2004 SUBARU FORESTER relay

CO(H4SO)-16
COOLING
Radiator Fan System
14 CHECK FAN MODE RELAY.
Measure the resistance of fan mode relay.
Te r m i n a l
No. 6 — No. 9:Is the resistance less than 1
Ω?Go to step 15.Replace the fan
mode relay.
15 CHECK RESISTANCE BETWEEN FAN
MODE RELAY TERMINAL AND SUB FAN
MOTOR CONNECTOR.
1) Disconnect the connector from sub fan
motor.
2) Measure the resistance between fan mode
relay terminal and sub fan motor connector.
Connector & terminal
Turbo AT model
(F16) No. 1 — (F27) No. 6:
Except turbo AT model
(F16) No. 2 — (F27) No. 6:Is the resistance less than 1
Ω?Go to step 16.Repair the open
harness between
fan mode relay ter-
minal and sub fan
motor connector.
16 CHECK SUB FAN MOTOR AND GROUND
CIRCUIT.
Measure the resistance between sub fan motor
connector and chassis ground.
Connector & terminal
Turbo AT model
(F16) No. 2 — Chassis ground:
Except turbo AT model
(F16) No. 1 — Chassis ground:Is the resistance less than 5
Ω?Go to step 17.Repair the open
harness between
sub fan motor con-
nector and chassis
ground.
17 CHECK POOR CONTACT.
Check poor contact in sub fan motor connec-
tor.Is there poor contact in sub fan
motor connector?Repair poor con-
tact in sub fan
motor connector.Go to step 18.
18 CHECK SUB FAN MOTOR.
Connect the battery positive (+) terminal to ter-
minal No. 2 (except turbo AT model), No. 1
(turbo AT model), and ground (−) terminal to
terminal No. 1 (except turbo AT model), No. 2
(turbo AT model) of sub fan motor.Does the sub fan rotate? Go to step 19.Replace the sub
fan motor with new
one.
19 CHECK HARNESS BETWEEN MAIN FAN
RELAY AND ECM.
1) Disconnect the connector from ECM.
2) Measure the resistance between fan relay 1
terminal and ECM connector.
Connector & terminal
Turbo model
(B135) No. 25 — (F27) No. 32:
Non-turbo model
(B134) No. 14 — (F27) No. 32:Is the resistance less than 1
Ω?Go to step 20.Repair the open
harness between
fan relay 1 terminal
and ECM.
20 CHECK POOR CONTACT.
Check poor contact in ECM connector.Is there poor contact in ECM
connector?Repair poor con-
tact in ECM con-
nector.Contact with SUB-
ARU dealers.
21 CHECK POWER SUPPLY TO SUB FAN RE-
LAY.
1) Turn the ignition switch to OFF.
2) Remove the sub fan relay from A/C relay
holder.
3) Measure the voltage between sub fan relay
terminal and chassis ground.
Connector & terminal
(F27) No. 28 (+) — Chassis ground (
−):Is the voltage more than 10 V? Go to step 22.Go to step 23. Step Check Yes No

CO(H4SO)-17
COOLING
Radiator Fan System
22 CHECK POWER SUPPLY TO SUB FAN RE-
LAY.
1) Turn the ignition switch to ON.
2) Measure the voltage between sub fan relay
terminal and chassis ground.
Connector & terminal
(F27) No. 25 (+) — Chassis ground (
−):Is the voltage more than 10 V? Go to step 26.Go to step 25.
23 CHECK FUSE.
1) Remove the fuse from A/C relay holder.
2) Check the condition of fuse.Is the fuse blown out? Replace the fuse. Go to step 24.
24 CHECK HARNESS BETWEEN FUSE TERMI-
NAL AND SUB FAN RELAY TERMINAL.
1) Turn the ignition switch to OFF.
2) Measure the resistance between fuse ter-
minal and sub fan relay terminal.
Te r m i n a l
No. 4 — No. 28:Is the resistance less than 1
Ω?Repair the power
supply line.Repair the open
harness.
25 CHECK FUSE.
1) Turn the ignition switch to OFF.
2) Remove the fuse No. 17.
3) Check the condition of fuse.Is the fuse blown out? Replace the fuse. Repair the power
supply line.
26 CHECK SUB FAN RELAY.
1) Turn the ignition switch to OFF.
2) Remove the sub fan relay from A/C relay
holder.
3) Measure the resistance of sub fan relay.
Te r m i n a l
No. 28 — No. 29:Is the resistance more than 1
MΩ?Go to step 27.Replace the sub
fan relay.
27 CHECK SUB FAN RELAY.
1) Connect the battery to terminals No. 25 and
No. 27 of sub fan relay.
2) Measure the resistance of sub fan relay.
Te r m i n a l
No. 28 — No. 29:Is the resistance less than 1
Ω?Go to step 28.Replace the sub
fan relay.
28 CHECK HARNESS BETWEEN SUB FAN RE-
LAY TERMINAL AND SUB FAN MOTOR
CONNECTOR.
1) Disconnect the connector from sub fan
motor.
2) Measure the resistance between sub fan
relay terminal and sub fan motor connector.
Connector & terminal
Turbo AT model
(F16) No. 1 — (F27) No. 29:
Except turbo AT model
(F16) No. 2 — (F27) No. 29:Is the resistance less than 1
Ω?Go to step 30.Repair the open
harness between
sub fan relay ter-
minal and sub fan
motor connector.
29 CHECK HARNESS BETWEEN SUB FAN RE-
LAY AND ECM.
1) Disconnect the connector from ECM.
2) Measure the resistance between sub fan
relay terminal and ECM connector.
Connector & terminal
Non-turbo model: (B134) No. 13 — (F27)
No. 27:
Turbo model: (B135) No. 24 — (F27) No.
27:Is the resistance less than 1
Ω?Go to step 30.Repair the open
harness between
sub fan relay ter-
minal and ECM. Step Check Yes No

CO(H4SO)-18
COOLING
Radiator Fan System
30 CHECK HARNESS BETWEEN FAN MODE
RELAY AND ECM.
Measure the resistance between fan mode
relay terminal and ECM connector.
Connector & terminal
Non-turbo model
(B134) No. 13 — (F27) No. 7:
Turbo model
(B135) No. 24 — (F27) No. 7:Is the resistance less than 1
Ω?Go to step 31.Repair the open
harness between
fan mode relay ter-
minal and ECM.
31 CHECK POOR CONTACT.
Check poor contact in ECM connector.Is there poor contact in ECM
connector?Repair the poor
contact in ECM
connector.Contact with SUB-
ARU dealers.
N
OTE:
Probable cause is
deterioration of
multiple parts.
32 CHECK OPERATION OF RADIATOR FAN.Does the radiator main fan
rotate when the radiator main
and sub fan do not rotate at
high speed?Go to step 21.Go to step 33.
33 CHECK GROUND CIRCUIT OF FAN MODE
RELAY.
1) Remove the fan mode relay from A/C relay
holder.
2) Measure the resistance between fan mode
relay terminal and chassis ground.
Connector & terminal
(F27) No. 8 — Chassis ground:Is the resistance less than 1
Ω?Go to step 34.Repair the open
harness between
fan mode relay
and chassis
ground.
34 CHECK POWER SUPPLY TO FAN MODE
RELAY.
1) Turn the ignition switch to ON.
2) Measure the voltage between fan mode
relay terminal and chassis ground.
Connector & terminal
(F27) No. 5 (+) — Chassis ground (
−):Is the voltage more than 10 V? Go to step 35.Repair the power
supply line.
35 CHECK FAN MODE RELAY.
1) Turn the ignition switch to OFF.
2) Remove the fan mode relay.
3) Measure the resistance of fan mode relay.
Te r m i n a l
(F27) No. 8 — (F27) No. 9:Is the resistance more than 1
MΩ?Go to step 36.Replace the fan
mode relay.
36 CHECK FAN MODE RELAY.
1) Connect the battery to terminals No. 5 and
No. 7 of fan mode relay.
2) Measure the resistance of fan mode relay.
Te r m i n a l
(F27) No. 8 — (F27) No. 9:Is the resistance less than 1
Ω?Go to step 29.Replace the fan
mode relay. Step Check Yes No

CO(H4SO)-43
COOLING
Engine Cooling System Trouble in General
12.Engine Cooling System Trouble in General
A: INSPECTION
Trouble Possible cause Corrective action
Over-heatinga. Insufficient engine coolantReplenish the engine coolant, inspect for leakage, and
repair.
b. Loose timing belt Repair or replace the timing belt tensioner.
c. Oil on drive belt Replace.
d. Malfunction of thermostat Replace.
e. Malfunction of water pump Replace.
f. Clogged engine coolant passage Clean.
g. Improper ignition timingInspect and repair the ignition control system.

nostics Procedure.>
h. Clogged or leaking radiator Clean or repair, or replace.
i. Improper engine oil in engine coolant Replace the engine coolant.
j. Air/fuel mixture ratio too leanInspect and repair the fuel injection system.

nostics Procedure.>
k. Excessive back pressure in exhaust system Clean or replace.
l. Insufficient clearance between piston and cylinder Adjust or replace.
m. Slipping clutch Repair or replace.
n. Dragging brake Adjust.
o. Defective thermostat Replace.
p. Malfunction of radiator fanInspect the radiator fan relay, engine coolant tempera-
ture sensor or radiator motor and replace there.
Over-coolinga. Atmospheric temperature extremely low Partly cover the radiator front area.
b. Defective thermostat Replace.
Engine coolant
leaks.a. Loosened or damaged connecting units on hoses Repair or replace.
b. Leakage from water pump Replace.
c. Leakage from water pipe Repair or replace.
d. Leakage around cylinder head gasket Retighten the cylinder head bolts or replace gasket.
e. Damaged or cracked cylinder head and crankcase Repair or replace.
f. Damaged or cracked thermostat case Repair or replace.
g. Leakage from radiator Repair or replace.
Noisea. Defective drive belt Replace.
b. Defective radiator fan Replace.
c. Defective water pump bearing Replace the water pump.
d. Defective water pump mechanical seal Replace the water pump.

EN(H4SO)-6
ENGINE (DIAGNOSTIC)
General Description
3. General Description
A: CAUTION
1) Airbag system wiring harness is routed near the
ECM, main relay and fuel pump relay.
CAUTION:
 All air bag system wiring harnesses and con-
nectors are yellow. Do not use the electrical
test equipment on these circuits.
 Be careful not to damage the Airbag system
wiring harness when servicing the ECM, TCM,
main relay and fuel pump relay.
2) Never connect the battery in reverse polarity.
 The ECM will be destroyed immediately.
 The fuel injector and other part will be damaged.
3) Do not disconnect the battery terminals while the
engine is running.
A large counter electromotive force will be generat-
ed in the generator, and this voltage may damage
electronic parts such as ECM, etc.
4) Before disconnecting the connectors of each
sensor and the ECM, be sure to turn the ignition
switch to OFF.
5) Poor contact has been identified as a primary
cause of this problem. Measure the voltage or re-
sistance of individual sensor or all electrical control
modules using a tapered pin with a diameter of less
than 0.64 mm (0.025 in). Do not insert the pin more
than 5 mm (0.20 in) into the part.
6) Remove the ECM from the located position after
disconnecting two cables on battery.
Otherwise, the ECM may be damaged.
CAUTION:
When replacing the ECM, be careful not to use
the wrong spec. ECM to avoid any damage on
the fuel injection system.
7) Connectors to each sensor in the engine com-
partment and the harness connectors on the en-
gine side and body side are all designed to be
waterproof. However, it is still necessary to take
care not to allow water to get into the connectors
when washing the vehicle, or when servicing the
vehicle on a rainy day.8) Use ECM mounting stud bolts as the grounding
point to body when measuring voltage and resis-
tance inside the passenger compartment.
9) Use engine ground terminal or engine proper as
the grounding point to body when measuring volt-
age and resistance in the engine compartment.
10) Use TCM mounting stud bolts as the grounding
point to body when measuring voltage and resis-
tance inside the passenger compartment.
11) Every MFI-related part is a precision part. Do
not drop them.
12) Observe the following cautions when installing
a radio in MFI equipped models.
CAUTION:
 The antenna must be kept as far apart as pos-
sible from the control unit. (The ECM is located
under the steering column, inside of the instru-
ment panel lower trim panel.)
(A) Stud bolt
(A) Stud bolt
EN-00001
(A)
EN-00153
EN-00154(A)

EN(H4SO)-16
ENGINE (DIAGNOSTIC)
Electrical Component Location
 LHD MODEL
 RHD MODEL
(1) Inhibitor switch (4) Fuel pump relay (7) Starter
(2) Fuel pump (5) Radiator main fan relay
(3) Main relay (6) Radiator sub fan relay
EN-00251
(3)
(4)
EN-02400
EN-00252 (1)
(3) (7) (6)(5)(4)
(2)
EN-00253
(7) (6)(5)
(2)(3)(4)(1)

EN(H4SO)-22
ENGINE (DIAGNOSTIC)
Engine Control Module (ECM) I/O Signal
A/C switch B136 11ON: 10 — 13
OFF: 0ON: 12 — 14
OFF: 0—
Ignition switch B136 10 10 — 13 12 — 14 —
Neutral
Po si ti o n
SwitchMT B136 21ON: 12±0.5
OFF: 0Switch is ON when gear is in
neutral position.
AT B136 21ON: 0
OFF: 12±0.5Switch is ON when shifted into
“P” or “N” range.
Test Mode Connector B136 3 5 5 When connected: 0
Knock
sensorSignal B135 16 2.8 2.8 —
Shield B135 27 0 0 —
Back-up power supply B135 9 10 — 13 12 — 14 Ignition switch “OFF”: 10 — 13
Control module power
supplyB135 1 10 — 13 12 — 14 —
B135 2 10 — 13 12 — 14 —
Sensor power supply B135 3 5 5 —
Ignition
control#1, #2 B134 33 0 1 — 3.4 Waveform
#3, #4 B134 32 0 1 — 3.4 Waveform
Fuel injec-
tor#1 B134 34 10 — 13 1 — 14 Waveform
#2 B134 23 10 — 13 1 — 14 Waveform
#3 B134 22 10 — 13 1 — 14 Waveform
#4 B134 8 10 — 13 1 — 14 Waveform
Idle air
control
solenoid
valveSignal 1 B134 20 — 1 — 13 Waveform
Signal 2 B134 6 — 1 — 13 Waveform
Signal 3 B134 5 — 1 — 13 Waveform
Signal 4 B134 19 — 1 — 13 Waveform
Pow er
supplyB135 2 10 — 13 12 — 14 —
Fuel pump relay control B134 2ON: 0.5, or less
OFF: 10 — 130.5, or less —
A/C relay control B134 9ON: 0.5, or less
OFF: 10 — 13ON: 0.5, or less
OFF: 12 — 14—
Heater cock solenoid B134 11 10 — 13 12 — 14 —
Radiator fan relay 1 con-
trolB134 14ON: 0.5, or less
OFF: 10 — 13ON: 0.5, or less
OFF: 12 — 14—
Radiator fan relay 2 con-
trolB134 13ON: 0.5, or less
OFF: 10 — 13ON: 0.5, or less
OFF: 12 — 14Model with A/C
Self-shutoff control B136 12 10 — 13 12 — 14 —
Malfunction indicator
lightB134 28 — —Light “ON”: 1, or less
Light “OFF”: 10 — 14
Engine speed output B134 10 — 0 — 13, or more Waveform
Torque control 1 signal B136 1 5 5 —
Torque control 2 signal B136 18 5 5 —
Torque control cut signal B136 15 8 8 —
Purge control solenoid
valveB134 29ON: 1, or less
OFF: 10 — 13ON: 1, or less
OFF: 12 — 14—
Fuel level sensor B135 25 0.12 — 4.75 0.12 — 4.75 —
EGR valveSignal 1 B134 18 0 or 10 — 13 0 or 10 — 13 —
Signal 2 B134 17 0 or 10 — 13 0 or 10 — 13 —
Signal 3 B134 16 0 or 10 — 13 0 or 10 — 13 —
Signal 4 B134 15 0 or 10 — 13 0 or 10 — 13 —
AT diagnosis input sig-
nalB137 19Less than 1←→
More than 4Less than 1←→
More than 4Wavefor m DESCRIPTION Connector No. Terminal No.Signal (V)
NOTE
Ignition SW ON
(engine OFF)Engine ON
(Idling)

EN(H4SO)-30
ENGINE (DIAGNOSTIC)
Subaru Select Monitor
4. READ CURRENT DATA FOR ENGINE. (NORMAL MODE)
1) On the «Main Menu» display screen, select the {Each System Check} and press the [YES] key.
2) On the «System Selection Menu» display screen, select the {Engine} and press the [YES] key.
3) Press the [YES] key after the information of engine type was displayed.
4) On the «Engine Diagnosis» display screen, select the {Current Data Display/Save}, and then press the
[YES] key.
5) On the «Data Display Menu» display screen, select the {Data Display} and press the [YES] key.
6) Using the scroll key, scroll the display screen up or down until the desired data is shown.
 A list of the support data is shown in the following table.
Description Display Unit of measure
Battery voltage Battery Voltage V
Vehicle speed signal Meter vehicle speed km/h or MPH
Engine speed signal Engine speed rpm
Engine coolant temperature signal Engine coolant temperature°C or (°F)
Ignition timing signal Ignition timing deg
Throttle position signal Amount of intake air %
Throttle position signal Throttle Sensor Voltage V
Injection pulse width Fuel injection pulse width ms
Idle air control signal ISC Steps STEP
Engine load data Engine load %
Front oxygen (A/F) sensor resistance A/F sensor resistance value 1 ohm
Front oxygen (A/F) sensor output signal A/F sensor current value 1 —
Rear oxygen sensor output signalRear oxygen sensor voltage
valueV
Short term fuel trim A/F Compensation 1 %
Knock sensor signal Knock Correction deg
Atmospheric absolute pressure signal Atmospheric pressure mmHg, kPa, inHg or psi
Intake manifold relative pressure signal Mani. Relative Pressure mmHg, kPa, inHg or psi
Intake manifold absolute pressure signalIntake manifold absolute pres-
suremmHg, kPa, inHg or psi
A/F correction (short term fuel trim) by rear oxygen sensor A/F Compensation 3 %
Long term whole fuel trim A/F learning 1 %
Front oxygen (A/F) sensor heater current Front O2 heater current value A
Rear oxygen sensor heater current Rear O2 heater current value A
Canister purge control solenoid valve duty ratio CPC Valve Duty Ratio %
Fuel level signal Fuel level voltage V
Intake air temperature signal Intake air temperature°C or (°F)
Learned ignition timing Ignition learning value deg
EGR signal EGR Steps STEP
Ignition switch signal Ignition SW ON or OFF
Test mode connector signal Test mode signal ON or OFF
Neutral position switch signal Neutral SW ON or OFF
Air conditioning switch signal A/C SW ON or OFF
Air conditioning compressor signal A/C Compressor Signal ON or OFF
Radiator main fan relay signal Radiator fan relay 1 ON or OFF
Fuel pump relay signal Fuel pump relay ON or OFF
Knocking signal Knock signal ON or OFF
Radiator sub fan relay signal Radiator fan relay 2 ON or OFF
Power steering switch signal Power steering SW input signal ON or OFF
Engine torque control signal #1 AT coordinate request signal 1 ON or OFF
Engine torque control signal #2 AT coordinate request signal 2 ON or OFF