Subaru IMPREZA 2004 Service Manual page 84

Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step
1 CHECK HARNESS BETWEEN CAMSHAFT
POSITION SENSOR AND ECM CONNEC-
TOR.
1)Turn the ignition switch to OFF.
2)Disconnect the connector from camshaft
position sensor.
3)Measure the resistance of harness between
camshaft position sensor connector and
engine ground.
Connector & terminal
(E15) No. 1 — Engine ground:
2 CHECK HARNESS BETWEEN CAMSHAFT
POSITION SENSOR AND ECM CONNEC-
TOR.
Measure the resistance of harness between
camshaft position sensor connector and
engine ground.
Connector & terminal
(E15) No. 1 — Engine ground:
3 CHECK HARNESS BETWEEN CAMSHAFT
POSITION SENSOR AND ECM CONNEC-
TOR.
Measure the resistance of harness between
camshaft position sensor connector and
engine ground.
Connector & terminal
(E15) No. 2 — Engine ground:
4 CHECK CONDITION OF CAMSHAFT POSI-
TION SENSOR.
5 CHECK CAMSHAFT POSITION SENSOR.
1)Remove the camshaft position sensor.
2)Measure the resistance between connector
terminals of camshaft position sensor.
Terminals
No. 1 — No. 2:
Check
Is the resistance more than
100 kΩ?
Is the resistance less than 10
Ω?
Is the resistance less than 5
Ω?
Is the camshaft position sensor
installation bolt tightened
securely?
Is the resistance 1 — 4 kΩ?
EN(H4SO)(diag)-161
ENGINE (DIAGNOSTICS)
Yes
Repair harness Go to step 2.
and connector.
NOTE:
In this case, repair
the following:
• Open circuit in
harness between
camshaft position
sensor and ECM
connector
• Poor contact in
ECM connector
• Poor contact in
coupling connector
Repair ground Go to step 3.
short circuit in har-
ness between
camshaft 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.
Go to step 4. Repair harness
and connector.
NOTE:
In this case, repair
the following:
• Open circuit in
harness between
camshaft position
sensor and ECM
connector
• Poor contact in
ECM connector
• Poor contact in
coupling connector
Go to step 5. Tighten camshaft
position sensor
installation bolt
securely.
Repair poor con- Replace the cam-
tact in camshaft shaft position sen-
position sensor sor. <Ref. to
connector. FU(H4SO)-29,
Camshaft Position
Sensor.>
No