1996 SUBARU LEGACY air condition

If noise still exists, conduct diagnostics procedures in
accordance with the following table.
CAUTION:
Do not disconnect spark plug cord while engine is run-
ning.
Type of sound Condition Possible cause
Regular clicking soundSound increases as engine
speed increases.Valve mechanism is defective.
Broken lash adjuster
Worn camshaft
Broken valve spring
Worn valve lifter hole
Heavy and dull clankOil pressure is low.Worn crankshaft main bearing
Worn connecting rod bearing (big end)
Oil pressure is normal.Loose flywheel mounting bolts
Damaged engine mounting
High-pitched clank
(Spark knock)Sound is noticeable when
accelerating with an overload.Ignition timing advanced
Accumulation of carbon inside combustion chamber
Wrong spark plug
Improper gasoline
Clank when engine speed is
medium (1,000 to 2,000 rpm).Sound is reduced when fuel
injector connector of noisy
cylinder is disconnected.
(NOTE*)Worn crankshaft main bearing
Worn bearing at crankshaft end of connecting rod
Knocking sound when engine
is operating under idling speed
and engine is warm.Sound is reduced when fuel
injector connector of noisy
cylinder is disconnected.
(NOTE*)Worn cylinder liner and piston ring
Broken or stuck piston ring
Worn piston pin and hole at piston end of connecting rod
Sound is not reduced if each
fuel injector connector is
disconnected in turn. (NOTE*)Unusually worn valve lifter
Worn cam gear
Worn camshaft journal bore in crankcase
Squeaky sound—Insufficient generator lubrication
Rubbing sound—Defective generator brush and rotor contact
Gear scream when starting
engine—Defective ignition starter switch
Worn gear and starter pinion
Sound like polishing glass with
a dry cloth—Loose drive belt
Defective engine coolant pump shaft
Hissing sound—Loss of compression
Air leakage in air intake system, hoses, connections or
manifolds
Timing belt noise—Loose timing belt
Belt contacting case/adjacent part
NOTE*:
When disconnecting fuel injector connector, Malfunction Indicator Light (CHECK ENGINE light) illuminates and trouble code is stored in
ECM memory.
Therefore, carry out the CLEAR MEMORY MODE and INSPECTION MODE after connecting fuel injector connector. (Ref. to 2-7 On-Board
Diagnostics II System.)
79
2-3bDIAGNOSTICS
2. Engine Noise

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

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

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

A: LO MODE OPERATION
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 sub fan does not rotate at LO speed under
conditions (1) and (2) above.
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 sub fan motor.
OK
Not OK
Repair or replace wiring harness.
3. Check ground circuit of sub fan motor.
OK
Not OK
Repair or replace wiring harness.
4. Check sub fan motor.
OK
Not OK
Replace sub fan motor.
Refer to 2-7 On-Board Diagnostics II System.




31
2-5DIAGNOSTICS
3. Radiator Sub Fan (With A/C model only)

B: HI MODE OPERATION
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 sub fan does not rotate at HI speed under con-
ditions (1), (2) and (3) above.
1. Check operation of sub fan motor LO mode.
OK
Not OK
Check LO mode operation.
2. Check power supply to sub fan relay-2.
OK
Not OK
Melted fuse (in A/C relay holder),repair the
shorted part of the circuit,replace fuse.
3. Check sub fan relay-2.
OK
Not OK
Replace sub fan relay-2.
4. Check harness connector between sub fan
relay-2 and sub fan motor.
OK
Not OK
Repair or replace wiring harness.
5. Check ground circuit of sub fan motor.
OK
Not OK
Repair or replace wiring harness.
6. Check sub fan motor.
OK
Not OK
Replace sub fan motor.
Refer to 2-7 On-Board Diagnostics II System.






33
2-5DIAGNOSTICS
3. Radiator Sub Fan (With A/C model only)

B2M0358
4) Slowly pour one can (16 oz) of cleaner into by-pass air
hole.
Cleaner:
Part No. 1050002 GM Top Engine Cleaner
Part No. X66-A AC Delco Carburetor Tune-up
Conditioner
5) Leave the engine running for five minutes.
NOTE:
White smoke comes out of the muffler until the cleaner is
used up.
6) Stop the engine.
B2M0359
7) Release the throttle valve.
8) Connect by-pass hose to idle air control solenoid valve.
G2M0096
9) Check duty ratio of idle air control solenoid valve with
Subaru Select Monitor.
(1) Connect Subaru Select Monitor to the data link con-
nector.
(2) Start the engine and turn Subaru Select Monitor
switch to ON.
(3) Select mode“F12”.
(4) Make sure duty ratio on radiator fan and electric
load is OFF.
Specified data: 25—40%
B2M0361
13. Pressure Sources Switching
Solenoid Valve (AT model)
A: REMOVAL AND INSTALLATION
1) Disconnect connector from pressure sources switching
solenoid valve.
2) Disconnect hoses from pressure sources switching
solenoid valve.
27
2-7SERVICE PROCEDURE
12. Idle Air Control Solenoid Valve - 13. Pressure Sources Switching Solenoid Valve (AT model)

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