Subaru Legacy III (2000-2003 year). Manual - part 216

EN(H4SOw/oOBD)-54

ENGINE (DIAGNOSTICS)

DIAGNOSTICS FOR ENGINE STARTING FAILURE

2

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

injector.

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

fuel injector terminal and engine ground.

Connector & terminal

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

Does the measured value exceed the spec-
ified value?

10 V

Go to step 3.

Repair harness 
and connector.

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 
(B22)
• Poor contact in 
fuel injector con-
nector

3

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

injector.

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

fuel injector terminal and engine ground.

Connector & terminal

#2 (E16) No. 2 (+) — Engine ground (

−−−−

):

Does the measured value exceed the spec-
ified value?

10 V

Go to step 4.

Repair harness 
and connector.

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 
(B22)
• Poor contact in 
fuel injector con-
nector

4

CHECK POWER SUPPLY TO EACH FUEL 
INJECTOR.
1) Turn ignition switch to OFF.
2) Disconnect connector from #3 cylinder fuel 

injector.

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

fuel injector terminal and engine ground.

Connector & terminal

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

Does the measured value exceed the spec-
ified value?

10 V

Go to step 5.

Repair harness 
and connector.

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 connec-
tors (B22)
• Poor contact in 
fuel injector con-
nector

Step

Value

Yes

No

EN(H4SOw/oOBD)-55

ENGINE (DIAGNOSTICS)

DIAGNOSTICS FOR ENGINE STARTING FAILURE

5

CHECK POWER SUPPLY TO EACH FUEL 
INJECTOR.
1) Turn ignition switch to OFF.
2) Disconnect connector from #4 cylinder fuel 

injector.

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

fuel injector terminal and engine ground.

Connector & terminal

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

Does the measured value exceed the spec-
ified value?

10 V

Go to step 6.

Repair harness 
and connector.

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 connec-
tors (B22)
• Poor contact in 
fuel injector con-
nector

6

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

injector terminals.

Terminals

No. 1 — No. 2:

Is the measured value within the specified 
value?

11 — 12 

Ω

Go to step 7.

Replace faulty fuel 
injector.

7

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

ECM and fuel injector connector.

Connector & terminal

(B134) No. 4 — (B136) No. 2:

Is the measured value within the specified 
value?

11 — 12 

Ω

Go to step 8.

Repair harness 
and connector.

NOTE:
In this case, repair
the following:
• Open circuit in 
harness between 
ECM and fuel 
injector connector
• Poor contact in 
coupling connector 
(B22)

8

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

Connector & terminal

(B134) No. 4 — Chassis ground:

Is the measured value less than the specified 
value?

1 

Ω

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

Go to step 9.

9

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

Connector & terminal

(B134) No. 13 — (B136) No. 2:

Is the measured value within the specified 
value?

11 — 12 

Ω

Go to step 10.

Repair harness 
and connector.

NOTE:
In this case, repair
the following:
• Open circuit in 
harness between 
ECM and fuel 
injector connector
• Poor contact in 
coupling connector 
(B22)

Step

Value

Yes

No

EN(H4SOw/oOBD)-56

ENGINE (DIAGNOSTICS)

DIAGNOSTICS FOR ENGINE STARTING FAILURE

10

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

Connector & terminal

(B134) No. 13 — Chassis ground:

Is the measured value less than the specified 
value?

1 

Ω

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

Go to step 11.

11

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

Connector & terminal

(B134) No. 14 — (B136) No. 2:

Is the measured value within the specified 
value?

11 — 12 

Ω

Go to step 12.

Repair harness 
and connector.

NOTE:
In this case, repair
the following:
• Open circuit in 
harness between 
ECM and fuel 
injector connector
• Poor contact in 
coupling connector 
(B22)

12

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

Connector & terminal

(B134) No. 14 — Chassis ground:

Is the measured value less than the specified 
value?

1 

Ω

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

Go to step 13.

13

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

Connector & terminal

(B134) No. 15 — (B136) No. 2:

Is the measured value within the specified 
value?

11 — 12 

Ω

Go to step 14.

Repair harness 
and connector.

NOTE:
In this case, repair
the following:
• Open circuit in 
harness between 
ECM and fuel 
injector connector
• Poor contact in 
coupling connector 
(B22)

14

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

Connector & terminal

(B134) No. 15 — Chassis ground:

Is the measured value less than the specified 
value?

1 

Ω

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

Go to step 15.

15

CHECK POOR CONTACT.
Check poor contact in ECM connector.
Is there poor contact in ECM connector?

There is poor contact.

Repair poor con-
tact in ECM con-
nector.

Inspection using 
“General Diagnos-
tic Table”. <Ref. to 
EN(H4SOw/
oOBD)-102, 
INSPECTION, 
General Diagnos-
tic Table.>

Step

Value

Yes

No

EN(H4SOw/oOBD)-57

ENGINE (DIAGNOSTICS)

LIST OF DIAGNOSTIC TROUBLE CODE (DTC)

13.List of Diagnostic Trouble Code (DTC)

A: LIST

Trouble 

code

Item

Contents of diagnosis

Index

11

Crankshaft position sen-
sor

• No signal entered from crankshaft 
position sensor when starter switch is 
ON.
• The harness connector between 
ECM and crankshaft position sensor 
is in short or open.

<Ref. to EN(H4SOw/oOBD)-59, DTC 11 CRANK-
SHAFT POSITION SENSOR, Diagnostic Proce-
dure with Diagnostic Trouble Code (DTC).>

12

Starter switch

• The starter switch signal is abnor-
mal.
• The harness connector between 
ECM and starter switch is in short or 
open.

<Ref. to EN(H4SOw/oOBD)-62, DTC 12 
STARTER SWITCH, Diagnostic Procedure with 
Diagnostic Trouble Code (DTC).>

13

Camshaft position sensor

• No signal entered from camshaft 
position sensor, but signal entered 
from crankshaft position sensor.
• The harness connector between 
ECM and camshaft position sensor is 
in short or open.

<Ref. to EN(H4SOw/oOBD)-64, DTC 13 CAM-
SHAFT POSITION SENSOR, Diagnostic Proce-
dure with Diagnostic Trouble Code (DTC).>

21

Engine coolant tempera-
ture sensor

• The engine coolant temperature 
sensor signal is abnormal.
• The harness connector between 
ECM and engine coolant temperature 
sensor is in short or open.

<Ref. to EN(H4SOw/oOBD)-67, DTC 21 ENGINE 
COOLANT TEMPERATURE SENSOR, Diagnos-
tic Procedure with Diagnostic Trouble Code 
(DTC).>

22

Knock sensor

• The knock sensor signal is abnor-
mal.
• The harness connector between 
ECM and knock sensor is in short or 
open.

<Ref. to EN(H4SOw/oOBD)-71, DTC 22 KNOCK 
SENSOR, Diagnostic Procedure with Diagnostic 
Trouble Code (DTC).>

24

Idle air control solenoid 
valve

• The idle air control solenoid valve is 
not in function.
• The harness connector between 
ECM and idle air control solenoid 
valve is in short or open.

<Ref. to EN(H4SOw/oOBD)-73, DTC 24 IDLE AIR 
CONTROL SOLENOID VALVE, Diagnostic Pro-
cedure with Diagnostic Trouble Code (DTC).>

26

Intake temperature sen-
sor

• The intake air temperature sensor 
signal is abnormal.
• The harness connector between 
ECM and intake air temperature sen-
sor is in short or open.

<Ref. to EN(H4SOw/oOBD)-76, DTC 26 INTAKE 
AIR TEMPERATURE SENSOR, Diagnostic Pro-
cedure with Diagnostic Trouble Code (DTC).>

31

Throttle position sensor

• The throttle position sensor signal 
is abnormal.
• The throttle position sensor is 
installed abnormally.
• The harness connector between 
ECM and throttle position sensor is in 
short or open.

<Ref. to EN(H4SOw/oOBD)-79, DTC 31 THROT-
TLE POSITION SENSOR, Diagnostic Procedure 
with Diagnostic Trouble Code (DTC).>

32

Oxygen sensor

• The oxygen sensor is not in func-
tion.
• The harness connector between 
ECM and oxygen sensor is in short or 
open.

<Ref. to EN(H4SOw/oOBD)-81, DTC 32 OXY-
GEN SENSOR, Diagnostic Procedure with Diag-
nostic Trouble Code (DTC).>

33

Vehicle speed signal 

• The vehicle speed signal is abnor-
mal.
• The harness connector between 
ECM and vehicle speed sensor is in 
short or open.

<Ref. to EN(H4SOw/oOBD)-84, DTC 33 VEHI-
CLE SPEED SIGNAL, Diagnostic Procedure with 
Diagnostic Trouble Code (DTC).>