Subaru Legacy III (2000-2003 year). Manual - part 516

EN(H4DOSTC)-234

ENGINE (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

BK:DTC P1518 — STARTER SWITCH CIRCUIT LOW INPUT —

• TROUBLE SYMPTOM:

• Failure of engine to start

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-00930

BATTERY

IGNITION

SWITCH

STARTER
MOTOR

SBF-4

SBF-1

B72

B72

B14

B134 ECM

E

E

1

3

16

3 4

1 2

B134

B12

T7

1 2 3 4

10 11 12

19 20 21

13

5

6

14 15

7

8 9

16 17

18

22

12

INHIBITOR SWITCH

7

P

R

N

D

3

2

1

12

11

T7

T3

B12

AT

AT

MT

MT

1 2 3 4 5 6
7 8 9 10 11 12

1 2 3 4
5 6 7 8
9 10 11 12

EN(H4DOSTC)-235

ENGINE (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

Step

Value

Yes

No

1

CHECK OPERATION OF STARTER MOTOR.
Does the starter motor operate when ignition 
switch to “ST”?

Operates.

Repair the har-
ness and connec-
tor.

NOTE:
In this case, repair
the following:
• Open or ground 
short circuit in har-
ness between 
ECM and starter 
motor connector.
• Poor contact in 
ECM connector.

Check the starter 
motor circuit. <Ref. 
to EN(H4DOSTC)-
52, STARTER 
MOTOR CIR-
CUIT, Diagnostics 
for Engine Start-
ing Failure.>

EN(H4DOSTC)-236

ENGINE (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

BL:DTC P1560 — BACK-UP VOLTAGE CIRCUIT MALFUNCTION —

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-00931

B72

B137

3 4

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

BATTERY

IGNITION
SWITCH

MAIN  RELAY

SBF-4

SBF-1

SBF-5

B72

TO FRONT OXYGEN(A/F) SENSOR

A2

D8

D9

A22

C17

C8

C18

A7

A15

E1

A12

D2

D3

D10

A14

No.11

B47

E3

B22

1

2

3

5

6

4

ECM

E

E

1

4

B134

B136

B137

A :

C :

D :

B84

E :

3

15

16

14

13

E

3

4

1

2

5

6

1 2 3 4
5 6 7 8
9 10 11 12

13 14 15 16

B134

B22

B47

B84

B136

1 2 3 4

10 11 12

19 20 21

13

5

6

14 15

7

8 9

16 17

18

22

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

8 9 10

4

11 12

13 14 15

16

5 6

7

17

EN(H4DOSTC)-237

ENGINE (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

Step

Value

Yes

No

1

CHECK INPUT SIGNAL FOR ECM.
1) Turn the ignition switch to OFF.
2) Measure the voltage between ECM and 

chassis ground.

Connector & terminal

(B137) No. 10 (+) — Chassis ground (

−−−−

):

Does the measured value exceed the spec-
ified value?

10 V

Repair the poor 
contact in 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 of harness 

between ECM and chassis ground.

Connector & terminal

(B137) No. 10 — Chassis ground:

Does the measured value exceed the spec-
ified value?

1 M

Ω

Go to step 3.

Repair the ground 
short circuit in har-
ness between 
ECM connector 
and battery termi-
nal.

3

CHECK FUSE SBF-5.
Is the fuse blown?

Fuse is blown-out.

Replace the fuse.

Repair the har-
ness and connec-
tor.

NOTE:
In this case, repair
the following:

• Open circuit in 
harness between 
ECM and battery
• Poor contact in 
ECM connector
• Poor contact in 
battery terminal