Subaru Legacy IV (2008 year). Manual - part 323

EN(H4DOTC)(diag)-113

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

O: DTC P0108 MANIFOLD ABSOLUTE PRESSURE/BAROMETRIC PRESSURE 

CIRCUIT HIGH INPUT

DTC DETECTING CONDITION:
• Immediately at fault recognition
• GENERAL DESCRIPTION <Ref. to GD(H4DOTC)-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(H4DOTC)(diag)-
52, OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(H4DOTC)(diag)-43, PRO-
CEDURE, Inspection Mode.>.
WIRING DIAGRAM:

EN-05671

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

23

28

6

B21

E2

2

3

1

E21

E21

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

1 2 3

6

29

19

MANIFOLD

ABSOLUTE
PRESSURE

SENSOR

ECM

EN(H4DOTC)(diag)-114

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(H4DOTC)(diag)-34, 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(H4DOTC)(diag)-34, 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. 1 — 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(H4DOTC)-
37, Manifold Abso-
lute Pressure Sen-
sor.>

EN(H4DOTC)(diag)-115

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

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

PERFORMANCE

DTC DETECTING CONDITION:
• Two consecutive driving cycles with fault
• GENERAL DESCRIPTION <Ref. to GD(H4DOTC)-32, DTC P0111 INTAKE AIR TEMPERATURE SEN-
SOR 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(H4DOTC)(diag)-
52, OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(H4DOTC)(diag)-43, PRO-
CEDURE, Inspection Mode.>.
WIRING DIAGRAM:

EN-05087

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

B3

E

B83

1

B3

ECM

B135

SBF-7

1 2 3 4 5

3

4

1

2

5

6

B47

*

*

2

4

3

5

34

18

26

30

35

B47

1

2

4

6

3

5

1 2 3 4
5 6 7 8

B83

BATTERY

MASS AIR FLOW & 

INTAKE AIR 

TEMPERATURE

SENSOR

MAIN RELAY

 : TERMINAL No. OPTIONAL 
   ARRANGEMENT

*

EN(H4DOTC)(diag)-116

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(H4DOTC)(diag)-34, 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(H4DOTC)-36, 
Mass Air Flow and 
Intake Air Temper-
ature Sensor.>

Check DTC P0125 
using “List of Diag-
nostic Trouble 
Code (DTC)”. 
<Ref. to 
EN(H4DOTC)(diag)
-81, List of Diag-
nostic Trouble 
Code (DTC).>