Subaru Impreza 3 / Impreza WRX / Impreza WRX STI. Manual — part 266

EN(H4DOTC)(diag)-288

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

30

CHECK HARNESS BETWEEN ECM AND
ELECTRONIC THROTTLE CONTROL CON-
NECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from ECM.
3) Measure the resistance between ECM con-
nectors.

Connector & terminal

(B134) No. 19 — (B134) No. 18:
(B134) No. 19 — (B134) No. 28:

Is the resistance 1 MΩ or
more?

Go to step

31.

Repair the short
circuit to power in
the harness
between ECM con-
nector and elec-
tronic throttle
control connector.

31

CHECK SENSOR OUTPUT.
1) Connect all connectors.
2) Turn the ignition switch to ON.
3) Read the value of «Main-Throttle Sensor»
using Subaru Select Monitor.
NOTE:

For detailed operation procedures, refer to
“READ CURRENT DATA FOR ENGINE”. <Ref.
to EN(H4DOTC)(diag)-40, Subaru Select Moni-
tor.>

Is the value of «Main-Throttle
Sensor» 0.81 — 0.87 V?

Go to step

32.

Repair the poor
contact of elec-
tronic throttle con-
trol connector.
Replace the elec-
tronic throttle con-
trol if defective.
<Ref. to FU(STI)-
15, Throttle Body.>
<Ref. to FU(w/o
STI)-15, Throttle
Body.>

32

CHECK SENSOR OUTPUT.
Read the value of «Sub-Throttle Sensor» using
Subaru Select Monitor.
NOTE:

For detailed operation procedures, refer to
“READ CURRENT DATA FOR ENGINE”. <Ref.
to EN(H4DOTC)(diag)-40, Subaru Select Moni-
tor.>

Is the value of «Sub-Throttle
Sensor» 1.64 — 1.70 V?

Go to step

33.

Repair the poor
contact of elec-
tronic throttle con-
trol connector.
Replace the elec-
tronic throttle con-
trol if defective.
<Ref. to FU(STI)-
15, Throttle Body.>
<Ref. to FU(w/o
STI)-15, Throttle
Body.>

33

CHECK HARNESS BETWEEN ECM AND
ELECTRONIC THROTTLE CONTROL MO-
TOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connectors from ECM and
electronic throttle control.
3) Measure the resistance between ECM con-
nector and electronic throttle control connector.

Connector & terminal

(B134) No. 2 — (E57) No. 2:
(B134) No. 1 — (E57) No. 1:

Is the resistance less than 1 Ω? Go to step

34.

Repair the harness
and connector.
NOTE:

In this case, repair
the following item:
• Open circuit in
harness between
ECM

connector

and

electronic

throttle

control

connector
• Poor contact of
coupling connector

34

CHECK HARNESS BETWEEN ECM AND
ELECTRONIC THROTTLE CONTROL MO-
TOR.
1) Connect the connector to ECM.
2) Turn the ignition switch to ON.
3) Measure the voltage between electronic
throttle control connector and engine ground.

Connector & terminal

(E57) No. 2 (+) — Engine ground (–):
(E57) No. 1 (+) — Engine ground (–):

Is the voltage 5 V or more?

Repair the short
circuit to power in
the harness
between ECM con-
nector and elec-
tronic throttle
control connector.

Go to step

35.

Step

Check

Yes

No

EN(H4DOTC)(diag)-289

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

CY:DTC P050B COLD START IGNITION TIMING PERFORMANCE

NOTE:

For the diagnostic procedure, refer to DTC P050A. <Ref. to EN(H4DOTC)(diag)-280, DTC P050A COLD

START IDLE AIR CONTROL SYSTEM PERFORMANCE, Diagnostic Procedure with Diagnostic Trouble

Code (DTC).>

35

CHECK HARNESS BETWEEN ECM AND
ELECTRONIC THROTTLE CONTROL MO-
TOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from ECM.
3) Measure the resistance between electronic
throttle control connector and engine ground.

Connector & terminal

(E57) No. 2 — Engine ground:
(E57) No. 1 — Engine ground:

Is the resistance 1 MΩ or
more?

Go to step

36.

Repair the ground
short circuit of har-
ness between
ECM connector
and electronic
throttle control
connector.

36

CHECK ELECTRONIC THROTTLE CON-
TROL MOTOR HARNESS.
Measure the resistance between electronic
throttle control connectors.

Connector & terminal

(E57) No. 2 — (E57) No. 1:

Is the resistance 1 MΩ or
more?

Go to step

37.

Repair the short
circuit in harness
between ECM con-
nector and elec-
tronic throttle
control connector.

37

CHECK ELECTRONIC THROTTLE CON-
TROL GROUND CIRCUIT.
Measure the resistance between ECM connec-
tor and chassis ground.

Connector & terminal

(B134) No. 3 — Chassis ground:
(B134) No. 4 — Chassis ground:
(B134) No. 6 — Chassis ground:
(B137) No. 1 — Chassis ground:
(B137) No. 3 — Chassis ground:

Is the resistance less than 5 Ω? Go to step

38.

Repair the harness
and connector.
NOTE:

In this case, repair
the following item:
• Open circuit of
harness between
ECM

connector

and engine ground
• Poor contact of
coupling connector

38

CHECK ELECTRONIC THROTTLE CON-
TROL.
Measure the resistance between electronic
throttle control terminals.

Terminals

No. 1 — No. 2:

Is the resistance 50 Ω or less? Go to step

39.

Replace the elec-
tronic throttle con-
trol. <Ref. to
FU(STI)-15, Throt-
tle Body.> <Ref. to
FU(w/o STI)-15,
Throttle Body.>

39

CHECK ELECTRONIC THROTTLE CON-
TROL.
Move the throttle valve to the fully open and fully
closed positions with fingers.
Check that the valve returns to the specified
position when releasing fingers.

Does the valve return to the
specified position? Standard
value: 3 mm (0.12 in) from fully
closed position

Repair the poor
contact of ECM
connector.

Replace the elec-
tronic throttle con-
trol. <Ref. to
FU(STI)-15, Throt-
tle Body.> <Ref. to
FU(w/o STI)-15,
Throttle Body.>

Step

Check

Yes

No

EN(H4DOTC)(diag)-290

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

CZ:DTC P0560 SYSTEM VOLTAGE

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(H4DOTC)-190, DTC P0560 SYSTEM VOLTAGE, Diagnostic

Trouble Code (DTC) Detecting Criteria.>
CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(H4DOTC)(diag)-63,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(H4DOTC)(diag)-49, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine electrical system, without SI-DRIVE <Ref. to WI-32, WITHOUT SI-DRIVE, WIRING DIAGRAM,

Engine Electrical System.>

• Engine electrical system, with SI-DRIVE <Ref. to WI-48, WITH SI-DRIVE, WIRING DIAGRAM, Engine

Electrical System.>

ECM

EN-08715

B136

C:

B72

C1

D7

B13

A3

A6

C2 C30

24

23

22

21

B134

B135

A:

C: B136

D: B137

B:

35

34

40

A4

D3

36

B134

B135

B137

B21

B72

A:

B:

D:

D1

3

1

15A

B220

B220

B220

3

4

18

19

6

7

4

3
5

2

1

12

11

10

9

8

40

36 39

38

37

34

33

35

32

28 31

30

29

23

22

21

20

26

25

24

27

17

16

15

14

13

2

6

5

4

3

1

54

52 53

50 51

48 49

46 47

45

44

42 43

40 41

38 39

36 37

34 35

33

32

31

30

29

28

27

26

25

24

23

22

21

20

11

10

9

19

18

17

16

8

7

6

5

15

14

13

12

4

3

2

1

31

30

29

28

27

21

20

19

18

17

16

26

25

24

15

14

13

12

11

23

22

10

3

4

9

1

2

8

7

6

5

35

34

33

32

31

30

29

21

20

19

18

17

16

28

27

26

15

14

13

12

11

25

23

22

24

10

3

4

9

1

2

8

7

6

5

31

30

32

29

34

33

21

20

19

18

17

16

28

27

26

15

14

13

12

11

25

23

22

24

10

3

4

9

1

2

8

7

6

5

B21

E2

35

27

16

10 11 12 13 14 15

25

24

30

9

8

7

17 18 19 20
28

21 22 23

29

32

31

1

2

3

4

5

6

26

33 34

E

E

SBF-7

SBF-6

FUSE

(RELAY BLOCK)

IGNITION

SWITCH

BATTERY

MAIN RELAY

No. 13

No. 12

MAIN SBF

EN(H4DOTC)(diag)-291

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step

Check

Yes

No

1

CHECK INPUT SIGNAL OF ECM.
1) Turn the ignition switch to OFF.
2) Measure the voltage between ECM connec-
tor and chassis ground.

Connector & terminal

(B136) No. 2 (+) — Chassis ground (–):

Is the voltage 10 V or more?

Repair the poor
contact of ECM
connector.

Go to step

2.

2

CHECK HARNESS BETWEEN ECM AND
MAIN FUSE BOX CONNECTOR.
1) Disconnect the connector from ECM.
2) Measure the resistance between ECM con-
nector and chassis ground.

Connector & terminal

(B136) No. 2 — Chassis ground:

Is the resistance 1 MΩ or
more?

Go to step

3.

Repair the short
circuit to ground in
harness between
ECM connector
and battery termi-
nal.

3

CHECK FUSE NO. 13.

Is the fuse blown out?

Replace the fuse. Repair the harness

and connector.
NOTE:

In this case, repair
the following item:
• Open circuit in
harness between
ECM

connector

and battery
• Poor contact of
ECM connector
• Poor contact of
battery terminal