2004 SUBARU FORESTER engine

EN(H4DOTC 2.5)-53
ENGINE (DIAGNOSTIC)
Malfunction Indicator Light
Step Check Yes No
1 CHECK TEST MODE CONNECTOR.
1) Disconnect the test mode connectors
2) Turn the ignition switch to ON.Does the malfunction indicator
light blink?Go to step 2.System is in good
order.
N
OTE:
Malfunction indica-
tor light blinks at a
cycle of 3 Hz when
test mode connec-
tor is connected.
2 CHECK HARNESS BETWEEN ECM CON-
NECTOR AND ENGINE GROUND TERMI-
NAL.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from ECM.
3) Measure the resistance of harness
between ECM connector and chassis ground.
Connector & terminal
(B137) No. 15 — Chassis ground:Is the resistance less than 5
Ω?Repair the short
circuit in harness
between ECM and
test mode connec-
tor.Replace the ECM.
FU(H4DOTC 2.5)-
41, Engine Con-
trol Module
(ECM).>

EN(H4DOTC 2.5)-54
ENGINE (DIAGNOSTIC)
Diagnostics for Engine Starting Failure
16.Diagnostics for Engine Starting Failure
A: PROCEDURE
1. Check for fuel amount.
↓
2. Inspection of starter motor circuit. Failure.>
↓
3. Inspection of ECM power supply and ground line. LINE OF ENGINE CONTROL MODULE (ECM), Diagnostics for Engine Starting Failure.>
↓
4. Inspection of ignition control system. Starting Failure.>
↓
5. Inspection of fuel pump circuit.
↓
6. Inspection of fuel injector circuit. Failure.>

EN(H4DOTC 2.5)-55
ENGINE (DIAGNOSTIC)
Diagnostics for Engine Starting Failure
B: STARTER MOTOR CIRCUIT
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode OPERATION, Clear Memory Mode.> and Inspection Mode Inspection Mode.>.
WIRING DIAGRAM:
EN-02311
BATTERY
INHIBITOR SWITCH
IGNITION
SWITCH
STARTER
MOTOR
SBF-4SBF-1
B72
B72
B14
B137
ECM
EE
1
3
D8
3412
B137
T3B12MT
AT
AT
MT
1112712
PR
N
D3
21
T7
B12
123
8
9
10
4
11
1256
7
T7
123
8910411 1256
7567
82 1
94 310
22 23 11 12 13 14 15
24 25
2616 17
18 19 20 21
27 28 29 30 31

EN(H4DOTC 2.5)-56
ENGINE (DIAGNOSTIC)
Diagnostics for Engine Starting Failure
Step Check Yes No
1 CHECK BATTERY.
Check the battery voltage.Is the voltage more than 12 V? Go to step 2.Charge or replace
the battery.
2 CHECK OPERATION OF STARTER MOTOR.Does the starter motor oper-
ate?Check ECM power
supply and ground
line. EN(H4DOTC 2.5)-
57, CHECK
POWER SUPPLY
AND GROUND
LINE OF ENGINE
CONTROL MOD-
ULE (ECM), Diag-
nostics for Engine
Starting Failure.>Go to step 3.
3 CHECK INPUT SIGNAL FOR STARTER MO-
TOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from starter
motor.
3) Turn the ignition switch to START.
4) Measure the power supply voltage between
starter motor connector terminal and engine
ground.
Connector & terminal
(B14) No. 1 (+) — Engine ground (
−):
NOTE:
 For AT model, shift the select lever to “P” or
“N” range.
 For MT model, depress the clutch pedal.Is the voltage more than 10 V? Go to step 4.Go to step 5.
4 CHECK GROUND CIRCUIT OF STARTER
MOTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the terminal from starter motor.
3) Measure the resistance of ground cable
between ground cable terminal and engine
ground.Is the resistance less than 5
Ω?Check the starter
motor. SC(H4SO)-6,
Starter.>Repair open circuit
of ground cable.
5 CHECK HARNESS BETWEEN BATTERY
AND IGNITION SWITCH CONNECTOR.
1) Disconnect the connector from ignition
switch.
2) Measure the power supply voltage between
ignition switch connector and chassis ground.
Connector & terminal
(B72) No. 1 (+) — Chassis ground (
−):Is the voltage more than 10 V? Go to step 6.Repair open circuit
in harness
between ignition
switch and bat-
tery, and check
fuse SBF No. 4
and SBF No. 1.
6 CHECK IGNITION SWITCH.
1) Disconnect the connector from ignition
switch.
2) Measure the resistance between ignition
switch terminals while turning the ignition
switch to START.
Te r m i n a l s
No. 1 — No. 3:Is the resistance less than 5
Ω?Repair the poor
contact in ignition
switch.Replace the igni-
tion switch.

EN(H4DOTC 2.5)-57
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 OPERATION, Clear Memory Mode.> and Inspection Mode Inspection Mode.>.
WIRING DIAGRAM:
EN-02356
B72
B135
3412
BATTERY MAIN RELAY
SBF-4 SBF-1SBF-5
B72
D16 D7
B12
A6
A7
B1
B4
D1
D2
A34B5
B6
B19
D14
No.11
B47
E2 B21 1 2 3 5 6 4
ECM
E
E
1 4
B134
B135
B137 A:
B:
D:
14133
15
16
34 12
56123
4
56
78
91011 12
1314 15 16
B134 B21 B47B137 A: D:
B: IGNITION
SWITCH
56 7
82 1
94 310
24 22 23 25 11 12 13 14 15
26 27
2816 17
18 19 20 21
33 34 29
32 30 31
567
82 1
94 310
24 22 23 2511 12 13 14 15
26 27
2816 17 18 19
20 21
29 30 31 32 33 34 35
567
82 1
94 310
22 23 11 12 13 14 15
24 25
2616 17
18 19 20 21
27 28 29 30 31

EN(H4DOTC 2.5)-58
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. 6 — Chassis ground:
(B134) No. 7 — Chassis ground:
(B134) No. 34 — Chassis ground:
(B135) No. 1 — Chassis ground:
(B135) No. 4 — Chassis ground:
(B135) No. 12 — Chassis ground:
(B137) No. 1 — Chassis ground:
(B137) No. 2 — Chassis ground:
(B137) No. 7 — Chassis ground: Is the resistance less than 5
Ω?Go to step 3.Repair open circuit
in harness
between ECM con-
nector and engine
ground terminal.
3 CHECK INPUT VOLTAGE OF ECM.
Measure the voltage between ECM connector
and chassis ground.
Connector & terminal
(B135) No. 19 (+) — Chassis ground (
−):
(B137) No. 14 (+) — 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 MAIN RELAY.
Measure the voltage between main relay con-
nector and chassis ground.
Connector & terminal
(B47) No. 1 (+) — Chassis ground (
−):
(B47) No. 5 (+) — Chassis ground (
−):
(B47) No. 6 (+) — Chassis ground (
−):Is the voltage more than 10 V? Go to step 5.Repair open or
ground short circuit
in harness of power
supply circuit.
5 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. 5 (+) — Chassis ground (
−):
(B135) No. 6 (+) — Chassis ground (
−):
(B137) No. 16 (+) — Chassis ground (
−):Is the voltage more than 10 V? Check ignition
control system.
EN(H4DOTC 2.5)-
59, IGNITION
CONTROL SYS-
TEM, Diagnostics
for Engine Start-
ing Failure.>Repair open or
ground short circuit
in harness
between ECM con-
nector and main
relay connector.

EN(H4DOTC 2.5)-59
ENGINE (DIAGNOSTIC)
Diagnostics for Engine Starting Failure
D: IGNITION CONTROL SYSTEM
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode OPERATION, Clear Memory Mode.> and Inspection Mode Inspection Mode.>.
WIRING DIAGRAM:
EN-02357
IGNITION
SWITCH
SBF-4SBF-1
B72
B135
18
17
16
15
ECM
No.11
E
E
41
E2 B21
E31
E31
E32
E33
E34IGNITION COIL
No.1IGNITION COIL
No.2IGNITION COIL
No.3IGNITION COIL
No.4
E32E33E34
123
123
4
56
78
9
1011 12
1314 15 16
B21B135B72
34
12
3
1
23
1
2
5 4
6
7
8
3
1
23
1
2
567
82 1
94 310
24 22 23 2511 12 13 14 15
26 27
2816 17 18 19
20 21
29 30 31 32 33 34 35
BATTERY

EN(H4DOTC 2.5)-60
ENGINE (DIAGNOSTIC)
Diagnostics for Engine Starting Failure
Step Check Yes No
1 CHECK SPARK PLUG CONDITION.
1) Remove the spark plug. IG(H4DOTC)-6, INSTALLATION, Spark Plug.>
2) Check the spark plug condition. IG(H4DOTC)-6, INSPECTION, Spark Plug.>Is the spark plug’s status OK? Go to step 2.Replace the spark
plug.
2 CHECK IGNITION SYSTEM FOR SPARKS.
1) Connect the spark plug to ignition coil.
2) Release the fuel pressure. FU(H4DOTC 2.5)-45, RELEASING OF FUEL
PRESSURE, OPERATION, Fuel.>
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(H4DOTC 2.5)-
62, FUEL PUMP
CIRCUIT, Diag-
nostics for Engine
Starting Failure.>Go to step 3.
3 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
(E31) No. 3 (+) — Engine ground (
−):
(E32) No. 3 (+) — Engine ground (
−):
(E33) No. 3 (+) — Engine ground (
−):
(E34) No. 3 (+) — Engine ground (
−):Is the voltage more than 10 V? Go to step 4.Repair the harness
and connector.
N
OTE:
In this case repair
the following:
 Open circuit in
harness between
ignition coil & igni-
tor ASSY, and igni-
tion switch
connector
 Poor contact in
coupling connector
4 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
(E31) No. 2 — Engine ground:
(E32) No. 2 — Engine ground:
(E33) No. 2 — Engine ground:
(E34) No. 2 — Engine ground:Is the resistance less than 5
Ω?Go to step 5.Repair the 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
5 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
(B135) No. 15 — (E34) No. 1:
(B135) No. 16 — (E33) No. 1:
(B135) No. 17 — (E32) No. 1:
(B135) No. 18 — (E31) No. 1:Is the resistance less than 1
Ω?Go to step 6.Repair the harness
and connector.
N
OTE:
In this case repair
the following:
 OPEN CIR-
CUIT IN HAR-
NESS BETWEEN
ECM AND IGNI-
TION COIL &
IGNITOR ASSY
CONNECTOR.
 Poor contact in
coupling connector