Subaru Legacy IV (2008 year). Service manual — part 299

EN(H4DOTC)(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

—

Rear oxygen
sensor

Signal

B135

4

0

0 — 0.9

—

Shield

B135

1

0

0

—

Ground
(sensor)

B135

30

0

0

—

Front oxygen
(A/F) sensor
heater

Signal 1

B136

3

—

—

Waveform

Signal 2

B136

2

—

—

Waveform

Rear oxygen sensor heater signal

B136

4

0 — 13

12 — 14

Waveform

Engine coolant
temperature
sensor

Signal

B134

34

1.0 — 1.4

1.0 — 1.4

After engine is

warmed up.

Ground
(sensor)

B134

29

0

0

After engine is

warmed up.

Air flow sensor

Signal

B135

26

—

0.3 — 4.5

—

Shield

B135

35

0

0

—

Ground

B135

34

0

0

—

Intake air temperature sensor
signal

B135

18

0.3 — 4.6

0.3 — 4.6

—

Wastegate control solenoid
valve

B137

27

0 or 10 — 13

0 or 12 — 14

Waveform

Starter switch

B136

32

0

0

Cranking: 8 — 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 (AT / MT)

B136

31

ON: 0

OFF: 10 — 13

ON: 0

OFF: 12 — 14

—

Delivery (test) mode connector

B135

27

10 — 13

13 — 14

When connected: 0

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(H4DOTC)(diag)-18

Engine Control Module (ECM) I/O Signal

ENGINE (DIAGNOSTICS)

Knock sensor

Signal

B134

15

2.8

2.8

—

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

—

Sensor power supply

B134

19

5

5

—

Ignition control

#1

B137

18

0

12 — 14

Waveform

#2

B137

19

0

12 — 14

Waveform

#3

B137

20

0

12 — 14

Waveform

#4

B137

21

0

12 — 14

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

Fuel pump con-
trol unit

Signal 1

B135

33

10 — 13

12 — 14

—

Signal 2

B136

12

0 or 5

0 or 5

Waveform

A/C relay control

B136

9

ON: 0.5 or less

OFF: 10 — 13

ON: 0.5 or less

OFF: 12 — 14

—

Radiator fan relay 1 control

B136

18

ON: 0.5 or less

OFF: 10 — 13

ON: 0.5 or less

OFF: 12 — 14

—

Radiator fan relay 2 control

B136

29

ON: 0.5 or less

OFF: 10 — 13

ON: 0.5 or less

OFF: 12 — 14

Model with A/C only

Malfunction indicator light

B136

11

—

—

Light “ON”: 1 or less

Light “OFF”: 10 — 14

Engine speed output

B136

22

—

0 — 13 or more

Waveform

Purge control solenoid valve 1

B137

29

ON: 1 or less

OFF: 10 — 13

ON: 1 or less

OFF: 12 — 14

Waveform

Purge control solenoid valve 2

B136

7

ON: 1 or less

OFF: 10 — 13

ON: 1 or less

OFF: 12 — 14

Waveform

Manifold abso-
lute pressure
sensor

Signal

B134

6

1.7 — 2.4

1.1 — 1.6

—

Power supply

B134

19

5

5

Ground
(sensor)

B134

29

0

0

Power steering oil pressure
switch

B134

33

10 — 13

ON: 0

OFF: 12 — 14

—

Front oxygen (A/F) sensor signal
(+)

B135

9

2.8 — 3.2

2.8 — 3.2

—

Front oxygen (A/F) sensor signal
(–)

B135

8

2.4 — 2.7

2.4 — 2.7

—

Front oxygen (A/F) sensor
shield

B135

1

0

0

—

SSM communication line

B136

16

1 or less

mo 4 or

more

1 or less

mo 4 or

more

—

Intake camshaft position sensor
(LH)

B134

21

0 or 5

0 or 5

Waveform

Intake camshaft position sensor
(RH)

B134

11

0 or 5

0 or 5

Waveform

Intake camshaft position sensor
ground

B134

22

0

0

—

Contents

Connector

No.

Terminal

No.

Signal (V)

Note

Ignition SW ON

(engine OFF)

Engine ON

(idling)

EN(H4DOTC)(diag)-19

Engine Control Module (ECM) I/O Signal

ENGINE (DIAGNOSTICS)

Electric
throttle 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

—

Ground
(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

Intake AVCS
solenoid (LH)

Signal (+)

B137

15

ON: 10 — 13

OFF: 0

ON: 12 — 14

OFF: 0

—

Signal (–)

B137

14

0

0

—

Intake AVCS
solenoid (RH)

Signal (+)

B137

17

ON: 10 — 13

OFF: 0

ON: 12 — 14

OFF: 0

—

Signal (–)

B137

16

0

0

—

Accelerator
pedal position
sensor

Main sensor
signal

B135

23

Fully closed: 1

Fully opened: 3.3

Fully closed: 1

Fully opened: 3.3

—

Main power
supply

B135

21

5

5

—

Ground
(main sensor)

B135

29

0

0

—

Shield

B136

6

0

0

—

Sub sensor
signal

B135

31

Fully closed: 1

Fully opened: 3.3

Fully closed: 1

Fully opened: 3.3

—

Sub power
supply

B135

22

5

5

—

Ground
(sub sensor)

B135

30

0

0

—

Starter relay

B136

20

ON: 0

OFF: 10 — 13

ON: 0

OFF: 12 — 14

ON: cranking

A/C middle pressure switch

B136

33

ON: 0

OFF: 10 — 13

ON: 0

OFF: 12 — 14

—

Clutch switch

B136

25

When clutch pedal is

depressed: 0

When clutch pedal is

released: 10 — 13

When clutch pedal is

depressed: 0

When clutch pedal is

released: 12 — 14

—

Brake switch 1

B135

20

When brake pedal is

depressed: 0

When brake pedal is

released: 10 — 13

When brake pedal is

depressed: 0

When brake pedal is

released: 12 — 14

—

Brake switch 2

B135

28

When brake pedal is

depressed: 10 — 13

When brake pedal is

released: 0

When brake pedal is

depressed: 12 — 14

When brake pedal is

released: 0

—

Contents

Connector

No.

Terminal

No.

Signal (V)

Note

Ignition SW ON

(engine OFF)

Engine ON

(idling)

EN(H4DOTC)(diag)-20

Engine Control Module (ECM) I/O Signal

ENGINE (DIAGNOSTICS)

Cruise control command switch

B135

24

When not operating:

3.5 — 4.5

When operating

RES/ACC: 2.5 — 3.5

When operating SET/

COAST: 0.5 — 1.5

When operating

CANCEL 0 — 0.5

When not operating:

3.5 — 4.5

When operating

RES/ACC: 2.5 — 3.5

When operating SET/

COAST: 0.5 — 1.5

When operating

CANCEL: 0 — 0.5

—

Cruise control main switch

B135

12

ON: 0

OFF: 5

ON: 0

OFF: 5

—

Fuel tank pressure sensor

B135

32

2.3 — 2.7

2.3 — 2.7

—

Pressure control solenoid valve

B136

28

ON: 1 or less

OFF: 10 — 13

ON: 1 or less

OFF: 12 — 14

—

Drain valve

B136

17

ON: 1 or less

OFF: 10 — 13

ON: 1 or less

OFF: 12 — 14

—

Fuel temperature sensor

B135

17

2.5 — 3.8

2.5 — 3.8

Ambient temperature:

25°C (77°F)

Immobilizer

Signal 1

B136

26

—

—

—

Signal 2

B136

34

—

—

—

CAN communication (+)

B136

27

—

—

—

CAN communication (–)

B136

35

—

—

—

AT/MT identification

B136

15

0

0

—

Blow-by leak diagnosis signal

B134

30

0

0

At the time of open

circuit (fault): 5

Tumble generator valve position
sensor signal (RH)

B134

26

Fully closed:

0.4 — 1.2

Fully opened:

2.8 — 4.6

Fully closed:

0.4 — 1.2

Fully opened:

2.8 — 4.6

—

Tumble generator valve position
sensor signal (LH)

B134

16

Fully closed:

0.4 — 1.2

Fully opened:

2.8 — 4.6

Fully closed:

0.4 — 1.2

Fully opened:

2.8 — 4.6

—

Tumble generator valve RH
(closed)

B137

23

0 or 10 — 13

0 or 12 — 14

—

Tumble generator valve LH
(closed)

B137

13

0 or 10 — 13

0 or 12 — 14

—

Tumble generator valve RH
(open)

B137

22

0 or 10 — 13

0 or 12 — 14

—

Tumble generator valve LH
(open)

B137

12

0 or 10 — 13

0 or 12 — 14

—

Secondary air
pipe pressure
sensor

Signal

B134

27

2.2 — 2.8

2.2 — 2.8

When secondary air

is inducted: 3.2 — 4.9

Power supply

B134

19

5.12

5.12

—

GND (sensor)

B134

29

0

0

—

Secondary air combination
valve relay 1

B136

30

ON: 0

OFF: 10 — 13

ON: 0

OFF: 12 — 14

—

Secondary air combination
valve relay 2

B136

19

ON: 0

OFF: 10 — 13

ON: 0

OFF: 12 — 14

—

Secondary air pump relay

B136

8

ON: 0

OFF: 10 — 13

ON: 0

OFF: 12 — 14

—

Self-shutoff control

B136

23

10 — 13

12 — 14

—

Ground (ignition system)

B137

26

0

0

—

B137

6

0

0

—

Contents

Connector

No.

Terminal

No.

Signal (V)

Note

Ignition SW ON

(engine OFF)

Engine ON

(idling)