Subaru FORESTER 2001 Service Manual page 75

DIAGNOSTICS FOR ENGINE STARTING FAILURE
Engine (Diagnostics)
No.
3 CHECK POWER SUPPLY CIRCUIT FOR
IGNITION COIL & IGNITOR ASSEMBLY.
1) Turn ignition switch to OFF.
2) Disconnect connector from ignition coil &
ignitor assembly.
3) Turn ignition switch to ON.
4) Measure power supply voltage between
ignition coil & ignitor assembly connector and
engine ground.
Connector & terminal
(E31) No. 3 (+) — Engine ground (−):
(E32) No. 3 (+) — Engine ground (−):
(E33) No. 3 (+) — Engine ground (−):
(E34) No. 3 (+) — Engine ground (−):
4 CHECK HARNESS OF IGNITION COIL &
IGNITOR ASSEMBLY GROUND CIRCUIT.
1) Turn ignition switch to OFF.
2) Measure resistance between ignition coil &
ignitor assembly connector and engine
ground.
Connector & terminal
(E31) No. 2 — Engine ground:
(E32) No. 2 — Engine ground:
(E33) No. 2 — Engine ground:
(E34) No. 2 — Engine ground:
5 CHECK HARNESS BETWEEN ECM AND
IGNITION COIL & IGNITOR ASSEMBLY
CONNECTOR.
1) Turn ignition switch to OFF.
2) Disconnect connector from ECM.
3) Disconnect connector from ignition coil &
ignitor assembly.
4) Measure resistance of harness between
ECM and ignition coil & ignitor assembly con-
nector.
Connector & terminal
(B136) No. 21 — (E34) No. 1:
(B136) No. 22 — (E33) No. 1:
(B136) No. 23 — (E32) No. 1:
(B136) No. 24 — (E31) No. 1:
6 CHECK HARNESS BETWEEN ECM AND
IGNITION COIL & IGNITOR ASSEMBLY
CONNECTOR.
Measure resistance of harness between ECM
and engine ground.
Connector & terminal:
(B136) No. 21 — Engine ground:
(B136) No. 22 — Engine ground:
(B136) No. 23 — Engine ground:
(B136) No. 24 — Engine ground:
7 CHECK POOR CONTACT.
Check poor contact in ECM connector.
Step
Is the voltage more than 10
V?
Is the resistance between
less than 5 Ω?
Is the resistance less than
1 Ω?
Is the resistance more than
1 MΩ?
Is there poor contact in
ECM connector?
EN(DOHC TURBO)-74
Check Yes
Go to step 4.
Go to step 5.
Go to step 6.
Go to step 7.
Repair poor con-
tact in ECM con-
nector.
No
Repair harness
and connector.
NOTE:
In this case,
repair the follow-
ing:
¼ Open circuit in
harness between
ignition coil & igni-
tor assembly, and
ignition switch
connector
¼ Poor contact in
coupling connec-
tors
Repair harness
and connector.
NOTE:
In this case,
repair the follow-
ing:
¼ Open circuit in
harness between
ignition coil & igni-
tor assembly con-
nector and engine
grounding termi-
nal
Repair harness
and connector.
NOTE:
In this case,
repair the follow-
ing:
¼ Open circuit in
harness between
ECM and ignition
coil & ignitor
assembly connec-
tor
¼ Poor contact in
coupling connec-
tor
Repair ground
short circuit in
harness between
ECM and ignition
coil & ignitor
assembly connec-
tor.
Replace ignition
coil and ignitor
assembly.