2004 SUBARU FORESTER engine

EN(H4DOTC 2.5)-165
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
AP:DTC P0600 SERIAL COMMUNICATION LINK
DTC DETECTING CONDITION:
Immediately at fault recognition
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode OPERATION, Clear Memory Mode.> and Inspection Mode 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 2.5)-166
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 connectors from TCM.
4) Measure the resistance between ECM and
TCM connectors.
Connector & terminal
(B137) No. 18 — (B55) No. 3:
(B137) No. 26 — (B55) No. 12:Is the resistance less than 1
Ω?Go to step 2.Repair the harness
and 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 harness
and connector.
3 CHECK HARNESS BETWEEN ECM AND
TCM.
Check the resistance between ECM connec-
tors.
Connector & terminal
(B137) No. 18 — (B137) No. 26:Is the resistance more than 1
MΩ?Go to step 4.Repair the harness
and connector.
4 CHECK AT SYSTEM CONDITION.
Perform the diagnosis for AT using Subaru
Select Monitor.Is DTC P1718 displayed? Check AT system. Replace the ECM.

EN(H4DOTC 2.5)-167
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
AQ:DTC P0604 INTERNAL CONTROL MODULE READ ACCESS MEMORY
(RAM) 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 OPERATION, Clear Memory Mode.> and Inspection Mode Inspection Mode.>.

EN(H4DOTC 2.5)-168
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
WIRING DIAGRAM:
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 2.5)-
41, Engine Con-
trol Module
(ECM).>Temporary poor
contact occurs.
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)-169
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
AR:DTC P0605 INTERNAL CONTROL MODULE READ ONLY MEMORY (ROM)
ERROR
NOTE:
For the diagnostic procedure, refer to DTC P0607. MODULE PERFORMANCE, Diagnostic Procedure with Diagnostic Trouble Code (DTC).>

EN(H4DOTC 2.5)-170
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
AS:DTC P0607 CONTROL MODULE PERFORMANCE
DTC DETECTING CONDITION:
Immediately at fault recognition
TROUBLE SYMPTOM:
 Erroneous idling
 Poor driving performance
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode OPERATION, Clear Memory Mode.> and Inspection Mode Inspection Mode.>.

EN(H4DOTC 2.5)-171
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
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)-172
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
AT:DTC P0638 THROTTLE ACTUATOR CONTROL RANGE/PERFORMANCE
(BANK 1)
NOTE:
For diagnostic procedure, refer to DTC P2101. TUATOR CONTROL MOTOR CIRCUIT RANGE/PERFORMANCE, Diagnostic Procedure with Diagnostic
Trouble Code (DTC).>
Step Check Yes No
1 CHECK INPUT VOLTAGE OF ECM.
1) Turn the ignition switch to ON.
2) Measure the voltage between ECM con-
nector and ground.
Connector & terminal
(B135) No. 5 (+) — Chassis ground (
−):
(B135) No. 6 (+) — Chassis ground (
−):Is the voltage 10 — 13 V? Go to step 2.Repair open or
ground short cir-
cuit of power sup-
ply circuit.
2 CHECK INPUT VOLTAGE OF ECM.
1) Start the engine.
2) Measure the voltage between ECM con-
nector and ground.
Connector & terminal
(B135) No. 5 (+) — Chassis ground (
−):
(B135) No. 6 (+) — Chassis ground (
−):Is the voltage 13 — 15 V? Go to step 3.Repair open or
ground short cir-
cuit of power sup-
ply circuit.
3 CHECK ECM GROUND HARNESS.
Measure the voltage between ECM connector
and ground.
Connector & terminal
(B137) No. 1 (+) — Chassis ground (
−):
(B137) No. 2 (+) — Chassis ground (
−):Is the voltage less than 1 V? Repair the poor
contact in ECM
connector.
Replace the ECM
if defective.Further tighten the
engine ground ter-
minal.