAN MO-
TOR.
CAUTION:
Be careful not to overheat engine during re-
pair.
1)Turn ignition switch to OFF.
2)Disconnect connector from sub fan motor
and main fan motor.
3)Start the engine, and warm it up until engine
coolant temperature increases over 100°C
(212°F).
4)Stop the engine and turn ignition switch to
ON.
5)Measure voltage between sub fan motor
connector and chassis ground.
Connector & terminal
(F16) No. 2 (+) —Chassis ground (
−
−−
−
):
Is the voltage more than 10 V? Go to step 2. Go to step 5.
2 CHECK GROUND CIRCUIT OF SUB FAN
MOTOR.
1)Turn ignition switch to OFF.
2)Measure resistance between sub fan motor
connector and chassis ground.
Connector & terminal
(F16) No. 1 —Chassis ground:
Is the resistance less than 5
Ω?Go to step 3. Repairopencircuit
in harness
between sub fan
motor connector
and chassis
ground.
3 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 4.
4 CHECK SUB FAN MOTOR.
Connect battery positive (+) terminal to termi-
nal No. 2, and negative (−) terminal to terminal
No. 1 of sub fan motor connector.
Does the sub fan rotate? Repair poor con-
tact in sub fan
motor connector.
Replace sub fan
motor with a new
one.
5 CHECK POWER SUPPLY TO SUB FAN RE-
LAY.
1)Turn ignition switch to OFF.
2)Remove sub fan relay from A/C relay holder.
3)Measure voltage between sub fan relay ter-
minal and chassis ground.
Connector & terminal
(F28) No. 18 (+) —Chassis ground (
−
−−
−
):
Is the voltage more than 10 V? Go to step 6. Go to step 7.
6 CHECK POWER SUPPLY TO SUB FAN RE-
LAY.
1)Turn ignition switch to ON.
2)Measure voltage between sub fan relay ter-
minal and chassis ground.
Connector & terminal
(F28) No. 20 (+) —Chassis ground (
−
−−
−
):
Is the voltage more than 10 V? Go to step 10. Go to step 9.