Subaru Legacy III (2000-2003 year). Manual - part 144

EN(H4SO)-188

ENGINE (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

6

CHECK CAMSHAFT POSITION SENSOR.
1) Remove camshaft position sensor.
2) Measure resistance between connector ter-

minals of camshaft position sensor.

Terminals

No. 1 — No. 2:

Is the measured value within the specified 
range?

1 - 4 k

Ω

Go to step 7.

Replace camshaft 
position sensor.  
<Ref. to 
FU(H4SO)-28, 
Camshaft Position 
Sensor.>

7

CHECK CONDITION OF CAMSHAFT POSI-
TION SENSOR.
Turn ignition switch to OFF.
Is the camshaft position sensor installation bolt 
tightened securely?

Tightened securely.

Go to step 8.

Tighten camshaft 
position sensor 
installation bolt 
securely.

8

CHECK CAMSHAFT SPROCKET.
Remove front belt cover. 
Are camshaft sprocket teeth cracked or dam-
aged?

Cracked or damaged.

Replace camshaft 
sprocket.  <Ref. to 
ME (H4SO)-, 
Camshaft 
Sprocket.>

Go to step 9.

9

CHECK INSTALLATION CONDITION OF 
TIMING BELT.
Turn camshaft using ST, and align alignment 
mark on camshaft sprocket with alignment 
mark on timing belt cover LH.
Is timing belt dislocated from its proper posi-
tion?

Dislocated from proper posi-
tion.

Repair installation 
condition of timing 
belt. <Ref. to 
ME(H4SO)-46, 
Timing Belt 
Assembly.>

Replace camshaft 
position sensor.  
<Ref. to 
FU(H4SO)-27, 
Crankshaft Posi-
tion Sensor.>

Step

Value

Yes

No

EN(H4SO)-189

ENGINE (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

MEMO:

EN(H4SO)-190

ENGINE (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

AM:DTC P0400 — EXHAUST GAS RECIRCULATION FLOW —

• DTC DETECTING CONDITION:

• Two consecutive driving cycles with fault

• TROUBLE SYMPTOM:

• Poor driving performance on low engine speed
• Erroneous idling
• Poor driving performance.

CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode<Ref. to EN(H4SO)-47, OPER-
ATION, Clear Memory Mode.> and Inspection Mode <Ref. to EN(H4SO)-40, OPERATION, Inspection 
Mode.> .
• WIRING DIAGRAM:

EN-01129

F44

B61

6

RHD

RHD

BATTERY

SBF-5

B47

MAIN RELAY

1

2

3

5

4

6

F44

1 2 3 4
5 6 7 8

1

6

3

4

1

B22

E3

E58

B328

EGR

SOLENOID 

VALVE

2

5

E18

5

6

4

3

ECM

18

17

16

15

B134

B22

1 2 3 4
5 6 7 8
9 10 11 12

13 14 15 16

B47

3

4

5

6

1

2

LHD

LHD

E18

B328

1

3

4 5 6

2

B134

1 2

3 4

5 6

7 8

9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

24 25

26 27 28 29

30 31 32 33

34 35

EN(H4SO)-191

ENGINE (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

Step

Value

Yes

No

1

CHECK ANY OTHER DTC ON DISPLAY.
Is any other DTC displayed?

Other DTC indicated on dis-
play.

Inspect the rele-
vant DTC using 
“List of Diagnostic 
Trouble Code 
(DTC)”. <Ref. to 
EN(H4SO)-83, List 
of Diagnostic 
Trouble Code 
(DTC).>

Go to step 2.

2

CHECK CURRENT DATA.
1) Start engine.
2) Rear the data of intake manifold absolute 

pressure signal using Subaru Select Moni-
tor or OBD-II general scan tool.
Does the measured value exceed the spec-
ified value?

NOTE:

•Subaru Select Monitor
For detailed operation procedure, refer to the 
“READ CURRENT DATA FOR ENGINE”.  
<Ref. to EN(H6DO)-34, Subaru Select Moni-
tor.>
•OBD-II general scan tool
For detailed operation procedures, refer to the 
OBD-II General Scan Tool Instruction Manual.

53.3 kPa (400 mmHg, 15.75 
inHg)

Check if EGR 
valve, intake mani-
fold pressure sen-
sor and throttle 
body are securely 
installed.

Go to step 3.

3

CHECK POWER SUPPLY TO EGR SOLE-
NOID VALVE.
1) Disconnect connector from EGR solenoid 

valve.

2) Turn ignition switch to ON.
3) Measure voltage between EGR solenoid 

valve and engine ground.

Connector & terminal

(E18) No. 2 — Engine ground:
(E18) No. 5 — Engine ground:

Does the measured value exceed the 
specified value?

10 V

Go to step 4.

Repair open circuit 
in harness 
between main 
relay and EGR 
solenoid valve 
connector.

4

CHECK EGR SOLENOID VALVE.
Measure resistance between EGR solenoid 
valve terminals.

NOTE:

Make sure there are no foreign objects caught
between EGR solenoid valve and valve seat.

Terminals

No. 1 — No. 2:
No. 3 — No. 2:
No. 4 — No. 5:
No. 6 — No. 5:

Is the measured value within the specified 
range?

20 — 30 

Ω

Go to step 5.

Replace EGR 
solenoid valve.  
<Ref. to 
FU(H4SO)-35, 
EGR Valve.>