SUBARU LEGACY 1997 Service Repair Manual

2. Radiator Main Fan
B2M1306
21
2-5DIAGNOSTICS
2. Radiator Main Fan

A: OPERATION (WITHOUT A/C MODEL)
CONDITION:
Engine coolant temperature is above 95°C (203°F).
TROUBLE SYMPTOM:
Radiator main fan does not operate under the above
condition.
1. Check fuse and power supply.
OK
Not OK
Melted fuse,repair the shorted part of the circuit
,replace fuse.
2. Check harness connector between fuse and
relay box, and A/C relay holder.
OK
Not OK
Repair or replace wiring harness.
3. Check A/C relay holder.
OK
Not OK
Repair or replace A/C relay holder.
4. Check harness connector between A/C relay
holder and main fan motor.
OK
Not OK
Repair or replace wiring harness.
5. Check ground circuit of main fan motor.
OK
Not OK
Repair or replace wiring harness.
6. Check main fan motor.
OK
Not OK
Replace main fan motor.
Refer to 2-7 On-Board Diagnostics II System.
B2M0427A
1. CHECK FUSE AND POWER SUPPLY.
1) Check fuse No. 13.
2) Turn ignition switch to ACC.
3) Measure voltage between fuse and relay box, and body.
Connector & terminal / Specified voltage:
(F40) No. 3—Body / 10 V, or more






22
2-5DIAGNOSTICS
2. Radiator Main Fan

B2M0325A
2. CHECK HARNESS CONNECTOR BETWEEN FUSE
AND RELAY BOX, AND A/C RELAY HOLDER.
1) Turn ignition switch to OFF.
2) Disconnect connectors from fuse and relay box, and
A/C relay holder.
3) Measure resistance of harness connector between fuse
and relay box, and A/C relay holder.
Connector & terminal / Specified resistance:
(F40) No. 3—(F29) No. 2 / 10Ω, max.
B2M0428A
3. CHECK A/C RELAY HOLDER.
1) Disconnect connector from A/C relay holder.
2) Measure resistance between terminals of A/C relay
holder.
Connector & terminal / Specified resistance:
(F29) No. 2—(F28) No. 4 / 10Ω, max.
(F29) No. 2—(F30) No. 4 / 10Ω, max.
B2M0366A
4. CHECK HARNESS CONNECTOR BETWEEN A/C
RELAY HOLDER AND MAIN FAN MOTOR.
1) Disconnect connectors from A/C relay holder and main
fan motor.
2) Measure resistance of harness connector between A/C
relay holder and main fan motor.
Connector & terminal / Specified resistance:
(F28) No. 4—(F17) No. 2 / 10Ω, max.
(F30) No. 4—(F17) No. 3 / 10Ω, max.
B2M0367A
5. CHECK GROUND CIRCUIT OF MAIN FAN MOTOR.
Measure resistance between main fan motor connector
and body.
Connector & terminal / Specified resistance:
(F17) No. 1—Body / 10Ω, max.
B2M0368A
6. CHECK MAIN FAN MOTOR.
1) Disconnect connector from main fan motor.
2) Connect battery positive (+) terminal to terminals No. 2
and No. 3, and connect terminal No. 1 to ground. Ensure
that fan rotates.
23
2-5DIAGNOSTICS
2. Radiator Main Fan

B: LO MODE OPERATION (WITH A/C MODEL)
CONDITION:
Condition (1) :
Engine coolant temperature is below 89°C (192°F).
A/C switch is turned ON.
Vehicle speed is below 10 km/h (6 MPH).
Condition (2) :
Engine coolant temperature is above 95°C (203°F).
A/C switch is turned OFF.
Vehicle speed is below 10 km/h (6 MPH).
TROUBLE SYMPTOM:
Radiator main fan does not rotate at LO speed under
conditions (1) and (2) above.
1. Check power supply to main fan relay-1.
OK
Not OK
Melted fuse (in A/C relay holder),repair the
shorted part of the circuit,replace fuse.
2. Check main fan relay-1.
OK
Not OK
Replace main fan relay-1.
3. Check harness connector between main fan
relay-1 and main fan motor.
OK
Not OK
Repair or replace wiring harness.
4. Check ground circuit of main fan motor.
OK
Not OK
Repair or replace wiring harness.
5. Check main fan motor.
OK
Not OK
Replace main fan motor.
Refer to 2-7 On-Board Diagnostics II System.





24
2-5DIAGNOSTICS
2. Radiator Main Fan

B2M0369A
1. CHECK POWER SUPPLY TO MAIN FAN RELAY-1.
1) Turn ignition switch to OFF.
2) Disconnect connector from A/C relay holder.
3) Measure voltage between A/C relay holder connector
and body.
Connector & terminal / Specified voltage:
(F28) No. 2—Body / 10 V, or more
(F28) No. 1—Body / 1 V, max.
4) Turn ignition switch to ON.
5) Measure voltage between A/C relay holder connector
and body.
Connector & terminal / Specified voltage:
(F28) No. 1—Body / 10 V, or more
B2M0370A
2. CHECK MAIN FAN RELAY-1.
1) Turn ignition switch to OFF.
2) Remove main fan relay-1 from A/C relay holder.
3) Check continuity between terminals (indicated in table
below) when terminal (1) is connected to battery and ter-
minal (3) is grounded.
When current flows.Between terminals (2)
and (4)Continuity exists.
When current does not
flow.Between terminals (2)
and (4)Continuity does not
exist.
Between terminals (1)
and (3)Continuity exists.
B2M0371A
3. CHECK HARNESS CONNECTOR BETWEEN MAIN
FAN RELAY-1 AND MAIN FAN MOTOR.
1) Disconnect connectors from main fan relay-1 and main
fan motor.
2) Measure resistance of harness connector between
main fan relay-1 and main fan motor.
Connector & terminal / Specified resistance:
(F28) No. 4—(F17) No.2 / 10Ω, max.
25
2-5DIAGNOSTICS
2. Radiator Main Fan

B2M0367A
4. CHECK GROUND CIRCUIT OF MAIN FAN MOTOR.
Measure resistance between main fan motor connector
and body.
Connector & terminal / Specified resistance:
(F17) No. 1—Body / 10Ω, max.
B2M0372A
5. CHECK MAIN FAN MOTOR.
1) Disconnect connector from main fan motor.
2) Connect battery positive (+) terminal to terminal No. 2
and connect terminal No. 1 to ground. Ensure that fan
rotates at LO speed.
26
2-5DIAGNOSTICS
2. Radiator Main Fan

C: HI MODE OPERATION (WITH A/C MODEL)
CONDITION:
Condition (1) :
Engine coolant temperature is below 89°C (192°F).
A/C switch is turned ON.
Vehicle speed is over 20 km/h (12 MPH).
Condition (2) :
Engine coolant temperature is above 95°C (203°F).
A/C switch is turned OFF.
Vehicle speed is over 20 km/h (12 MPH).
Condition (3) :
Engine coolant temperature is above 95°C (203°F).
A/C switch is turned ON.
TROUBLE SYMPTOM:
Radiator main fan does not rotate at HI speed under
conditions (1), (2) and (3) above.
1. Check operation of main fan motor LO mode.
OK
Not OK
Check LO mode operation.
2. Check power supply to main fan relay-2.
OK
Not OK
Melted fuse (in A/C relay holder),repair the
shorted part of the circuit,replace fuse.
3. Check main fan relay-2.
OK
Not OK
Replace main fan relay-2.
4. Check harness connector between main fan
relay-2 and main fan motor.
OK
Not OK
Repair or replace wiring harness.
5. Check ground circuit of main fan motor.
OK
Not OK
Repair or replace wiring harness.
6. Check main fan motor.
OK
Not OK
Replace main fan motor.
Refer to 2-7 On-Board Diagnostics II System.






27
2-5DIAGNOSTICS
2. Radiator Main Fan

1. CHECK OPERATION OF MAIN FAN MOTOR LO
MODE.
Check that radiator main fan rotates at LO speed under
each condition described under LO mode operation. to 2-5 [K2B0].>
B2M0374A
2. CHECK POWER SUPPLY TO MAIN FAN RELAY-2.
1) Turn ignition switch to OFF.
2) Disconnect connector from A/C relay holder.
3) Measure voltage between A/C relay holder connector
and body.
Connector & terminal / Specified voltage:
(F30) No. 2—Body / 10 V, or more
(F30) No. 1—Body / 1 V, max.
4) Turn ignition switch to ON.
5) Measure voltage between A/C relay holder connector
and body.
Connector & terminal / Specified voltage:
(F30) No. 1—Body / 10 V, or more
B2M0370A
3. CHECK MAIN FAN RELAY-2.
1) Turn ignition switch to OFF.
2) Remove main fan relay-2 from A/C relay holder.
3) Check continuity between terminals (indicated in table
below) when terminal (1) is connected to battery and ter-
minal (3) is grounded.
When current flows.Between terminals (2)
and (4)Continuity exists.
When current does not
flow.Between terminals (2)
and (4)Continuity does not
exist.
Between terminals (1)
and (3)Continuity exists.
28
2-5DIAGNOSTICS
2. Radiator Main Fan

B2M0375A
4. CHECK HARNESS CONNECTOR BETWEEN MAIN
FAN RELAY-2 AND MAIN FAN MOTOR.
1) Disconnect connectors from main fan relay-2 and main
fan motor.
2) Measure resistance of harness connector between
main fan relay-2 and main fan motor.
Connector & terminal / Specified resistance:
(F30) No. 4—(F17) No. 3 / 10Ω, max.
B2M0367A
5. CHECK GROUND CIRCUIT OF MAIN FAN MOTOR.
Measure resistance between main fan motor connector
and body.
Connector & terminal / Specified resistance:
(F17) No. 1—Body / 10Ω, max.
B2M0368A
6. CHECK MAIN FAN MOTOR.
1) Disconnect connector from main fan motor.
2) Connect battery positive (+) terminal to terminals No. 2
and No. 3, and connect terminal No. 1 to ground. Ensure
that fan rotates at HI speed.
29
2-5DIAGNOSTICS
2. Radiator Main Fan

1. Intake Manifold
1. 2200 cc MODEL
B2M1031A
2
2-7COMPONENT PARTS
1. Intake Manifold