2004 SUBARU FORESTER engine

EN(H4DOTC)-227
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step Check Yes No
1 CHECK HARNESS BETWEEN GENERATOR
AND ECM CONNECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from generator
and ECM.
3) Measure the resistance of harness
between generator connector and engine
ground.
Connector & terminal
(F26) No. 3 — Engine ground:Is the resistance more than 1
MΩ?Go to step 2.Repair ground
short circuit in har-
ness between
ECM and purge
control solenoid
valve connector.
2 CHECK HARNESS BETWEEN GENERATOR
AND ECM CONNECTOR.
Measure the resistance of harness between
ECM and generator.
Connector & terminal
(B134) No. 22 — (F26) No. 3:Is the resistance less than 1
Ω?Repair poor con-
tact connector.Repair open circuit
in harness
between ECM and
generator connec-
tor.
N
OTE:
In this case repair
the following:
 Open circuit in
harness between
ECM and genera-
tor connector
 Poor contact in
coupling connector

EN(H4DOTC)-228
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
BQ:DTC P0600 SERIAL COMMUNICATION LINK
DTC DETECTING CONDITION:
Immediately at fault recognition
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode ERATION, Clear Memory Mode.> and Inspection Mode .
WIRING DIAGRAM:
AT-01524
18
263
12
B55
B137
ECM
B55 TCM
B137
12
7
8956 3410 11 12
19 20 2113 14 15 16
17 1822
23
24
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
TWISTED WIRE

EN(H4DOTC)-229
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step Check Yes No
1 CHECK HARNESS BETWEEN ECM AND
TCM.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from ECM.
3) Disconnect the connector from TCM.
4) Measure the resistance between connec-
tors of ECM and TCM.
Connector & terminal
(B137) No. 18 — (B55) No. 3:
(B137) No. 26 — (B54) No. 12:Is the resistance less than 1
Ω?Go to step 2.Repair the har-
ness connector.
2 CHECK HARNESS BETWEEN ECM AND
TCM.
Measure the resistance between ECM connec-
tor and chassis ground.
Connector & terminal
(B137) No. 18 — Chassis ground:
(B137) No. 26 — Chassis ground:Is the resistance more than 1
MΩ?Go to step 3.Repair the har-
ness connector.
3 CHECK HARNESS BETWEEN ECM AND
TCM.
Measure the resistance of ECM connectors.
Connector & terminal
(B137) No. 18 — (B137) No. 26:Is the resistance more than 1
MΩ?Go to step 4.Repair the har-
ness connector.
4 CHECK AT SYSTEM STATUS.
Check the AT using Subaru Select Monitor.Does the Subaru Select Moni-
tor display DTC P1718?Inspect the AT sys-
tem.Replace the ECM.
FU(H4DOTC)-50,
Engine Control
Module (ECM).>

EN(H4DOTC)-230
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
BR:DTC P0604 INTERNAL CONTROL MODULE READ ONLY MEMORY (ROM)
ERROR
DTC DETECTING CONDITION:
Immediately at fault recognition
TROUBLE SYMPTOM:
 Engine does not start.
 Engine stalls.
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode ERATION, Clear Memory Mode.> and Inspection Mode .
WIRING DIAGRAM:
LHD model
EN-02312
F74
B72
34
12
BATTERYIGNITION
SWITCH MAIN RELAY
SBF-4SBF-1
SBF-5
B72 TO FRONT OXYGEN (A/F) SENSOR
D16 D7
B12
A6
A7
B4
B1
D1
D2
A34B5
D6
B19
D14
No.11
B61F44
B47
B100
F2
E3 F60 1 2 3 5 6 4
ECM
EE
14
B134
B137 B135 A :
B :
C :B136
D :
14
7
3412
56
123
4
56
78
9
1011 12
1314 15 16
F60B47
B137
F2
B100F2
11
10
20
8
9 13
14
3
15
16
B135
F44
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
12345678
34
12 8910 11
12 13 14 15 16 17 18 19 20 21 22 23 2456 71234 5678910 11 12 13 14 15 16 17 18 19 20
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
F74 B200
MT
MT
B134
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
B136
56
782 1
94 310
24 22 23 2511 12 13
1415
26 27
2816
17 18 19 20 21
33 34 29
32 30
31 35

EN(H4DOTC)-231
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
RHD model
Step Check Yes No
1 CHECK ANY OTHER DTC ON DISPLAY.Does the Subaru Select Moni-
tor or OBD-II general scan tool
indicate DTC P0604?Replace the ECM.
FU(H4DOTC)-50,
Engine Control
Module (ECM).>Temporary poor
contact occurs.
B72B136
34
12
BATTERYIGNITION
SWITCH MAIN RELAY
SBF-4SBF-1
SBF-5
B72 DATA LINK CONNECTOR
D16 B4
B1
A6
A7
D7
B12
D1
D2
C19B5
B6
B19
D14
No.11B47
E2 B21 1 2 3 5 6 4
ECM
14
B134
B135
B136 A :
B :
C :
B137
D :
15
3
16 14 13
3412
56
123
4
56
78
9
1011 12
1314 15 16
B134B21
B47B135B137
EN-02313
E
E E
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
A34
MTMT
56
782 1
94 310
24 22 23 2511 12 13
1415
26 27
2816
17 18 19 20 21
33 34 29
32 30
31 35
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
D :
B :
C :
A :

EN(H4DOTC)-232
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
BS:DTC P0691 COOLING FAN 1 CONTROL CIRCUIT LOW
DTC DETECTING CONDITION:
Two consecutive driving cycles with fault
TROUBLE SYMPTOM:
 Radiator fan does not operate properly.
 Over-heating
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode ERATION, Clear Memory Mode.> and Inspection Mode spection Mode.>.

EN(H4DOTC)-233
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
WIRING DIAGRAM:
EN-02337
No.18
No.17
EE
SBF-4
SBF-1
F17
B135 ECM
25
24F16
F16B72F2F27
F17
3412
1
2
SUB FAN
MOTOR
M
1
2
MAIN FAN
MOTOR
M
BATTERY
IGNITION
SWITCHB72
41
1234 5678910 11 12 13 14 15 16 17 18 19 203132333435
36
56789
1011121314
1516171819
2021222324
2526272829
1230
34
20A
F27 FAN
MODE
RELAY
A/C RELAY HOLDER
MAIN
FAN
RELAY SUB
FAN
RELAY
20A
29
25
27
28
30
34
32
317
5
9
2
1
4
3 8 6
B100F2
12B135
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
LHD : 10
RHD : 7
LHD : 11
RHD : 19 *
*1
2
*1
*2
: LHD
: RHD
F2
12345 678910
11
1219 20 21
13 14 15 1617
18 22

EN(H4DOTC)-234
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step Check Yes No
1 CHECK OUTPUT SIGNAL FROM ECM.
1) Turn the ignition switch to OFF.
2) Connect the test mode connector.
3) Turn the ignition switch to ON.
4) While operating the radiator fan relay, mea-
sure voltage between ECM terminal and
ground.
N
OTE:
Radiator fan relay operation can be executed
using Subaru Select Monitor.For procedure, re-
fer to “Compulsory Valve Operation Check
Mode”. Valve Operation Check Mode.>
Connector & terminal
(B135) No. 24 (+) — Chassis ground (
−):
(B135) No. 25 (+) — Chassis ground (
−):Does the voltage vary between
0 — 10 V?Repair the poor
contact in ECM
connector.Go to step 2.
2 CHECK GROUND SHORT CIRCUIT IN RADI-
ATOR FAN RELAY CONTROL CIRCUIT.
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
(B135) No. 24 — Chassis ground:
(B135) No. 25 — Chassis ground:Is the resistance more than 1
MΩ?Go to step 3.Repair ground
short circuit in
radiator fan relay
control circuit.
3 CHECK POWER SUPPLY FOR RELAY.
1) Remove the main fan relay 1 and sub fan
relay from A/C relay holder.
2) Turn the ignition switch to ON.
3) Measure the voltage between fuse and
relay box (F/B) connector and chassis ground.
Connector & terminal
(F27) No. 25 (+) — Chassis ground (
−):
(F27) No. 34 (+) — Chassis ground (
−):Is the voltage more than 10 V? Go to step 4.Repair open circuit
in harness
between ignition
switch and fuse
and relay box (F/B)
connector.
4 CHECK MAIN FAN RELAY 1.
1) Turn the ignition switch to OFF.
2) Measure the resistance of main fan relay 1
terminals.
Te r m i n a l s
No. 32 — No. 34:Is the resistance 87 — 107 Ω? Go to step 5.Replace the main
fan relay 1.
5 CHECK SUB FAN RELAY.
1) Turn the ignition switch to OFF.
2) Measure the resistance between sub fan
relay terminals.
Te r m i n a l s
No. 25 — No. 27:Is the resistance 87 — 107 Ω? Go to step 6.Replace the sub
fan relay.
6 CHECK OPEN CIRCUIT IN FAN RELAY
CONTROL CIRCUIT.
Measure the resistance of harness between
ECM and fan relay connector.
Connector & terminal
(B135) No. 24 — (F27) No. 27:
(B135) No. 25 — (F27) No. 32: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 fan relay
connector
 Poor contact in
coupling connector