1997 SUBARU LEGACY check engine

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

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.
30
2-7SERVICE PROCEDURE
12. Idle Air Control Solenoid Valve - 13. Pressure Sources Switching Solenoid Valve (AT model)

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.
30
2-7SERVICE PROCEDURE
12. Idle Air Control Solenoid Valve - 13. Pressure Sources Switching Solenoid Valve (AT model)

B2M0049
11) On AWD model, after removing fuel sub meter unit,
drain fuel from there.
WARNING:
Do not use a motor pump when draining fuel.
2. On-Car Services
A: MEASUREMENT OF FUEL PRESSURE
1) Release fuel pressure.
2) Connect connector to fuel pump.
G2M0347
3) Disconnect fuel delivery hoses from fuel filter, and con-
nect fuel pressure gauge.
G2M0348
4) Start the engine.
5) Measure fuel pressure while disconnecting pressure
regulator vacuum hose from collector chamber.
Fuel pressure:
235 — 265 kPa (2.4 — 2.7 kg/cm
2, 34 — 38 psi)
6) After connecting pressure regulator vacuum hose, mea-
sure fuel pressure.
Fuel pressure:
177 — 206 kPa (1.8 — 2.1 kg/cm
2, 26 — 30 psi)
WARNING:
Before removing fuel pressure gauge, release fuel
pressure.
NOTE:
If out of specification as measured at step 6), check or
replace pressure regulator and pressure regulator vacuum
hose.
12
2-8SERVICE PROCEDURE
1. Precautions - 2. On-Car Services

B2M0049
11) On AWD model, after removing fuel sub meter unit,
drain fuel from there.
WARNING:
Do not use a motor pump when draining fuel.
2. On-Car Services
A: MEASUREMENT OF FUEL PRESSURE
1) Release fuel pressure.
2) Connect connector to fuel pump.
G2M0347
3) Disconnect fuel delivery hoses from fuel filter, and con-
nect fuel pressure gauge.
G2M0348
4) Start the engine.
5) Measure fuel pressure while disconnecting pressure
regulator vacuum hose from collector chamber.
Fuel pressure:
235 — 265 kPa (2.4 — 2.7 kg/cm
2, 34 — 38 psi)
6) After connecting pressure regulator vacuum hose, mea-
sure fuel pressure.
Fuel pressure:
177 — 206 kPa (1.8 — 2.1 kg/cm
2, 26 — 30 psi)
WARNING:
Before removing fuel pressure gauge, release fuel
pressure.
NOTE:
If out of specification as measured at step 6), check or
replace pressure regulator and pressure regulator vacuum
hose.
12
2-8SERVICE PROCEDURE
1. Precautions - 2. On-Car Services

B2M0329A
2) Hardened facing
Correct by using emery paper or replace.
3) Oil soakage on facing
Replace clutch disc and inspect transmission front oil seal,
transmission case mating surface, engine rear oil seal and
other points for oil leakage.
B2M0330A
4) Deflection on facing
If deflection exceeds the specified value at the outer cir-
cumference of facing, repair or replace.
Limit for deflection:
1.0 mm (0.039 in) at R = 107 mm (4.21 in)
B2M0333A
5) Worn spline, loose rivets and torsion spring failure
Replace defective parts.
G2M0248
2. CLUTCH COVER
Visually check for the following items without
disassembling, and replace or repair if defective.
1) Loose thrust rivet.
2) Damaged or worn bearing contact area at center of
diaphragm spring.
G2M0249
3) Damaged or worn disc contact surface of pressure
plate.
4) Loose strap plate setting bolt.
5) Worn diaphragm sliding surface.
13
2-10SERVICE PROCEDURE
4. Clutch Disc and Cover