2004 SUBARU FORESTER engine coolant

AC-39
HVAC SYSTEM (HEATER, VENTILATOR AND A/C)
Heater Cooling Unit
14.Heater Cooling Unit
A: REMOVAL
1) Disconnect the ground cable from battery.
2) Using the refrigerant recovery system, dis-
charge refrigerant. Refrigerant Recovery Procedure.>
3) Drain the engine coolant from radiator.
4) Remove the bolt securing expansion valve and
pipe in engine compartment. Release the heater
hose clamps in engine compartment to remove the
hoses.
5) Remove the instrument panel. REMOVAL, Instrument Panel Assembly.>
6) Remove the support beam.
7) Remove the blower motor unit assembly. to AC-32, REMOVAL, Blower Motor Unit Assem-
bly.>
8) Disconnect the servo motor connectors.
9) Remove the bolt and nuts to remove the heater
and cooling unit.
B: INSTALLATION
1) Install in the reverse order of removal.
2) Charge refrigerant. TION, Refrigerant Charging Procedure.>
Tightening torque:
Refer to COMPONENT in General Descrip-
tion. COMPONENT, General Description.>
AC-00870
AC-00055

AC-49
HVAC SYSTEM (HEATER, VENTILATOR AND A/C)
Heater Cock Solenoid Valve
24.Heater Cock Solenoid Valve
A: REMOVAL
1) Drain the engine coolant.
COOLANT, REPLACEMENT, Engine Coolant.>
2) Remove the battery.
3) Remove the two bolts and disconnect harness
connector, and move the washer tank forward.
4) Disconnect the harness connector (A) of the
heater cock solenoid valve.
5) Remove the two bolts to remove the heater cock
solenoid from the bracket.
6) Pull out the heater cock solenoid. Loosen the
hose clamp and disconnect the two heater hoses.
B: INSTALLATION
Install in the reverse order of removal.
C: INSPECTION
1) Remove the heater cock solenoid valve. AC-49, REMOVAL, Heater Cock Solenoid Valve.>
2) Connect the positive terminal of battery to No. 1
terminal of heater cock solenoid valve, and the
ground terminal to No. 2 terminal. Check that the
heater cock solenoid valve opens and closes nor-
mally.
If any failure is found, replace the heater cock sole-
noid valve.
WW-00011
AC-00886
(A)
AC-00887
1 2
AC-00888

AC-50
HVAC SYSTEM (HEATER, VENTILATOR AND A/C)
General Diagnostics
25.General Diagnostics
A: INSPECTION
Symptom Repair order
Blower motorDoes not run.Fuse
Blower motor relay
Wiring harness
Blower motor
Blower motor resistor (Manual A/C model)
Blower switch
Noise Blower motor
CompressorDoes not run.Refrigerant
Fuse
A/C relay
Wiring harness
Magnet clutch
Compressor
Pressure switch
A/C switch
Blower switch
NoiseV- B e l t
Magnet clutch
Compressor
Condenser fanDoes not run.Fuse
Sub fan relay
Wiring harness
Noise Condenser fan motor
Cold air not emitted.Refrigerant
V- B e l t
Magnet clutch
Compressor
Pressure switch
Blower fan relay, Blower motor
A/C switch
Blower switch
Wiring harness
Heater duct
Heater vent duct
Control unit
Expansion valve
Evaporator
Air mix actuator (Auto A/C), Temperature control cable (Manual
A/C)
Warm air not emitted.Engine coolant
Aspirator hose
Blower switch
Air mix actuator (Auto A/C), Temperature control cable (Manual
A/C)
Heater core
Heater cock solenoid valve (Non-turbo model for EC/EK)

AC-7
HVAC SYSTEM (AUTO A/C)(DIAGNOSTIC)
Auto A/C Control Module I/O Signal
4. Auto A/C Control Module I/O Signal
A: ELECTRICAL SPECIFICATION
Terminal No. Content Measuring conditionSpecified
value
B9
Mode door actuator power supplyChanges outlet from VENT to DEF.
*2
B8 Changes outlet from DEF to VENT.
B7
Air mix door actuator power supplyChanges air mix door from COOL to HOT.
*1
B6 Changes air mix door from HOT to COOL.
B5 IGN power supply Ignition switch: ON Battery voltage
B4 Battery power supply Ignition switch: OFF, ACC, ON Battery voltage
B3 Sunload sensorIgnition switch: ON and under normal sunload
(without sunload: 5 V)3 V
B2 Evaporator sensor Ignition switch: ON 5 V or less
B1 Air mix door actuator P.B.R. signalAir mix door: COOL position 0.5 V
Air mix door: HOT position 4.5 V
B20
Intake door actuator signalAir inlet: FRESH (other positions: 12 V) 0 V
B19 Air inlet: MIX (other positions: 12 V) 0 V
B18 Air inlet: RECIRC (other positions: 12 V) 0 V
B17 A/C ON signal A/C: ON (A/C OFF: 0 V) 8 — 10 V
B16 Blower motor control *3 *3
B15 Blower fan ON signalWhen blower fan running (when blower fan not
running: 12 V)0 V
B13 Engine coolant temperature sensor When the engine coolant is at 49°C (120°F) 8.9 V
B12 In-vehicle sensor — —
B11 Ground When there is continuity to chassis ground 0 Ω
A7 Air mix door actuator P.B.R. reference voltage Ignition switch: ON 5 V
A5 Mode door actuator position detection signal OutletBI-LEVEL, DEF 5 V
VENT, HEAT, DEF/HEAT 0 V
A4 Mode door actuator position detection signal OutletHEAT, DEF/HEAT, DEF 5 V
VENT, BI-LEVEL 0 V
A1 Illumination power supplyIgnition switch: ON, light switch: ON Battery voltage
Ignition switch: ON, light switch: OFF 0 V
A16 Sensor ground When there is continuity to chassis ground 0 Ω
AC-00099
1 2 3 4 5 6 7 8 910
11 12 13 14 15 16 17 18 19 201 2 3 4 5 6 7 8
9
10 11 12 13 14 15 16
i48B: To A:To
i49

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

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

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 POWER SUPPLY AND
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: 5, CHECK VEHICLE
SPEED SENSOR,
INSPECTION, Combi-
nation Meter System.>
AT model: 6, CHECK TRANSMIS-
SION CONTROL MOD-
ULE (TCM),
INSPECTION, Combi-
nation Meter System.>
Tachometer does not operate. (1) ECM
(2) Harness
(3) Tachometer ENGINE CONTROL
MODULE (ECM),
INSPECTION, Combi-
nation Meter System.>
Fuel gauge does not operate. (1) Fuel level sensor
(2) Harness
(3) Fuel gauge FUEL LEVEL SEN-
SOR, INSPECTION,
Combination Meter
System.>
Water temperature gauge does not operate. (1) Engine coolant temperature sensor
(2) Harness
(3) Water temperature gauge ENGINE COOLANT
TEMPERATURE SEN-
SOR, INSPECTION,
Combination Meter
System.>
Outside temperature indicator does not operate. (1) Ambient sensor
(2) Harness
(3) Combination meter OUTSIDE TEMPERA-
TURE INDICATOR,
INSPECTION, Combi-
nation Meter System.>

IDI-8
INSTRUMENTATION/DRIVER INFO
Combination Meter System
7. CHECK ENGINE COOLANT TEMPERATURE SENSOR
8. CHECK OUTSIDE TEMPERATURE INDICATOR
4 CHECK HARNESS BETWEEN FUEL LEVEL
SENSOR AND FUEL SUB LEVEL SENSOR.
Measure the resistance between fuel level sen-
sor harness connector terminal and fuel sub
level sensor harness connector terminal.
Connector & terminal
(R58) No. 3 — (R59) No. 2:Is the resistance less than 10
Ω?Go to step 5.Repair the wiring
harness.
5 CHECK FUEL LEVEL SENSOR GROUND
CIRCUIT.
Measure the resistance between fuel level sen-
sor harness connector terminal and chassis
ground.
Connector & terminal
(R58) No. 5 — Chassis ground:Is the resistance less than 10
Ω?Check the fuel
gauge. IDI-15, INSPEC-
TION, Fuel
Gauge.>Repair the wiring
harness.
Step Check Yes No
1 CHECK ENGINE COOLANT TEMPERATURE
SENSOR.
Check the engine coolant temperature sensor.
cedure.>Is the engine coolant tempera-
ture sensor OK?Go to step 2.Replace the
engine coolant
temperature sen-
sor.
2 CHECK HARNESS BETWEEN ENGINE
COOLANT TEMPERATURE SENSOR AND
COMBINATION METER.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from engine cool-
ant temperature sensor and combination
meter.
3) Measure the resistance between engine
coolant temperature sensor harness connector
and combination meter harness connector.
Connector & terminal
(E8) No. 3 — (i11) No. 10:Is the resistance less than 10
Ω?Go to step 3.Repair the wiring
harness.
3 CHECK WATER TEMPERATURE GAUGE
GROUND CIRCUIT.
Measure the resistance between combination
meter harness connector terminal and chassis
ground.
Connector & terminal
(i11) No. 9 — Chassis ground:Is the resistance less than 10
Ω?Check the water
temperature
gauge. IDI-16, INSPEC-
TION, Water Tem-
perature Gauge.>Repair the wiring
harness.
Step Check Yes No
1 CHECK POWER SUPPLY FOR AMBIENT
SENSOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from outside
temperature sensor.
3) Turn the ignition switch to ON.
4) Measure the voltage between outside tem-
perature sensor harness connector terminal
and chassis ground.
Connector & terminal
(F78) No. 2 (+) — Chassis ground (
−):Is the voltage more than 4 V? Go to step 3.Go to step 2. Step Check Yes No