Subaru Legacy IV (2008 year). Service manual - part 103

EN(H4SO)(diag)-15

Electrical Component Location

ENGINE (DIAGNOSTICS)

(1)

Pressure control solenoid valve

(3)

Drain valve

(4)

Drain filter

(2)

Canister

  

  

EN-05733

(1)

(2)

(3)

(4)

EN-02980

(1)

EN-02981

(4)

(3)

(2)

EN(H4SO)(diag)-16

Electrical Component Location

ENGINE (DIAGNOSTICS)

(1)

Inhibitor switch

(4)

Fuel pump relay

(7)

Radiator sub fan relay

(2)

Fuel pump

(5)

Electronic throttle control relay

(8)

Radiator main fan relay 2

(3)

Main relay

(6)

Radiator main fan relay 1

(9)

Starter

EN-05734

(3)

(2)

(7)

(8)

(6)

(9)

(1)

(4)

(5)

EN-06888

(1)

(2)

EN-05726

EN-03150

(3)

(4)

(5)

EN-06796

(6)

(8)

(7)

EN-02096

(9)

EN(H4SO)(diag)-17

Engine Control Module (ECM) I/O Signal

ENGINE (DIAGNOSTICS)

5. Engine Control Module (ECM) I/O Signal

A: ELECTRICAL SPECIFICATION

Contents

Connector 

No.

Terminal 

No.

Signal (V)

Note

Ignition SW ON

(engine OFF)

Engine ON

(idling)

Crankshaft 
position sensor

Signal (+)

B134

13

0

–7 — +7

Waveform

Signal (–)

B134

14

0

0

 — 

Shield

B134

24

0

0

 — 

Camshaft posi-
tion sensor

Signal (+)

B134

12

0

–7 — +7

Waveform

Signal (–)

B134

22

0

0

 — 

Shield

B134

24

0

0

 — 

Electronic throt-
tle control

Main

B134

18

0.64 — 0.72

Fully opened: 3.96

0.64 — 0.72

(After engine is 

warmed up.)

Fully closed: 0.6

Fully opened: 3.96

Sub

B134

28

1.51 — 1.58

Fully opened: 4.17

1.51 — 1.58

(After engine is 

warmed up.)

Fully closed: 1.48

Fully opened: 4.17

Power supply

B134

19

5

5

 — 

GND (sensor)

B134

29

0

0

 — 

Electronic throttle control motor 
(+)

B137

5

Duty waveform

Duty waveform

Drive frequency: 

500 Hz

Electronic throttle control motor 
(–)

B137

4

Duty waveform

Duty waveform

Drive frequency: 

500 Hz

Electronic throttle control motor 
power supply

B136

1

10 — 13

12 — 14

 — 

Electronic throttle control motor 
relay

B136

21

ON: 0

OFF: 10 — 13

ON: 0

OFF: 12 — 14

When ignition switch 

is turned to ON: ON

EN-05288

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

B136

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

35

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

TO A:

TO B: 

TO C: 

TO D: 

EN(H4SO)(diag)-18

Engine Control Module (ECM) I/O Signal

ENGINE (DIAGNOSTICS)

Accelerator 
pedal position 
sensor

Main sensor 
signal

B135

23

Fully closed: 1.0

Fully opened: 3.5

Fully closed: 1.0

Fully opened: 3.5

 — 

Main power 
supply

B135

21

5

5

 — 

GND 
(Main sensor)

B135

29

0

0

 — 

Sub sensor 
signal

B135

31

Fully closed: 1.0

Fully opened: 3.5

Fully closed: 1.0

Fully opened: 3.5

 — 

Sub power 
supply

B135

22

5

5

 — 

GND 
(Sub sensor)

B135

30

0

0

 — 

Rear oxygen 
sensor

Signal

B135

4

0

0 — 0.9

 — 

Shield

B135

1

0

0

 — 

Front oxygen 
(A/F) sensor 
heater

Signal 1

B136

3

10 — 13

1 — 14

Duty waveform

Signal 2

B136

2

10 — 13

1 — 14

Duty waveform

Rear oxygen sensor heater signal

B136

4

10 — 13

1 — 14

Duty waveform

Engine coolant temperature 
sensor

B134

34

1.0 — 1.4

1.0 — 1.4

After engine is 

warmed up.

Starter switch

B136

32

0

0

AT model

Cranking: 8 — 14

MT model

Cranking with the 

clutch pedal pressed: 

8 — 14

Starter relay control

B136

20

ON: 0.5 or less

OFF: 10 — 13

ON: 0.5 or less

OFF: 12 — 14

 — 

A/C switch

B136

24

ON: 10 — 13

OFF: 0

ON: 12 — 14

OFF: 0

 — 

Ignition switch

B135

19

10 — 13

12 — 14

 — 

Neutral position switch

B136

31

ON: 0

OFF: 12

r0.5

AT model: Switch is 

ON when select lever 

is shifted into “P” 

range or “N” range.

MT model: Switch is 

ON when the shift 

lever is in neutral.

Delivery (test) mode connector

B135

27

10 — 13

13 — 14

When connected: 0

Knock sensor

Signal

B134

15

2.5

2.5

 — 

Shield

B134

25

0

0

 — 

Back-up power supply

B135

5

10 — 13

12 — 14

Ignition switch “OFF”: 

10 — 13

Control module power supply

B134

7

10 — 13

12 — 14

 — 

B135

2

10 — 13

12 — 14

 — 

Ignition control

#1, #2

B137

18

0

1 — 3.4

Waveform

#3, #4

B137

19

0

1 — 3.4

Waveform

Fuel injector

#1

B137

8

10 — 13

1 — 14

Waveform

#2

B137

9

10 — 13

1 — 14

Waveform

#3

B137

10

10 — 13

1 — 14

Waveform

#4

B137

11

10 — 13

1 — 14

Waveform

Contents

Connector 

No.

Terminal 

No.

Signal (V)

Note

Ignition SW ON

(engine OFF)

Engine ON

(idling)