Subaru Legacy (2005 year). Manual - part 222

EN(H4SO 2.5)(diag)-173

ENGINE (DIAGNOSTICS)

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

Step

Check

Yes

No

1

CHECK OPTION CODE.

Is the option code EC, EK, EH, 
ER or K4?

Go to step 2.

Refer to EN(H4SO 
2.0) section. <Ref. 
to EN(H4SO 
2.0)(diag)-64, List 
of Diagnostic Trou-
ble Code (DTC).>

NOTE:
Fuel injection sys-
tem for KA and KS
model is the same
as 2.0 L model.

2

CHECK HARNESS BETWEEN IGNITION 
SWITCH AND ECM.
1) Disconnect the connector from ECM.
2) Measure the voltage between ECM and 
chassis ground.

Connector & terminal

(B135) No. 32 (+) — Chassis ground (

−

):

Is the voltage more than 10 V? Repair the battery 

short circuit of har-
ness between igni-
tion switch and 
ECM.

Repair the poor 
contact in ECM.

EN(H4SO 2.5)(diag)-174

ENGINE (DIAGNOSTICS)

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

AR:DTC P0519 IDLE AIR CONTROL SYSTEM PERFORMANCE

DTC DETECTING CONDITION:
Immediately at fault recognition
TROUBLE SYMPTOM:
Engine keeps running at higher speed than specified idle speed.

CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode <Ref. to EN(H4SO 2.5)(diag)-
40, Clear Memory Mode.> and Inspection Mode <Ref. to EN(H4SO 2.5)(diag)-33, Inspection Mode.>.

AS:DTC P0600 SERIAL COMMUNICATION LINK

NOTE:
For the diagnostic procedure, refer to LAN section. <Ref. to LAN(diag)-2, Basic Diagnostic Procedure.>

Step

Check

Yes

No

1

CHECK OPTION CODE.

Is the option code EC, EK, EH, 
ER or K4?

Go to step 2.

Refer to EN(H4SO 
2.0) section. <Ref. 
to EN(H4SO 
2.0)(diag)-64, List 
of Diagnostic Trou-
ble Code (DTC).>

NOTE:
Fuel injection sys-
tem for KA and KS
model is the same
as 2.0 L model.

2

CHECK ANY OTHER DTC ON DISPLAY.

Is any other DTC displayed?

Check DTC using 
“List of Diagnostic 
Trouble Code 
(DTC)”. <Ref. to 
EN(H4SO 
2.5)(diag)-69, List 
of Diagnostic Trou-
ble Code (DTC).>

NOTE:
In this case, it is
not necessary to
inspect DTC
P0519.

Go to step 3.

3

CHECK AIR INTAKE SYSTEM.
1) Turn the ignition switch to ON.
2) Start and idle the engine.
3) Check the following items.
• Loose installation of intake manifold and 
throttle body
• Cracks of intake manifold gasket and throttle 
body gasket
• Disconnections of vacuum hoses

Is there any fault in air intake 
system?

Repair air suction 
and leaks.

Go to step 4.

4

CHECK ELECTRONIC THROTTLE CON-
TROL.
1) Turn the ignition switch to OFF.
2) Remove the electronic throttle control.
3) Check the electronic throttle control.

Are foreign matters found 
inside the electronic throttle 
control?

Remove foreign 
matters from the 
electronic throttle 
control.

Perform the diag-
nosis of DTC 
P2101.

EN(H4SO 2.5)(diag)-175

ENGINE (DIAGNOSTICS)

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

AT:DTC P0604 INTERNAL CONTROL MODULE RANDOM 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 <Ref. to EN(H4SO 2.5)(diag)-
40, Clear Memory Mode.> and Inspection Mode <Ref. to EN(H4SO 2.5)(diag)-33, Inspection Mode.>.
WIRING DIAGRAM:
• EC, EK, EH, ER and K4 model

• KA and KS model

NOTE:
Fuel injection system for KA and KS model is the same as 2.0 L model. Refer to EN(H4SO 2.0) section.

EN-03511

SBF-6

MAIN SBF

SBF-7

B72

B6

B5

A6

D2

A7

B12

D3

D7

D1

B19

No.12

B47

E2

B21

6

5

E

E

3

6

B134

B135

A:

D: B137

B:

B4

52

37

36

34

47

3

4

1

2

5

6

B47

No.13

B1

35

B134

5

6

7

8

2

1

9

4

3

10

24

22 23

25

11 12 13 14 15

26 27

28

16 17

18 19 20 21

33 34

29

32

30 31

B135

5

6

7

8

2

1

9

4

3

10

24

22 23

25

11 12 13 14 15

26 27

28

16 17 18 19

20 21

29 30 31

32 33

34 35

B137

5

6

7

8

2

1

9

4

3

10

22 23

11 12 13 14 15

24 25

26

16 17

18 19 20 21

27

28 29

30 31

B21

1 2 3 4

12 13 14 15

5 6 7 8

16 17 18 19

9 10 11

20 21 22

23 24 25 26 27 28 29 30 31 32 33

35

34

37

36

39

38

41

40

43

42

44

45

47

46

49

48

51

50

53

52

54

B72

1

3

4 5 6

2

A:

B:

D:

1
2

1

*

2

*

4

3

ECM

1

*

2

*

MAIN RELAY

TO IGNITION COIL

IGNITION
SWITCH

BATTERY

LHD WITH IMMOBILIZER: D16
LHD WITHOUT IMMOBILIZER: D17
RHD : D16 

LHD WITH IMMOBILIZER: D14
LHD WITHOUT IMMOBILIZER: D15
RHD : D14

EN(H4SO 2.5)(diag)-176

ENGINE (DIAGNOSTICS)

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

AU:DTC P0605 INTERNAL CONTROL MODULE READ ONLY MEMORY (ROM) 

ERROR

NOTE:
For the diagnostic procedure, refer to DTC P0607. <Ref. to EN(H4SO 2.5)(diag)-177, DTC P0607 CON-
TROL MODULE PERFORMANCE, Diagnostic Procedure with Diagnostic Trouble Code (DTC).>

Step

Check

Yes

No

1

CHECK OPTION CODE.

Is the option code EC, EK, EH, 
ER or K4?

Go to step 2.

Refer to EN(H4SO 
2.0) section. <Ref. 
to EN(H4SO 
2.0)(diag)-64, List 
of Diagnostic Trou-
ble Code (DTC).>

NOTE:
Fuel injection sys-
tem for KA and KS
model is the same
as 2.0 L model.

2

CHECK ANY OTHER DTC ON DISPLAY.

Is any other DTC displayed?

Inspect the rele-
vant DTC using 
“List of Diagnostic 
Trouble Code 
(DTC)”. <Ref. to 
EN(H4SO 
2.5)(diag)-69, List 
of Diagnostic Trou-
ble Code (DTC).>

Temporary poor 
contact occurs.