Subaru IMPREZA 2004 Service Manual page 70

ENGINE (DIAGNOSTICS)
Step
6 CHECK HARNESS BETWEEN ECM AND IG-
NITION COIL & IGNITOR ASSY CONNEC-
TOR.
1)Turn the ignition switch to OFF.
2)Disconnect the connector from ECM.
3)Disconnect the connector from ignition coil &
ignitor ASSY.
4)Measure the resistance of harness between
ECM and ignition coil & ignitor ASSY connec-
tor.
Connector & terminal
1.6 L: (B134) No. 33 — (E12) No. 4:
2.0 L: (B134) No. 33 — (E12) No. 1:
1.6 L: (B134) No. 32 — (E12) No. 2:
2.0 L: (B134) No. 32 — (E12) No. 4:
7 CHECK HARNESS BETWEEN ECM AND IG-
NITION COIL & IGNITOR ASSY CONNEC-
TOR.
Measure the resistance of harness between
ECM and engine ground.
Connector & terminal:
(B134) No. 33 — Engine ground:
(B134) No. 32 — Engine ground:
8 CHECK POOR CONTACT.
Check poor contact in ECM connector.
Diagnostics for Engine Starting Failure
Is the resistance less than 1
Ω?
Is the resistance more than 1
MΩ?
Is there poor contact in ECM
connector?
EN(H4SO)(diag)-68
Check
Go to step 7.
Go to step 8.
Repair poor con-
tact in ECM con-
nector.
Yes No
Repair harness
and connector.
NOTE:
In this case, repair
the following:
• Open circuit in
harness between
ECM and ignition
coil & ignitor ASSY
connector
• Poor contact in
coupling connector
Repair ground
short circuit in har-
ness between
ECM and ignition
coil & ignitor ASSY
connector.
Check fuel pump
circuit. <Ref. to
EN(H4SO)(diag)-
69, FUEL PUMP
CIRCUIT, Diag-
nostics for Engine
Starting Failure.>