engine SUBARU FORESTER 2004 Service Repair Manual

EN(H4SO)-61
ENGINE (DIAGNOSTIC)
Diagnostics for Engine Starting Failure
C: CHECK POWER SUPPLY AND GROUND LINE OF ENGINE CONTROL MOD-
ULE (ECM)
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode ERATION, Clear Memory Mode.> and Inspection Mode tion Mode.>.
WIRING DIAGRAM:
EN-02381
B72
3412
BATTERYIGNITION
SWITCH MAIN RELAY
SBF-4SBF-1
SBF-5
B72B61F44
B2 B1 C12 C16
B21C5
A35
A7
C26
D14B9
C10 C23
No.11B47
E2 B21 1 2 3 5 6 4
ECM
EE
1
7
4
B134
B135
B136 A :
C :
D :B137 B :
C19
8
15
16 14 13
E
3412
56
123
4
56
78
9
1011 12
1314 15 16
B137B135B21B47
MT
MT
F44
B134
12345678
1234567891011121314151617181920212223242526272829303132333435
567
82 1
94
310
24 22 23 251112131415
26 27
281617181920 21
4
1
53
2618 15 167891011
17 19
20121314
B136
5
2
84
3923 20 211011
221617
24
2512136
261915
14
1
7
18
A : C :D :B :
LHDLHD
RHDRHD

EN(H4SO)-62
ENGINE (DIAGNOSTIC)
Diagnostics for Engine Starting Failure
Step Check Yes No
1 CHECK MAIN RELAY.
1) Turn the ignition switch to OFF.
2) Remove the main relay.
3) Connect the battery to main relay terminals
No. 1 and No. 2.
4) Measure the resistance between main relay
terminals.
Te r m i n a l s
No. 3 — No. 5:
No. 4 — No. 6:Is the resistance less than 10
Ω?Go to step 2.Replace the main
relay.
2 CHECK GROUND CIRCUIT FOR ECM.
1) Disconnect the connector from ECM.
2) Measure the resistance of harness
between ECM and chassis ground.
Connector & terminal
(B134) No. 7 — Chassis ground:
(B134) No. 35 — Chassis ground:
(B135) No. 21 — Chassis ground:
(B136) No. 5 — Chassis ground:
(B136) No. 16 — Chassis ground:
(B136) No. 19 — Chassis ground: (MT
model)
(B136) No. 26 — Chassis ground:
(B137) No. 14 — Chassis ground:Is the resistance less than 5
Ω?Go to step 3.Repair open circuit
in harness
between ECM
connector and
engine ground ter-
minal.
3 CHECK INPUT VOLTAGE OF ECM.
Measure the voltage between ECM connector
and chassis ground.
Connector & terminal
(B135) No. 9 (+) — Chassis ground (
−):Is the voltage more than 10 V? Go to step 4.Repair open or
ground short cir-
cuit of power sup-
ply circuit.
4 CHECK INPUT VOLTAGE OF ECM.
1) Turn the ignition switch to ON.
2) Measure the voltage between ECM con-
nector and chassis ground.
Connector & terminal
(B136) No. 10 (+) — Chassis ground (
−):Is the voltage more than 10 V? Go to step 5.Repair open or
ground short cir-
cuit of power sup-
ply circuit.
5 CHECK HARNESS BETWEEN ECM AND
MAIN RELAY CONNECTOR.
1) Turn the ignition switch to OFF.
2) Measure the resistance between ECM and
chassis ground.
Connector & terminal
(B136) No. 12 — Chassis ground:Is the resistance more than 1
MΩ?Go to step 6.Repair ground
short circuit in har-
ness between
ECM connector
and main relay
connector, then
replace the ECM.
6 CHECK OUTPUT VOLTAGE FROM ECM.
1) Connect the connector to ECM.
2) Turn the ignition switch to ON.
3) Measure the voltage between ECM con-
nector and chassis ground.
Connector & terminal
(B136) No. 12 (+) — Chassis ground (
−):Is the voltage more than 10 V? Go to step 7.Replace the ECM.
FU(H4SO)-44,
Engine Control
Module (ECM).>
7 CHECK INPUT VOLTAGE OF MAIN RELAY.
Measure the voltage between main relay con-
nector and chassis ground.
Connector & terminal
(B47) No. 2 (+) — Chassis ground (
−):Is the voltage more than 10 V? Go to step 8.Repair open circuit
in harness
between ECM
connector and
main relay connec-
tor.

EN(H4SO)-63
ENGINE (DIAGNOSTIC)
Diagnostics for Engine Starting Failure
8 CHECK GROUND CIRCUIT OF MAIN RE-
LAY.
1) Turn the ignition switch to OFF.
2) Measure the resistance between main relay
connector and chassis ground.
Connector & terminal
(B47) No. 1 — Chassis ground:Is the resistance less than 5
Ω?Go to step 9.Repair open circuit
between main
relay and chassis
ground.
9 CHECK INPUT VOLTAGE OF MAIN RELAY.
Measure the voltage between main relay con-
nector and chassis ground.
Connector & terminal
(B47) No. 5 (+) — Chassis ground (
−):
(B47) No. 6 (+) — Chassis ground (
−):Is the voltage more than 10 V? Go to step 10.Repair open or
ground short cir-
cuit in harness of
power supply cir-
cuit.
10 CHECK INPUT VOLTAGE OF ECM.
1) Connect the main relay connector.
2) Turn the ignition switch to ON.
3) Measure the voltage between ECM con-
nector and chassis ground.
Connector & terminal
(B135) No. 1 (+) — Chassis ground (
−):
(B135) No. 2 (+) — Chassis ground (
−):
(B136) No. 23 (+) — Chassis ground (
−):Is the voltage more than 10 V? Check ignition
control system.
EN(H4SO)-64,
IGNITION CON-
TROL SYSTEM,
Diagnostics for
Engine Starting
Fa il u r e. >Repair open or
ground short cir-
cuit in harness
between ECM
connector and
main relay connec-
tor. Step Check Yes No

EN(H4SO)-64
ENGINE (DIAGNOSTIC)
Diagnostics for Engine Starting Failure
D: IGNITION CONTROL SYSTEM
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode ERATION, Clear Memory Mode.> and Inspection Mode tion Mode.>.
WIRING DIAGRAM:
EN-00263
BATTERY
1 IGNITION
SWITCHSBF-44
A32
B21
E2
B134
1234567891011121314151617181920212223242526272829303132333435
B72
34
12
SBF-1No.11
54146
1234
B136 C:
B134 A:ECM
A33C26
34
12
IGNITOR
&
IGNITOR COIL ASSY
1234
E12B21
123
4
56
78
9
1011 12
1314 15 16
B72
B136
5
2
84
3923 20 211011
221617
24
2512136
261915
14
1
7
18
E12
C:
A:

EN(H4SO)-65
ENGINE (DIAGNOSTIC)
Diagnostics for Engine Starting Failure
Step Check Yes No
1 CHECK IGNITION SYSTEM FOR SPARKS.
1) Remove the plug cord cap from each spark
plug.
2) Install the new spark plug on plug cord cap.
CAUTION:
Do not remove the spark plug from engine.
3) Contact the spark plug’s thread portion on
engine.
4) While opening the throttle valve fully, crank
the engine to check that spark occurs at each
cylinder.Does spark occur at each cyl-
inder?Check fuel pump
system. EN(H4SO)-67,
FUEL PUMP CIR-
CUIT, Diagnostics
for Engine Start-
ing Failure.>Go to step 2.
2 CHECK POWER SUPPLY CIRCUIT FOR IG-
NITION COIL & IGNITOR ASSY.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from ignition coil
& ignitor ASSY.
3) Turn the ignition switch to ON.
4) Measure the power supply voltage between
ignition coil & ignitor ASSY connector and
engine ground.
Connector & terminal
(E12) No. 2 (+) — Engine ground (
−):Is the voltage more than 10 V? Go to step 3.Repair harness
and connector.
N
OTE:
In this case repair
the following:
 Open circuit in
harness between
ignition coil & igni-
tor ASSY, and
main relay connec-
tor
 Poor contact in
coupling connector
 Blown out fuse
3 CHECK HARNESS OF IGNITION COIL & IG-
NITOR ASSY GROUND CIRCUIT.
1) Turn the ignition switch to OFF.
2) Measure the resistance between ignition
coil & ignitor ASSY connector and engine
ground.
Connector & terminal
(E12) No. 3 — Engine ground:Is the resistance less than 5
Ω?Go to step 4.Repair harness
and connector.
N
OTE:
In this case repair
the following:
 Open circuit in
harness between
ignition coil & igni-
tor ASSY connec-
tor and engine
ground terminal
4 CHECK IGNITION COIL & IGNITOR ASSY.
1) Remove the spark plug cords.
2) Measure the resistance between spark
plug cord contact portions to check secondary
coil.
Te r m i n a l s
No. 1 — No. 2:
No. 3 — No. 4:Is the resistance 10 — 15 kΩ? Go to step 5.Replace the igni-
tion coil & ignitor
ASSY. IG(H4SO)-8, Igni-
tion Coil & Ignitor
Assembly.>
5 CHECK INPUT SIGNAL FOR IGNITION COIL
& IGNITOR ASSY.
1) Connect the connector to ignition coil &
ignitor ASSY.
2) Check if voltage varies synchronously with
engine speed when cranking, while monitoring
voltage between ignition coil & ignitor ASSY
connector and engine ground.
Connector & terminal
(E12) No. 1 (+) — Engine ground (
−):
(E12) No. 4 (+) — Engine ground (
−):Does the voltage vary more
than 10 V?Go to step 6.Replace the igni-
tion coil & ignitor
ASSY. IG(H4SO)-8, Igni-
tion Coil & Ignitor
Assembly.>

EN(H4SO)-66
ENGINE (DIAGNOSTIC)
Diagnostics for Engine Starting Failure
6 CHECK HARNESS BETWEEN ECM AND IG-
NITION COIL & IGNITOR ASSY CONNEC-
TOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from ECM.
3) Disconnect the connector from ignition coil
& ignitor ASSY.
4) Measure the resistance of harness
between ECM and ignition coil & ignitor ASSY
connector.
Connector & terminal
(B134) No. 32 — (E12) No. 1:
(B134) No. 32 — (E12) No. 4:Is the resistance less than 1
Ω?Go to step 7.Repair harness
and connector.
N
OTE:
In this case repair
the following:
 Open circuit in
harness between
ECM and ignition
coil & ignitor ASSY
connector.
 Poor contact in
coupling connector
7 CHECK HARNESS BETWEEN ECM AND IG-
NITION COIL & IGNITOR ASSY CONNEC-
TOR.
Measure the resistance of harness between
ECM and engine ground.
Connector & terminal:
(B134) No. 32 — Engine ground:Is the resistance more than 1
MΩ?Go to step 8.Repair ground
short circuit in har-
ness between
ECM and ignition
coil & ignitor ASSY
connector.
8 CHECK POOR CONTACT.
Check poor contact in ECM connector. Is there poor contact in ECM
connector?Repair the poor
contact in ECM
connector.Check fuel pump
circuit. EN(H4SO)-67,
FUEL PUMP CIR-
CUIT, Diagnostics
for Engine Start-
ing Failure.> Step Check Yes No

EN(H4SO)-67
ENGINE (DIAGNOSTIC)
Diagnostics for Engine Starting Failure
E: FUEL PUMP CIRCUIT
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode ERATION, Clear Memory Mode.> and Inspection Mode tion Mode.>.
WIRING DIAGRAM:
EN-02382
B72B46
R15
F44
B99
B134
R58
3412
SBF-1
No.11SBF-4
E
1
2 4
B72
F44
B61
B46
R58R57R15
SBF-5
2134
4M14 1
B134ECM
341213
4562
12345678
1234567891011121314151617181920212223242526272829303132333435
BATTERY IGNITION
SWITCH
FUEL PUMP
RELAY
FUEL PUMP
7
B99
R7
B97
R186
LHD
LHDRHD
RHD
B97
12345678
RHD
LHD
LHD
RHD
E
123
45678

EN(H4SO)-68
ENGINE (DIAGNOSTIC)
Diagnostics for Engine Starting Failure
Step Check Yes No
1 CHECK OPERATING SOUND OF FUEL
PUMP.
Check that the fuel pump is in operation for two
seconds when turning the ignition switch to
ON.
N
OTE:
Fuel pump operation can also be executed us-
ing Subaru Select Monitor.
Refer to “Compulsory Valve Operation Check
Mode” for procedures. Compulsory Valve Operation Check Mode.>Does the fuel pump produce
operating sound?Check the fuel
injector circuit.
EN(H4SO)-70,
FUEL INJECTOR
CIRCUIT, Diag-
nostics for Engine
Starting Failure.>Go to step 2.
2 CHECK GROUND CIRCUIT OF FUEL PUMP.
1) Turn the ignition switch to OFF.
2) Remove the fuel pump access hole lid.
3) Disconnect the connector from fuel pump.
4) Measure the resistance of harness connec-
tor between fuel pump and chassis ground.
Connector & terminal
(R58) No. 4 — Chassis ground:Is the resistance less than 5
Ω?Go to step 3.Repair harness
and connector.
N
OTE:
In this case repair
the following:
 Open circuit in
harness between
fuel pump connec-
tor and chassis
grounding terminal
 Poor contact in
coupling connector
3 CHECK POWER SUPPLY TO FUEL PUMP.
1) Turn the ignition switch to ON.
2) Measure the voltage of power supply circuit
between fuel pump connector and chassis
ground.
Connector & terminal
(R58) No. 1 (+) — Chassis ground (
−):Is the voltage more than 10 V? Replace the fuel
pump. FU(H4SO)-55,
Fuel Pump.>Go to step 4.
4 CHECK HARNESS BETWEEN FUEL PUMP
AND FUEL PUMP RELAY CONNECTOR.
1) Turn the ignition switch to OFF.
2) Measure the resistance of harness connec-
tor between fuel pump and fuel pump relay.
Connector & terminal
(R58) No. 1 — (B46) No. 4:Is the resistance less than 1
Ω?Go to step 5.Repair harness
and connector.
N
OTE:
In this case repair
the following:
 Open circuit in
harness between
fuel pump connec-
tor and chassis
grounding terminal
 Poor contact in
coupling connector
5 CHECK HARNESS BETWEEN FUEL PUMP
AND FUEL PUMP RELAY CONNECTOR.
Measure the resistance of harness between
fuel pump and fuel pump relay connector.
Connector & terminal
(R58) No. 1 — Chassis ground:Is the resistance more than 1
MΩ?Go to step 6.Repair short circuit
in harness
between fuel pump
and fuel pump
relay connector.
6 CHECK FUEL PUMP RELAY.
1) Disconnect the connectors from fuel pump
relay and main relay.
2) Remove the fuel pump relay and main relay
with bracket.
3) Connect the battery to fuel pump relay con-
nector terminals No. 1 and No. 3.
4) Measure the resistance between connector
terminals of fuel pump relay.
Te r m i n a l s
No. 2 — No. 4:Is the resistance less than 10
Ω?Go to step 7.Replace the fuel
pump relay. to FU(H4SO)-55,
Fuel Pump.>

EN(H4SO)-69
ENGINE (DIAGNOSTIC)
Diagnostics for Engine Starting Failure
7 CHECK HARNESS BETWEEN ECM AND
FUEL PUMP RELAY CONNECTOR.
1) Disconnect the connector from ECM.
2) Measure the resistance of harness
between ECM and fuel pump relay connector.
Connector & terminal
(B134) No. 26 — (B46) No. 3:Is the resistance less than 1
Ω?Go to step 8.Repair open circuit
in harness
between ECM and
fuel pump relay
connector.
8 CHECK POOR CONTACT.
Check poor contact in ECM connector.Is there poor contact in ECM
connector?Repair the poor
contact in ECM
connector.Check the fuel
injector circuit.
EN(H4SO)-70,
FUEL INJECTOR
CIRCUIT, Diag-
nostics for Engine
Starting Failure.> Step Check Yes No

EN(H4SO)-70
ENGINE (DIAGNOSTIC)
Diagnostics for Engine Starting Failure
F: FUEL INJECTOR CIRCUIT
CAUTION:
 Check or repair only faulty parts.
 After repair or replacement of faulty parts, conduct Clear Memory Mode ERATION, Clear Memory Mode.> and Inspection Mode tion Mode.>.
WIRING DIAGRAM:
EN-02383
B21
12345678910111213141516
E6E17
E5E16
12
12121212
2223348
91101112
ECM
B134
E5E16E6E17
B21
E2
FUEL INJECTOR
No. 1FUEL INJECTOR
No. 2FUEL INJECTOR
No. 3FUEL INJECTOR
No. 4
BATTERY
F44B61
SBF-5
B47 MAIN RELAY
12
35
46
B47
34
12
56
F44
12345678
B134
1234567891011121314151617181920212223242526272829303132333435
LHDLHD
RHDRHD
7