Subaru Legacy III (2000-2003 year). Manual - part 492

EN(H4DOSTC)-138

ENGINE (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

AA:DTC P0328 — KNOCK SENSOR 1 CIRCUIT HIGH INPUT (BANK 1 OR SIN-

GLE SENSOR) —

• TROUBLE SYMPTOM:

• Poor driving performance
• Knocking occurs.

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:

E1

E14

B20

 KNOCK
SENSOR

2

6

B135 ECM

22

4

E

E14

1 2

1 2

3 4

5

6

7

8

9

10

B20

B135

5 6

7 8

2

1

9

4

3

10

24

22

23

25

11 12 13 14 15

26 27 28

16 17 18 19

20 21

EN-00941

EN(H4DOSTC)-139

ENGINE (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

Step

Value

Yes

No

1

CHECK HARNESS BETWEEN KNOCK SEN-
SOR AND ECM CONNECTOR.
Measure the resistance of harness between 
ECM connector and chassis ground.

Connector & terminal

(B135) No. 4 — Chassis ground:

Is the measured value less than the specified 
value?

400 k

Ω

Go to step 2.

Go to step 3.

2

CHECK KNOCK SENSOR.
1) Disconnect the connector from knock sen-

sor.

2) Measure the resistance between knock 

sensor connector terminal and engine 
ground.

Terminal

No. 2 — Engine ground:

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

400 k

Ω

Replace the knock 
sensor.  <Ref. to 
FU(H4DOSTC)-
31, Knock Sen-
sor.>

Repair the ground 
short circuit in har-
ness between 
knock sensor con-
nector and ECM 
connector.

NOTE:
The harness be-
tween both con-
nectors is
shielded. Repair
the short circuit of
harness together
with shield.

3

CHECK INPUT SIGNAL FOR ECM.
1) Connect the connectors to ECM and knock 

sensor.

2) Turn the ignition switch to ON.
3) Measure the voltage between ECM and 

chassis ground.

Connector & terminal

(B135) No. 4 (+) — Chassis ground (

−−−−

):

Does the measured value exceed the spec-
ified value?

2 V

Even if MI lights 
up, the circuit has 
returned to a nor-
mal condition at 
this time. (How-
ever, the possibil-
ity of poor contact 
still remains.)

NOTE:
In this case, repair
the following:
• Poor contact in 
knock sensor con-
nector
• Poor contact in 
ECM connector
• Poor contact in 
coupling connector

Repair the poor 
contact in ECM 
connector.

EN(H4DOSTC)-140

ENGINE (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

AB:DTC P0335 — CRANKSHAFT POSITION SENSOR “A” CIRCUIT —

• TROUBLE SYMPTOM:

• Engine stalls.
• 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:

2

1

E1

E10

B20

CRANKSHAFT
   POSITION
    SENSOR

2

1

B135 ECM

11

21

2

E

E10

1 2

1 2

3 4

5

6

7

8

9

10

B20

B135

5 6

7 8

2

1

9

4

3

10

24

22

23

25

11 12 13 14 15

26 27 28

16 17 18 19

20 21

EN-00942

EN(H4DOSTC)-141

ENGINE (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

Step

Value

Yes

No

1

CHECK HARNESS BETWEEN CRANK-
SHAFT POSITION SENSOR AND ECM CON-
NECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from crankshaft 

position sensor.

3) Measure the resistance of harness 

between crankshaft position sensor con-
nector and engine ground.

Connector & terminal

(E10) No. 1 — Engine ground:

Does the measured value exceed the spec-
ified value?

100 k

Ω

Repair the har-
ness and connec-
tor.

NOTE:
In this case, repair
the following:
• Open circuit in 
harness between 
crankshaft posi-
tion sensor and 
ECM connector
• Poor contact in 
ECM connector
• Poor contact in 
coupling connector

Go to step 2.

2

CHECK HARNESS BETWEEN CRANK-
SHAFT POSITION SENSOR AND ECM CON-
NECTOR.
Measure the resistance of harness between 
crankshaft position sensor connector and 
engine ground.

Connector & terminal

(E10) No. 1 — Engine ground:

Is the measured value less than the specified 
value?

10 

Ω

Repair the ground 
short circuit in har-
ness between 
crankshaft posi-
tion sensor and 
ECM connector.

NOTE:
The harness be-
tween both con-
nectors are
shielded. Repair
the ground short
circuit in harness
together with
shield.

Go to step 3.

3

CHECK HARNESS BETWEEN CRANK-
SHAFT POSITION SENSOR AND ECM CON-
NECTOR.
Measure the resistance of harness between 
crankshaft position sensor connector and 
engine ground.

Connector & terminal

(E10) No. 2 — Engine ground:

Is the measured value less than the specified 
value?

5 

Ω

Go to step 4.

Repair the har-
ness and connec-
tor.

NOTE:
In this case, repair
the following:
• Open circuit in 
harness between 
crankshaft posi-
tion sensor and 
ECM connector
• Poor contact in 
ECM connector
• Poor contact in 
coupling connector

4

CHECK CONDITION OF CRANKSHAFT PO-
SITION SENSOR.
Is the crankshaft position sensor installation 
bolt tightened securely?

Tightened securely.

Go to step 5.

Tighten the crank-
shaft position sen-
sor installation bolt 
securely.

5

CHECK CRANKSHAFT POSITION SENSOR.
1) Remove the crankshaft position sensor.
2) Measure the resistance between connector 

terminals of crankshaft position sensor.

Terminals

No. 1 — No. 2:

Is the measured value within the specified 
value?

1 — 4 k

Ω

Repair the poor 
contact in crank-
shaft position sen-
sor connector.

Replace the crank-
shaft position sen-
sor.  <Ref. to 
FU(H4DOSTC)-
29, Crankshaft 
Position Sensor.>