Subaru 2002 IMPREZA Service Manual page 888

DIAGNOSTICS FOR ENGINE STARTING FAILURE
ENGINE (DIAGNOSTICS)
Step
6 CHECK INPUT SIGNAL FOR IGNITION COIL
& IGNITOR ASSEMBLY.
Check if the voltage varies synchronously with
engine speed when cranking, while monitoring
voltage between ignition coil & ignitor assem-
bly connector and engine ground.
Connector & terminal
•1.6 L
(E12) No. 4 (+) — Engine ground (–):
•2.0 L and 2.5 L
(E12) No. 1 (+) — Engine ground (–):
7 CHECK INPUT SIGNAL FOR IGNITION COIL
& IGNITOR ASSEMBLY.
Check if the voltage varies synchronously with
engine speed when cranking, while monitoring
voltage between ignition coil & ignitor assem-
bly connector and engine ground.
Connector & terminal
•1.6 L
(E12) No. 2 (+) — Engine ground (–):
•2.0 L and 2.5 L
(E12) No. 4 (+) — Engine ground (–):
8 CHECK HARNESS BETWEEN ECM AND IG-
NITION COIL & IGNITOR ASSEMBLY CON-
NECTOR.
1)Disconnect the connector from ECM.
2)Measure the resistance of harness between
ECM and ignition coil & ignitor assembly con-
nector.
Connector & terminal
•1.6 L
(B134) No. 26 — (E12) No. 2:
•2.0 L and 2.5 L
(B134) No. 26 — (E12) No. 4:
9 CHECK HARNESS BETWEEN ECM AND IG-
NITION COIL & IGNITOR ASSEMBLY CON-
NECTOR.
Measure the resistance of harness between
ECM and ignition coil & ignitor assembly con-
nector.
Connector & terminal
•1.6 L
(B134) No. 25 — (E12) No. 4:
•2.0 L and 2.5 L
(B134) No. 25 — (E12) No. 1:
Check
Is the voltage more than 10 V? Go to step 7.
Is the voltage more than 10 V? Go to step 8.
Is the resistance less than 1
Ω?
Is the resistance less than 1
Ω?
EN(w/oOBD)-54
Yes
Replace the igni-
tion coil & ignitor
assembly.
Replace the igni-
tion coil & ignitor
assembly.
Go to step 9. Repair the har-
ness and connec-
tor.
NOTE:
In this case, repair
the following:
• Open circuit in
harness between
ECM and ignition
coil & ignitor
assembly connec-
tor
• Poor contact in
a coupling connec-
tor (B22)
Go to step 10. Repair the har-
ness and connec-
tor.
NOTE:
In this case, repair
the following:
• Open circuit in
harness between
ECM and ignition
coil & ignitor
assembly connec-
tor
• Poor contact in
a coupling connec-
tor (B22)
No