Subaru LEGACY 2003 Service Manual page 13

B: INSPECTION
NOTE:
Radiator sub fan system is for model with A/C.
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 conditions (1) and (2) above.
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 ( − − − − ):
Does the measured value exceed the spec-
ified value?
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 measured value less than the speci-
fied valve?
3 CHECK POOR CONTACT.
Check poor contact in sub fan motor connec-
tor.
Is there poor contact in sub fan motor connec-
tor?
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?
RADIATOR SUB FAN SYSTEM
Step Value
10 V
5 Ω
Sub fan rotates.
CO(H4SO)-11
Yes
Go to step 2. Go to step 5.
Go to step 3. Repair open circuit
in harness
between sub fan
motor connector
and chassis
ground.
Repair poor con- Go to step 4.
tact in sub fan
motor connector.
Repair poor con- Replace sub fan
tact in sub fan motor with a new
motor connector. one.
COOLING
No