Subaru Legacy IV (2008 year). Manual — part 129

EN(H4SO)(diag)-119

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Q: DTC P0108 MANIFOLD ABSOLUTE PRESSURE/BAROMETRIC PRESSURE

CIRCUIT HIGH INPUT

DTC DETECTING CONDITION:
• Immediately at fault recognition
• GENERAL DESCRIPTION <Ref. to GD(H4SO)-31, DTC P0108 MANIFOLD ABSOLUTE PRESSURE/
BAROMETRIC PRESSURE CIRCUIT HIGH INPUT, Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:
After repair or replacement of faulty parts, perform Clear Memory Mode <Ref. to EN(H4SO)(diag)-50,
OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(H4SO)(diag)-41, PROCEDURE,
Inspection Mode.>.
WIRING DIAGRAM:

EN-04029

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

19

20

7

B21

E2

2

3

1

E21

E21

ECM

B21

B134

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

B134

MANIFOLD

ABSOLUTE
PRESSURE

SENSOR

1 2 3

29

6

19

EN(H4SO)(diag)-120

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step

Check

Yes

No

1

CHECK CURRENT DATA.
1) Start the engine.
2) Read the data of intake manifold absolute
pressure signal using Subaru Select Monitor or
general scan tool.

NOTE:
• SUBARU SELECT MONITOR
For detailed operation procedure, refer to
“READ CURRENT DATA FOR ENGINE”. <Ref.
to EN(H4SO)(diag)-33, Subaru Select Moni-
tor.>
• General Scan Tool
For detailed operation procedures, refer to the
general scan tool operation manual.

Is the measured value 119.5 kPa
(896.5 mmHg, 35.29 inHg) or
more?

Go to step 2.

Even if DTC is
detected, the cir-
cuit has returned to
a normal condition
at this time. Repro-
duce the failure,
and then perform
the diagnosis
again.

NOTE:
In this case, tem-
porary poor con-
tact of connector
may be the cause.

2

CHECK HARNESS BETWEEN ECM AND
MANIFOLD ABSOLUTE PRESSURE SEN-
SOR CONNECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from manifold
absolute pressure sensor.
3) Start the engine.
4) Read the data of intake manifold absolute
pressure signal using Subaru Select Monitor or
general scan tool.

NOTE:
• SUBARU SELECT MONITOR
For detailed operation procedure, refer to
“READ CURRENT DATA FOR ENGINE”. <Ref.
to EN(H4SO)(diag)-33, Subaru Select Moni-
tor.>
• General Scan Tool
For detailed operation procedures, refer to the
general scan tool operation manual.

Is the measured value 119.5 kPa
(896.5 mmHg, 35.29 inHg) or
more?

Repair the short
circuit to power in
harness between
ECM and manifold
absolute pressure
sensor connector.

Go to step 3.

3

CHECK HARNESS BETWEEN ECM AND
MANIFOLD ABSOLUTE PRESSURE SEN-
SOR CONNECTOR.
1) Turn the ignition switch to OFF.
2) Measure the resistance of harness between
manifold absolute pressure sensor connector
and engine ground.

Connector & terminal

(E21) No. 2 — Engine ground:

Is the resistance less than 5

:? Go to step 4.

Repair the harness
and connector.

NOTE:
In this case, repair
the following item:
• Open circuit of
harness between
ECM and manifold
absolute pressure
sensor connector.
• Poor contact in
ECM connector
• Poor contact of
coupling connector

4

CHECK POOR CONTACT.
Check for poor contact in manifold absolute
pressure sensor connector.

Is there poor contact in mani-
fold absolute pressure sensor
connector?

Repair the poor
contact of mani-
fold absolute pres-
sure sensor
connector.

Replace the mani-
fold absolute pres-
sure sensor. <Ref.
to FU(H4SO)-27,
Manifold Absolute
Pressure Sensor.>

EN(H4SO)(diag)-121

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

R: DTC P0111 INTAKE AIR TEMPERATURE SENSOR 1 CIRCUIT RANGE/

PERFORMANCE

DTC DETECTING CONDITION:
• Two consecutive driving cycles with fault
• GENERAL DESCRIPTION <Ref. to GD(H4SO)-32, DTC P0111 INTAKE AIR TEMPERATURE SENSOR
1 CIRCUIT RANGE/PERFORMANCE, Diagnostic Trouble Code (DTC) Detecting Criteria.>
TROUBLE SYMPTOM:
• Improper idling
• Poor driving performance

CAUTION:
After repair or replacement of faulty parts, perform Clear Memory Mode <Ref. to EN(H4SO)(diag)-50,
OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(H4SO)(diag)-41, PROCEDURE,
Inspection Mode.>.
WIRING DIAGRAM:

EN-06837

E

B83

3

B3

ECM

B135

SBF-7

*

*

4

1

5

2

34

18

26

30

35

B47

1

2

4

6

3

5

BATTERY

MASS AIR FLOW

& INTAKE AIR

TEMPERATURE

SENSOR

MAIN RELAY

: TERMINAL No. OPTIONAL

ARRANGEMENT

*

B3

1 2 3 4 5

3

4

1

2

5

6

B47

1 2 3 4
5 6 7 8

B83

B135

5

6

7

2

1

3

4

29

10 11 12 13 14 15

25

24

16

30

9

8

17 18 19

20
28

21 22 23

32

31

26 27

33

34 35

EN(H4SO)(diag)-122

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step

Check

Yes

No

1

CHECK ENGINE COOLANT TEMPERA-
TURE.
1) Start the engine and warm up completely.
2) Measure the engine coolant temperature
using the Subaru Select Monitor or general
scan tool.

NOTE:
• SUBARU SELECT MONITOR
For detailed operation procedure, refer to
“READ CURRENT DATA FOR ENGINE”. <Ref.
to EN(H4SO)(diag)-33, Subaru Select Moni-
tor.>
• General Scan Tool
For detailed operation procedures, refer to the
general scan tool operation manual.

Is the engine coolant tempera-
ture 75°C (167°F) or higher?

Replace the mass
air flow and intake
air temperature
sensor. <Ref. to
FU(H4SO)-28,
Mass Air Flow and
Intake Air Temper-
ature Sensor.>

Check DTC P0125
using “List of Diag-
nostic Trouble
Code (DTC)”.
<Ref. to
EN(H4SO)(diag)-
80, List of Diagnos-
tic Trouble Code
(DTC).>