2004 SUBARU FORESTER sensor

EN(H4DOTC 2.5)-131
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
AA:DTC P0327 KNOCK SENSOR 1 CIRCUIT LOW INPUT (BANK 1 OR SINGLE
SENSOR)
DTC DETECTING CONDITION:
Immediately at fault recognition
TROUBLE SYMPTOM:
 Poor driving performance
 Knocking occurs.
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode OPERATION, Clear Memory Mode.> and Inspection Mode Inspection Mode.>.
WIRING DIAGRAM:
EN-02028
E1E14
B20
2 6
B136 ECM
33 25
E
E14
12
12 34
56
7
89
10
B20
B136
56
782 1
94 3
10
24 22 23 2511 12 13
1415
26 27
2816
17 18 19 20 21
33 34 29
32 30
31 35
KNOCK
SENSOR

EN(H4DOTC 2.5)-132
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step Check Yes No
1 CHECK HARNESS BETWEEN KNOCK SEN-
SOR AND ECM CONNECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from ECM.
3) Measure the resistance between ECM har-
ness connector and chassis ground.
Connector & terminal
(B136) No. 25 — Chassis ground:Is the resistance more than
700 kΩ?Go to step 2.Repair the harness
and connector.
N
OTE:
In this case repair
the following:
 Open circuit in
harness between
knock sensor and
ECM connector
 Poor contact in
knock sensor con-
nector
 Poor contact in
coupling connector
2 CHECK KNOCK SENSOR.
1) Disconnect the connector from knock sensor.
2) Measure the resistance between knock
sensor connector terminal and engine ground.
Connector & terminal
(E14) No. 2 — Engine ground:Is the resistance more than
700 kΩ?Go to step 3.Repair the harness
and connector.
NOTE:
In this case repair
the following:
 Poor contact in
knock sensor con-
nector
 Poor contact in
coupling connector
3 CHECK CONDITION OF KNOCK SENSOR
INSTALLATION.Is the knock sensor installation
bolt tightened securely?Replace the knock
sensor. FU(H4DOTC 2.5)-
29, Knock Sen-
sor.>Tighten knock sen-
sor installation bolt
securely.

EN(H4DOTC 2.5)-133
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
AB:DTC P0328 KNOCK SENSOR 1 CIRCUIT HIGH INPUT (BANK 1 OR SINGLE
SENSOR)
DTC DETECTING CONDITION:
Immediately at fault recognition
TROUBLE SYMPTOM:
 Poor driving performance
 Knocking occurs.
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode OPERATION, Clear Memory Mode.> and Inspection Mode Inspection Mode.>.
WIRING DIAGRAM:
EN-02028
E1E14
B20
2 6
B136 ECM
33 25
E
E14
12
12 34
56
7
89
10
B20
B136
56
782 1
94 3
10
24 22 23 2511 12 13
1415
26 27
2816
17 18 19 20 21
33 34 29
32 30
31 35
KNOCK
SENSOR

EN(H4DOTC 2.5)-134
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step Check 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
(B136) No. 25 — Chassis ground:Is the resistance less than 400
kΩ?Go to step 2.Go to step 3.
2 CHECK KNOCK SENSOR.
1) Disconnect the connector from knock sensor.
2) Measure the resistance between knock
sensor connector terminal and engine ground.
Te r m i n a l s
No. 2 — Engine ground:Is the resistance less than 400
kΩ?Replace the knock
sensor. FU(H4DOTC 2.5)-
29, Knock Sen-
sor.>Repair ground short
circuit in harness
between knock sen-
sor connector and
ECM connector.
N
OTE:
The harness be-
tween both con-
nectors are
shielded. Repair
short circuit in har-
ness covered with
shield.
3 CHECK INPUT SIGNAL FROM 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
(B136) No. 25 (+) — Chassis ground (
−):Is the voltage more than 2 V? Even if the mal-
function indicator
light illuminates,
the circuit has
returned to a nor-
mal condition at
this time. (How-
ever, the possibility
of poor contact still
remains.)
N
OTE:
In this case repair
the following:
 Poor contact in
knock sensor con-
nector
 Poor contact in
ECM connector.
 Poor contact in
coupling connectorRepair the poor
contact in ECM
connector.

EN(H4DOTC 2.5)-135
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
AC:DTC P0335 CRANKSHAFT POSITION SENSOR “A” CIRCUIT
DTC DETECTING CONDITION:
Immediately at fault recognition
TROUBLE SYMPTOM:
 Engine stalls.
 Failure of engine to start
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode OPERATION, Clear Memory Mode.> and Inspection Mode Inspection Mode.>.
WIRING DIAGRAM:
EN-01829
E1E10
B20 CRANKSHAFT
POSITION
SENSOR
2
1 2
1
B135 ECM
22
31 10
E
E10
12
12 34
56
7
89
10
B20
B135
567
82 1
94 3
10
24 22 23 2511 12 13 14 15
26 27
2816 17 18 19
20 21
29 30 31 32 33 34 35

EN(H4DOTC 2.5)-136
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step Check 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 the crank-
shaft position sensor.
3) Measure the resistance of harness
between crankshaft position sensor connector
and engine ground.
Connector & terminal
(E10) No. 1 — Engine ground:Is the resistance more than
100 kΩ?Repair the harness
and connector.
N
OTE:
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 connectorGo 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 resistance more than 1
MΩ?Go to step 3.Repair ground short
circuit in harness
between crankshaft
position sensor and
ECM connector.
NOTE:
The harness be-
tween both con-
nectors are
shielded. Repair
ground short circuit
in harness togeth-
er with shield.
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 resistance less than 5 Ω? Go to step 4.Repair the harness
and connector.
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 sen-
sor installation bolt 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.
Te r m i n a l s
No. 1 — No. 2:Is the resistance 1 — 4 kΩ? Repair poor con-
tact in crankshaft
position sensor
connector.Replace the crank-
shaft position sen-
sor. FU(H4DOTC 2.5)-
27, Crankshaft
Position Sensor.>

EN(H4DOTC 2.5)-137
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
AD:DTC P0340 CAMSHAFT POSITION SENSOR “A” CIRCUIT (BANK 1 OR SIN-
GLE SENSOR)
DTC DETECTING CONDITION:
Immediately at fault recognition
TROUBLE SYMPTOM:
 Engine stalls.
 Failure of engine to start
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode OPERATION, Clear Memory Mode.> and Inspection Mode Inspection Mode.>.
WIRING DIAGRAM:
EN-02365
B47 1 2 3 5 4 6
E
E1
B20
B8
3 C35
SBF-5
E35
E1
B20
2E36
B21E2
1
107
3
B9
7
1
B122
2 1
ECM
B136B135 B:
C:
1
8
3412
56
123
4
56
78
9
1011 12
1314 15 16
B21
E36
B47
123
12 34
567
89
10
B20
B136
56
782 1
94 3
10
24 22 23 2511 12 13
1415
26 27
2816
17 18 19 20 21
33 34 29
32 30
31 35
B135
567
82 1
94 3
10
24 22 23 2511 12 13 14 15
26 27
2816 17 18 19
20 21
29 30 31 32 33 34 35
E35
B:C:
MAIN RELAY
BATTERY
CAMSHAFT
POSITION
SENSOR LHCAMSHAFT
POSITION
SENSOR RH
B122
12345678

EN(H4DOTC 2.5)-138
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step Check Yes No
1 CHECK POWER SUPPLY OF CAMSHAFT
POSITION SENSOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from camshaft
position sensor.
3) Measure the voltage between camshaft
position sensor and engine ground.
Connector & terminal
(E36) No. 1 (+) — Engine ground (
−):Is the voltage more than 10 V? Repair the battery
short circuit
between main relay
connector and
camshaft position
sensor connector.Go to step 2.
2 CHECK POWER SUPPLY OF CAMSHAFT
POSITION SENSOR.
1) Turn the ignition switch to ON.
2) Measure the voltage between camshaft
position sensor and engine ground.
Connector & terminal
(E36) No. 1 (+) — Engine ground (
−):Is the voltage more than 10 V? Go to step 3.Repair open or bat-
tery short circuit
between main relay
connector and
camshaft position
sensor connector.
3 CHECK HARNESS BETWEEN CAMSHAFT
POSITION SENSOR AND ECM.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from ECM.
3) Measure the resistance between camshaft
position sensor and ECM.
Connector & terminal
(E36) No. 2 — (B135) No. 9:
(E36) No. 3 — (B136) No. 35:Is the resistance less than 1
Ω?Go to step 4.Repair open circuit
between camshaft
position sensor
and ECM.
4 CHECK HARNESS BETWEEN CAMSHAFT
POSITION SENSOR AND ECM.
Measure the resistance between camshaft
position sensor and engine ground.
Connector & terminal
(E36) No. 2 — Engine ground:
(E36) No. 3 — Engine ground:Is the resistance more than 1
MΩ?Go to step 5.Repair ground short
circuit between
camshaft position
sensor and ECM.
5 CHECK CONDITION OF CAMSHAFT POSI-
TION SENSOR.Is the camshaft position sensor
installation bolt tightened
securely?Go to step 6.Tighten the cam-
shaft position sen-
sor installation bolt
securely.
6 CHECK CAMSHAFT POSITION SENSOR.
Check waveform of camshaft position sensor.
Module (ECM) I/O Signal.>Is there any abnormality in
waveform?Replace the cam-
shaft position sen-
sor. FU(H4DOTC 2.5)-
28, Camshaft
Position Sensor.>Go to step 7.
7 CHECK POOR CONTACT.
Check poor contact in ECM connector.Is there poor contact in ECM
connector?Repair the poor
contact in ECM
connector.Replace the ECM.
FU(H4DOTC 2.5)-
41, Engine Con-
trol Module
(ECM).>