Subaru Legacy (2005 year). Manual - part 192

EN(H4SO 2.5)(diag)-53

ENGINE (DIAGNOSTICS)

Diagnostics for Engine Starting Failure

16.Diagnostics for Engine Starting Failure

A: PROCEDURE

1. Check for fuel amount.

↓

2. Inspection of starter motor circuit. <Ref. to EN(H4SO 2.5)(diag)-54, STARTER MOTOR CIRCUIT, Diagnostics for Engine Start-
ing Failure.>

↓

3. Inspection of ECM power supply and ground line. <Ref. to EN(H4SO 2.5)(diag)-57, CHECK POWER SUPPLY AND GROUND 
LINE OF ENGINE CONTROL MODULE (ECM), Diagnostics for Engine Starting Failure.>

↓

4. Inspection of ignition control system. <Ref. to EN(H4SO 2.5)(diag)-60, IGNITION CONTROL SYSTEM, Diagnostics for Engine 
Starting Failure.>

↓

5. Inspection of fuel pump circuit. <Ref. to EN(H4SO 2.5)(diag)-63, FUEL PUMP CIRCUIT, Diagnostics for Engine Starting Fail-
ure.>

↓

6. Inspection of fuel injector circuit. <Ref. to EN(H4SO 2.5)(diag)-66, FUEL INJECTOR CIRCUIT, Diagnostics for Engine Starting 
Failure.>

EN(H4SO 2.5)(diag)-54

ENGINE (DIAGNOSTICS)

Diagnostics for Engine Starting Failure

B: STARTER MOTOR CIRCUIT

CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode <Ref. to EN(H4SO 2.5)(diag)-
40, Clear Memory Mode.> and Inspection Mode <Ref. to EN(H4SO 2.5)(diag)-33, Inspection Mode.>.
WIRING DIAGRAM:
• EC, EK, EH, ER and K4 model

EN-03453

D8

B32

No.21

B225

MAIN SBF

SBF-6

E

ECM

B137

D:

B135

B:

B72

B14

M

2

3

B225

B137

B72

D:

B135

B:

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 36

39 40

37
38

1

2

9

3

4

5

6

7

8

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

29 30 31

13 14 15 16 17

27

28

18

22 23

24 25

26

32 33

34 35

1

3

4 5 6

2

BATTERY

IGNITION
SWITCH

STARTER
RELAY

STARTER MOTOR

LHD

LHD

RHD

RHD

16

14

15

13

15

13

16

14

EN(H4SO 2.5)(diag)-55

ENGINE (DIAGNOSTICS)

Diagnostics for Engine Starting Failure

• KA and KS model

NOTE:
Fuel injection system for KA and KS model is the same as 2.0 L model. Refer to EN(H4SO 2.0) section.

Step

Check

Yes

No

1

CHECK OPTION CODE.

Is the option code EC, EK, EH, 
ER or K4?

Go to step 2.

Refer to EN(H4SO 
2.0) section. <Ref. 
to EN(H4SO 
2.0)(diag)-64, List 
of Diagnostic Trou-
ble Code (DTC).>

NOTE:
Fuel injection sys-
tem for KA and KS
model is the same
as 2.0 L model.

2

CHECK BATTERY.
Check the battery voltage.

Is the voltage more than 12 V? Go to step 3.

Charge or replace 
the battery.

3

CHECK OPERATION OF STARTER MOTOR. Does the starter motor oper-

ate?

Go to step 4.

Go to step 5.

4

CHECK DTC.

Is DTC displayed? <Ref. to 
EN(H4SO 2.5)(diag)-32, 
OPERATION, Read Diagnos-
tic Trouble Code (DTC).>

Inspect the rele-
vant DTC using 
List of Diagnostic 
Trouble Code 
(DTC). <Ref. to 
EN(H4SO 
2.5)(diag)-69, List 
of Diagnostic Trou-
ble Code (DTC).>

Repair the poor 
contact in ECM 
connector.

5

CHECK INPUT SIGNAL OF STARTER MO-
TOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from starter 
motor.
3) Turn the ignition switch to START.
4) Measure the power supply voltage between 
starter motor connector terminal and engine 
ground.

Connector & terminal

(B14) No. 1 (+) — Engine ground (

−

):

NOTE:

• For AT model, place the select lever in “P” or 
“N” range.
• For MT model, depress the clutch pedal.

Is the voltage more than 10 V? Check the starter 

motor. <Ref. to 
SC(H4SO 2.0)-6, 
Starter.>

Go to step 6.

6

CHECK HARNESS BETWEEN BATTERY 
AND IGNITION SWITCH CONNECTOR.
1) Disconnect the connector from ignition 
switch.
2) Measure the power supply voltage between 
ignition switch connector and chassis ground.

Connector & terminal

(B72) No. 3 (+) — Chassis ground (

−

):

Is the voltage more than 10 V? Go to step 7.

Repair the open 
circuit of harness 
between ignition 
switch and bat-
tery, and check 
fuse SBF No. 6 
and MAIN SBF.

7

CHECK IGNITION SWITCH.
1) Disconnect the connector from ignition 
switch.
2) Measure the resistance between ignition 
switch terminals after turning the ignition 
switch to START position.

Terminals

No. 2 — No. 3:

Is the resistance less than 5 
Ω?

Go to step 8.

Replace the igni-
tion switch.

EN(H4SO 2.5)(diag)-56

ENGINE (DIAGNOSTICS)

Diagnostics for Engine Starting Failure

8

CHECK INPUT VOLTAGE OF STARTER RE-
LAY.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from starter relay.
3) Connect the connector to ignition switch.
4) Measure the input voltage between starter 
relay connector and chassis ground after turn-
ing the ignition switch to START position.

Connector & terminal
LHD model

(B225) No. 13 (+) — Chassis ground (

−

):

(B225) No. 15 (+) — Chassis ground (

−

):

RHD model

(B225) No. 14 (+) — Chassis ground (

−

):

(B225) No. 16 (+) — Chassis ground (

−

):

Is the voltage more than 10 V? Go to step 9.

Repair the open 
circuit of harness 
between starter 
relay and ignition 
switch.

9

CHECK STARTER RELAY.
1) Connect the battery to starter relay termi-
nals No. 15 and No. 16.
2) Measure the resistance between starter 
relay terminals.

Terminals

No. 13 — No. 14:

Is the resistance less than 1 
Ω?

Go to step 10.

Replace the 
starter relay.

10

CHECK INPUT VOLTAGE OF ECM.
1) Turn the ignition switch to OFF.
2) Connect the connector to starter relay.
3) Disconnect the connector from ECM.
4) Turn the ignition switch to START.
5) Measure the voltage between ECM and 
chassis ground.

Connector & terminal

(B135) No. 32 (+) — Chassis ground (

−

):

(B137) No. 8 (+) — Chassis ground (

−

):

Is the voltage more than 10 V? Replace the ECM. 

<Ref. to FU(H4SO 
2.5)-37, Engine 
Control Module 
(ECM).>

Repair the open or 
ground short cir-
cuit of harness 
between ECM and 
starter relay.

Step

Check

Yes

No