Subaru Legacy III (2000-2003 year). Manual - part 490

EN(H4DOSTC)-130

ENGINE (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

V: DTC P0261 — CYLINDER 1 INJECTOR CIRCUIT LOW —

NOTE:
For the diagnostic procedure, refer to DTC P0270. <Ref. to EN(H4DOSTC)-132, DTC P0270 — CYLINDER
4 INJECTOR CIRCUIT LOW —, Diagnostic Procedure with Diagnostic Trouble Code (DTC).>

W: DTC P0264 — CYLINDER 2 INJECTOR CIRCUIT LOW —

NOTE:
For the diagnostic procedure, refer to DTC P0270. <Ref. to EN(H4DOSTC)-132, DTC P0270 — CYLINDER
4 INJECTOR CIRCUIT LOW —, Diagnostic Procedure with Diagnostic Trouble Code (DTC).>

X: DTC P0267 — CYLINDER 3 INJECTOR CIRCUIT LOW —

NOTE:
For the diagnostic procedure, refer to DTC P0270. <Ref. to EN(H4DOSTC)-132, DTC P0270 — CYLINDER
4 INJECTOR CIRCUIT LOW —, Diagnostic Procedure with Diagnostic Trouble Code (DTC).>

EN(H4DOSTC)-131

ENGINE (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

MEMO:

EN(H4DOSTC)-132

ENGINE (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

Y: DTC P0270 — CYLINDER 4 INJECTOR CIRCUIT LOW —

• TROUBLE SYMPTOM:

• Engine stalls.
• Erroneous idling
• Rough driving

CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode <Ref. to EN(H4DOSTC)-35, 
OPERATION, Clear Memory Mode.> and Inspection Mode <Ref. to EN(H4DOSTC)-33, Inspection 
Mode.> .
• WIRING DIAGRAM:

EN-00940

BATTERY

FUEL INJECTORS

MAIN RELAY

E

#4

1

2

SBF-5

#3

1

2

#2

1

2

#1

1

2

1

9

10

11

12

1 2

1

2

7

8

9

5

6

3

4

10 11 12

19 20 21
29 30 31

13 14 15 16 17

27 28

18

22 23 24 25 26

1 2

7

8 9

5

6

3

4

10 11 12
19 20 21

13 14 15 16

17 18

22 23 24

1 2 3 4
5 6 7 8
9 10 11 12

13 14 15 16

6
4

5
3

2
1

B22

B22

B136

B137

E5

E5

E3

E6

E6

E16

E16

E17

B47

E17

C :

D :

D1

C6

C5

C4

B136

B137

ECM

B47

3

4

1

2

5

6

EN(H4DOSTC)-133

ENGINE (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

Step

Value

Yes

No

1

CHECK OPERATION OF EACH FUEL INJEC-
TOR.
While cranking the engine, check that each 
fuel injector emits “operating” sound. Use a 
sound scope or attach a screwdriver to injector 
for this check.
Does the fuel injector operate?

Operates.

Check the fuel 
pressure.  <Ref. to 
ME(H4DOSTC)-
26, FUEL PRES-
SURE, .>

Go to step 2.

2

CHECK POWER SUPPLY TO EACH FUEL 
INJECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from #1 cylinder 

fuel injector.

3) Turn the ignition switch to ON.
4) Measure the power supply voltage between 

the fuel injector terminal and engine 
ground.

Connector & terminal

#1 (E5) No. 2 (+) — Engine ground (–):
#2 (E16) No. 2 (+) — Engine ground (

−−−−

):

#3 (E6) No. 2 (+) — Engine ground (–):
#4 (E17) No. 2 (+) — Engine ground (–):

Does the measured value exceed the spec-
ified value?

10 V

Go to step 3.

Repair the har-
ness and connec-
tor.

NOTE:
In this case, repair
the following:
• Open circuit in 
harness between 
main relay and fuel 
injector connector
• Poor contact in 
main relay con-
nector
• Poor contact in 
coupling connector
• Poor contact in 
fuel injector con-
nector

3

CHECK HARNESS BETWEEN ECM AND 
FUEL INJECTOR CONNECTOR.
1) Disconnect the connector from ECM.
2) Measure the resistance of harness 

between ECM and fuel injector connector.

Connector & terminal

(B137) No. 1 — (E5) No. 1:
(B136) No. 6 — (E16) No. 1:
(B136) No. 5 — (E6) No. 1:
(B136) No. 4 — (E6) No. 1:

Is the measured value less than the speci-
fied value?

1 

Ω

Go to step 4.

Repair the har-
ness and connec-
tor.

NOTE:
In this case, repair
the following:
• Open circuit in 
the harness 
between ECM and 
fuel injector con-
nector
• Poor contact in 
the coupling con-
nector

4

CHECK HARNESS BETWEEN ECM AND 
FUEL INJECTOR CONNECTOR.
Measure the resistance of harness between 
ECM and fuel injector connector.

Connector & terminal

(B137) No. 1 — Chassis ground:
(B136) No. 6 — Chassis ground:
(B136) No. 5 — Chassis ground:
(B136) No. 4 — Chassis ground:

Does the measured value exceed the specified 
value?

1 M

Ω

Go to step 5.

Repair the ground 
short circuit in har-
ness between 
ECM and fuel 
injector connector.

5

CHECK EACH FUEL INJECTOR.
1) Turn the ignition switch to OFF.
2) Measure the resistance between each fuel 

injector terminals.

Terminals

No. 1 — No. 2:

Is the measured value within the specified 
value?

5 — 20 

Ω

Go to step 6.

Replace the faulty 
fuel injector.