check engine SUBARU FORESTER 2004 Service User Guide
[x] Cancel search | Manufacturer: SUBARU, Model Year: 2004, Model line: FORESTER, Model: SUBARU FORESTER 2004Pages: 2870, PDF Size: 38.67 MB
Page 75 of 2870

AC-19
HVAC SYSTEM (AUTO A/C)(DIAGNOSTIC)
Diagnostics for A/C System Malfunction
9 CHECK OPERATION OF MAIN FAN MOTOR.
1) Start the engine and turn the A/C switch to
ON.
2) Check the operation of main fan motor.Does the main fan motor oper-
ate normally?Go to step 14.Go to step 10.
10 CHECK POWER SUPPLY TO MAIN FAN MO-
TOR.
CAUTION:
Be careful not to overheat the engine during
repair.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from 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 the voltage between main fan
motor harness connector and chassis ground.
Connector & terminal
Except turbo AT model:
(F17) No. 2 (+) — Chassis ground (
−):
Turbo AT model:
(F17) No. 1 (+) — Chassis ground (
−):Is the voltage more than 10 V? Go to step 11.Repair the har-
ness for main fan
motor power sup-
ply circuit.
11 CHECK GROUND CIRCUIT OF MAIN FAN
MOTOR.
Measure the resistance between main fan
motor harness connector and chassis ground.
Connector & terminal
Except turbo AT model:
(F17) No. 1 — Chassis ground:
Turbo AT model:
(F17) No. 2 — Chassis ground:Is the resistance less than 1
Ω?Go to step 12.Repair the har-
ness for main fan
motor ground cir-
cuit.
12 CHECK MAIN FAN MOTOR.
Connect the battery positive (+) terminal to ter-
minal No. 2, and ground (−) terminal to termi-
nal No. 1 of main fan motor connector to make
sure that main fan motor rotate.Does the main fan rotate? Go to step 13.Replace the main
fan motor.
13 CHECK POOR CONTACT IN MAIN FAN MO-
TOR CONNECTOR.
Check poor contact in main fan motor harness
connector.Is there poor contact in con-
nector?Go to step 14.Repair the poor
contact in main fan
motor connector.
14 CHECK OPERATION OF SUB FAN MOTOR.
1) Start the engine and turn the A/C switch to
ON.
2) Check the operation of sub fan motor.Does the sub fan motor oper-
ate normally?Go to step 19.Go to step 15. Step Check Yes No
Page 76 of 2870

AC-20
HVAC SYSTEM (AUTO A/C)(DIAGNOSTIC)
Diagnostics for A/C System Malfunction
15 CHECK POWER SUPPLY TO SUB FAN MO-
TOR.
CAUTION:
Be careful not to overheat the engine during
repair.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from sub 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 the voltage between sub fan
motor harness connector and chassis ground.
Connector & terminal
Except turbo AT model:
(F16) No. 2 (+) — Chassis ground (
−):
Turbo AT model:
(F16) No. 1 (+) — Chassis ground (
−):Is the voltage more than 10 V? Go to step 16.Repair the har-
ness for sub fan
motor power sup-
ply circuit.
16 CHECK GROUND CIRCUIT OF SUB FAN
MOTOR.
Measure the resistance between sub fan motor
harness connector and chassis ground.
Connector & terminal
Except turbo AT model:
(F16) No. 1 — Chassis ground:
Turbo AT model:
(F16) No. 2 — Chassis ground:Is the resistance less than 1
Ω?Go to step 17.Repair the har-
ness for sub fan
motor ground cir-
cuit.
17 CHECK SUB FAN MOTOR.
Connect the battery positive (+) terminal to ter-
minal No. 2, and ground (−) terminal to termi-
nal No. 1 of sub fan motor connector to make
sure that sub fan motor rotate.Does the sub fan motor rotate? Go to step 18.Replace the sub
fan motor.
18 CHECK POOR CONTACT IN SUB FAN MO-
TOR CONNECTOR.
Check poor contact in sub fan motor connec-
tor.Is there poor contact in con-
nector?Go to step 19.Repair the poor
contact in sub fan
motor connector.
19 CHECK POOR CONTACT IN AUTO A/C
CONTROL MODULE CONNECTOR.
Check poor contact in auto A/C control module
connector.Is there poor contact in con-
nector?Replace the auto
A/C control mod-
ule.Repair the con-
nector. Step Check Yes No
Page 140 of 2870

AB-8
AIRBAG SYSTEM (DIAGNOSTIC)
General Description
B: INSPECTION
Before diagnosing, check the following items that might be related to the engine problem:
1. BATTERY
Measure the battery voltage and specific gravity of electrolyte.
Standard voltage: 12 V
Specific gravity: Above 1.260
C: PREPARATION TOOL
1. SPECIAL TOOL
TEST HARNESS M
ILLUSTRATION TOOL NUMBER DESCRIPTION REMARKS
98299FE020 TEST HARNESS M Used when measuring voltage, resistance of
airbag system.
Used with test harness T (98299SA060).
5M3M 4M
1M
2M
ST98299FE020
AB-00425
5M
1
21
Lg
2
8
18
5
16
7
6
9
1
11
10
4
2
Lg
YL
Y
100
GW
3M 4M
1M
2M
12
65 21
4334 12
56 21 1
234 5678
91011
12 13 14 15 16 17 18
1
2
3
4
5
6
2M 1M 4M 3M
5M6
5
4
3
2
1
Page 183 of 2870

AB-51
AIRBAG SYSTEM (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step Check Yes No
1 CHECK DRIVERS AIRBAG MODULE.
1) Turn the ignition switch to OFF, disconnect
the battery ground cable, and wait more than
20 seconds.
2) Remove the driver’s airbag module.
3) Connect the connector (AB2) to connector
(1N) in test harness N.
4) Connect the airbag resistor to connector
(2N) in test harness N.
5) Connect the battery ground cable and turn
the ignition switch to ON.Is the airbag warning light
turned on normally?Replace the
driver’s airbag
module.
Airbag Module.>Go to step 2.
2 CHECK ROLL CONNECTOR.
1) Turn the ignition switch to OFF, disconnect
the battery ground cable, and wait more than
20 seconds.
2) Disconnect the test harness N from the
connector (AB2).
3) Remove the instrument panel lower cover
and disconnect the connector (AB21) from
(AB26).
4) Connect the connector (1F) in test harness
F to connector (AB21).
5) Connect the airbag resistor to connector
(3F) in test harness F.
6) Connect the battery ground cable and turn
the ignition switch to ON.Is the airbag warning light
turned on normally?Replace the roll
connector.
nector.>Go to step 3.
3 CHECK AIRBAG MAIN HARNESS.
1) Turn the ignition switch to OFF, disconnect
the battery ground cable, and wait more than
20 seconds.
2) Disconnect the airbag resistor from the
connector (3F) in test harness F.
3) Remove the glove box, and disconnect the
connectors (AB4) and passenger’s airbag
module (AB27).
4) Disconnect the connector (AB3) from the
airbag control module, and connect the con-
nector (1R) in test harness R.
5) Connect the battery ground cable and turn
the ignition switch to ON. (engine OFF)
6) Measure the voltage between connector
(2R) in test harness R and the chassis ground.
Connector & terminal
(2R) No. 2 (+) — Chassis ground (
−):
(2R) No. 4 (+) — Chassis ground (
−): Is the voltage less than 1 V? Replace the airbag
control module.
Module.>Replace the airbag
main harness with
body harness.
Page 243 of 2870

SB-9
SEAT BELT SYSTEM
Seat Belt Warning System
14 CHECK HARNESS BETWEEN TCU AND
SEAT BELT TIMER MODULE.
Measure the resistance between seat belt
timer module harness connector and chassis
ground.
Connector & terminal
(B44) No. 7 — Chassis ground:Is the resistance less than 10
Ω?Go to step 15.Repair the short of
harness.
15 CHECK SEAT BELT TIMER MODULE OUT-
PUT SIGNAL.
1) Turn the ignition switch to ON.
2) Measure the voltage between seat belt
timer module harness connector and chassis
ground.
Connector & terminal
(B44) No. 2 (+) — Chassis ground (–):Is the voltage more than 10 V? Go to step 16.Check the wiring
harness and com-
bination meter,
and then repair or
replace them.
16 CHECK POOR CONTACT.
Check the poor contact of seat belt warning
light circuit.Is there any poor contact
occurs?Repair the poor
contact.Go to step 17.
17 CHECK SEAT BELT TIMER MODULE.
1) Connect all connectors.
2) Lift-up the vehicle and place rigid racks.
NOTE:
Raise all wheels off floor.
3) Hold the tang plate disconnected from seat
belt buckle.
4) Start the engine, and set the vehicle speed
less than 19 km/h (12 MPH)
N
OTE:
The speed difference between front and rear
wheels may light the ABS warning light, but this
indicates no malfunction. When diagnosis is fin-
ished, perform the ABS memory clearance pro-
cedure of OBD system.
Check seat belt warning light comes on.Does the seat belt warning
light come on?Go to step 18.Replace the seat
belt timer module.
18 CHECK SEAT BELT TIMER MODULE.
1) Connect all connectors.
2) Lift-up the vehicle and place rigid racks.
N
OTE:
Raise all wheels off floor.
3) Hold the tang plate disconnected from seat
belt buckle.
4) Start the engine, and set the vehicle speed
more than 25 km/h (16 MPH).
NOTE:
The speed difference between front and rear
wheels may light the ABS warning light, but this
indicates no malfunction. When diagnosis is fin-
ished, perform the ABS memory clearance pro-
cedure of OBD system.
Check seat belt warning light comes on and
buzzer beeps.Does the seat belt warning
light come on and buzzer
beep?Temporary poor
contact of connec-
tor or harness may
be the cause.
Check the poor
contact.Replace the seat
belt timer module. Step Check Yes No
Page 313 of 2870

ET-3
ENTERTAINMENT
Radio System
2. Radio System
A: WIRING DIAGRAM
1. RADIO
B: INSPECTION
Symptom Repair order
No power coming in. (No display and no sound from speakers.) (1) Check the fuse and power supply for radio.
(2) Check the radio ground.
(3) Remove the radio for repair.
A specific speaker does not operate. (1) Check the speaker.
(2) Check the output circuit between radio and speaker.
Radio generates noise with engine running. (1) Check the radio ground.
(2) Check the generator.
(3) Check the ignition coil.
(4) Remove the radio for repair.
AM and FM modes are weak or noisy. (1) Check the antenna.
(2) Check the antenna amplifier.
(3) Check the noise suppressor.
(4) Check the radio ground.
(5) Remove the radio for repair.
Page 388 of 2870

IDI-4
INSTRUMENTATION/DRIVER INFO
Combination Meter System
B: INSPECTION
CAUTION:
When measuring voltage and resistance of the ECM, TCM, or each sensor, use a tapered pin with a
diameter of less than 0.64 mm (0.025 in) in order to avoid poor contact. Do not insert the pin more
than 2 mm (0.08 in).
1. SYMPTOM CHART
Symptom Repair order Reference
Combination meter assembly does not operate. (1) Power supply
(2) Ground circuit
GROUND CIRCUIT,
INSPECTION, Combi-
nation Meter System.>
Speedometer does not operate. (1) (MT model) Vehicle speed sensor
(AT model) TCM
(2) Harness
(3) SpeedometerMT model:
SPEED SENSOR,
INSPECTION, Combi-
nation Meter System.>
AT model:
SION CONTROL MOD-
ULE (TCM),
INSPECTION, Combi-
nation Meter System.>
Tachometer does not operate. (1) ECM
(2) Harness
(3) Tachometer
MODULE (ECM),
INSPECTION, Combi-
nation Meter System.>
Fuel gauge does not operate. (1) Fuel level sensor
(2) Harness
(3) Fuel gauge
SOR, INSPECTION,
Combination Meter
System.>
Water temperature gauge does not operate. (1) Engine coolant temperature sensor
(2) Harness
(3) Water temperature gauge
TEMPERATURE SEN-
SOR, INSPECTION,
Combination Meter
System.>
Outside temperature indicator does not operate. (1) Ambient sensor
(2) Harness
(3) Combination meter
TURE INDICATOR,
INSPECTION, Combi-
nation Meter System.>
Page 389 of 2870

IDI-5
INSTRUMENTATION/DRIVER INFO
Combination Meter System
2. CHECK POWER SUPPLY AND GROUND CIRCUIT
3. CHECK VEHICLE SPEED SENSOR
Step Check Yes No
1 CHECK POWER SUPPLY FOR COMBINA-
TION METER.
1) Remove the combination meter.
Assembly.>
2) Disconnect the combination meter harness
connector.
3) Turn the ignition switch to ON.
4) Measure the voltage between combination
meter connector and chassis ground.
Connector & terminal
(i10) No. 9 (+) — Chassis ground (
−):Is the voltage more than 10 V? Go to step 2.Check the harness
for open or short
between ignition
switch and combi-
nation meter.
2 CHECK POWER SUPPLY FOR COMBINA-
TION METER.
Measure the voltage between combination
meter connector and chassis ground.
Connector & terminal
(i10) No. 8 (+) — Chassis ground (
−):Is the voltage more than 10 V? Go to step 3.Check the harness
for open or short
between fuse and
combination
meter.
3 CHECK GROUND CIRCUIT OF COMBINA-
TION METER.
1) Turn the ignition switch to OFF.
2) Measure the resistance of harness
between combination meter connector and
chassis ground.
Connector & terminal
(i10) No. 10 — Chassis ground:Is the resistance less than 10
Ω?Replace the com-
bination meter
printed circuit.Repair the wiring
harness.
Step Check Yes No
1 CHECK VEHICLE SPEED SENSOR.
1) Lift-up the vehicle and support it with rigid
racks.
2) Remove the combination meter with har-
ness connector.
3) Drive the vehicle at a speed greater than 20
km/h (12 MPH).
Warning:
Be careful not to get caught in the running
wheels.
4) Measure the voltage between combination
meter connector and chassis ground.
Connector & terminal
(i10) No. 12 (+) — Chassis ground (
−):Is the voltage 1 V ← → 5 V? Check the speed-
ometer.
TION, Speedome-
ter.>Go to step 2.
2 CHECK VEHICLE SPEED SENSOR POWER
SUPPLY.
1) Turn the ignition switch to OFF.
2) Disconnect the vehicle speed sensor har-
ness connector.
3) Turn the ignition switch to ON.
4) Measure the voltage between vehicle
speed sensor connector and engine ground.
Connector & terminal
(B17) No. 3 (+) — Engine ground (
−):Is the voltage more than 10 V? Go to step 3.Check the harness
for open or short
between ignition
switch and vehicle
speed sensor.
Page 390 of 2870

IDI-6
INSTRUMENTATION/DRIVER INFO
Combination Meter System
4. CHECK TRANSMISSION CONTROL MODULE (TCM)
3 CHECK HARNESS BETWEEN VEHICLE
SPEED SENSOR AND ENGINE GROUND.
1) Turn the ignition switch to OFF.
2) Measure the resistance between vehicle
speed sensor connector and engine ground.
Connector & terminal
(B17) No. 2 — Engine ground:Is the resistance less than 10
Ω?Go to step 4.Repair the wiring
harness.
4 CHECK HARNESS BETWEEN VEHICLE
SPEED SENSOR AND COMBINATION
METER.
1) Disconnect the connector from combination
meter.
2) Measure the resistance between vehicle
speed sensor harness connector and combi-
nation meter harness connector.
Connector & terminal
(B17) No. 1 — (i10) No. 12:Is the resistance less than 10
Ω?Replace the vehi-
cle speed sensor.Repair the wiring
harness.
Step Check Yes No
1 CHECK TCM SIGNAL.
1) Lift-up the vehicle and support it with rigid
racks.
2) Drive the vehicle faster than 10 km/h (6
MPH).
Warning:
Be careful not to get caught in the running
wheels.
3) Measure the voltage between TCM con-
nector and chassis ground.
Connector & terminal
(B56) No. 17 (+) — Chassis ground (
−):Is the voltage 1 V ← → 5 V? Go to step 2.Check TCM.
Basic Diagnostic
Procedure.>
2 CHECK HARNESS BETWEEN TCM AND
COMBINATION METER.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from TCM and
combination meter.
3) Measure the resistance between TCM har-
ness connector and combination meter har-
ness connector.
Connector & terminal
(B56) No. 17 — (i10) No. 12:Is the resistance less than 10
Ω?Check the speedo
meter.
Speedometer.>Repair the wiring
harness. Step Check Yes No
Page 391 of 2870

IDI-7
INSTRUMENTATION/DRIVER INFO
Combination Meter System
5. CHECK ENGINE CONTROL MODULE (ECM)
6. CHECK FUEL LEVEL SENSOR
Step Check Yes No
1 CHECK ECM SIGNAL.
1) Start the engine.
2) Measure the voltage between ECM con-
nector and engine ground.
Connector & terminal
Non-turbo model
(B134) No. 10 (+) — Engine ground (
−):
Turbo model
(B134) No. 23 (+) — Engine ground (
−):Is the voltage 0 V ← → 14 V? Go to step 2.Check ECM.
Basic Diagnostics
Procedure.>
Basic Diagnostics
Procedure.>
2 CHECK HARNESS BETWEEN COMBINA-
TION METER AND ECM.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from ECM and
combination meter.
3) Measure the resistance between ECM har-
ness connector and combination meter har-
ness connector.
Connector & terminal
Non-turbo model
(B134) No. 10 — (i10) No. 11:
Turbo model
(B134) No. 23 — (i10) No. 11:Is the resistance less than 10
Ω?Check the tachom-
eter.
Tachometer.>Repair the wiring
harness.
Step Check Yes No
1 CHECK FUEL LEVEL SENSOR.
1) Remove the fuel level sensor.
sor.>
2) Measure the resistance between fuel level
sensor terminals when setting the float to
FULL and EMPTY position.
Te r m i n a l s
No. 3 — No. 5:Is the resistance 0.5 to 2.5 Ω
(FULL) and 50 to 52 Ω
(EMPTY)?Go to step 2.Replace the fuel
level sensor.
2 CHECK FUEL SUB LEVEL SENSOR.
1) Remove the fuel sub level sensor.
Sensor.>
2) Measure the resistance between fuel sub
level sensor terminals when setting the float to
FULL and EMPTY position.
Te r m i n a l s
No. 1 — No. 2:Is the resistance 0.5 to 2.5 Ω
(FULL) and 42 to 44 Ω
(EMPTY)?Go to step 3.Replace the fuel
sub level sensor.
3 CHECK HARNESS BETWEEN FUEL SUB
LEVEL SENSOR AND COMBINATION
METER.
1) Disconnect the connector from combination
meter.
2) Measure the resistance between fuel sub
level sensor harness connector terminal and
combination meter harness connector termi-
nal.
Connector & terminal
(R59) No. 1 — (i11) No. 1:Is the resistance less than 10
Ω?Go to step 4.Repair the wiring
harness.