Subaru Legacy 2002 Service Manual page 920

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
No.
1 CHECK INPUT SIGNAL FOR ECM.
1) Turn ignition switch to ON.
2) Measure voltage between ECM and chas-
sis ground in selector lever "N" and "P" posi-
tions.
Connector & terminal
(B135) No. 26 (+) — Chassis ground
(−):
2 CHECK POOR CONTACT.
Check poor contact in ECM connector.
3 CHECK HARNESS BETWEEN ECM AND
INHIBITOR SWITCH CONNECTOR.
1) Turn ignition switch to OFF.
2) Disconnect connectors from ECM and
inhibitor switch.
3) Measure resistance of harness between
ECM and inhibitor switch connector.
Connector & terminal
(B135) No. 26 — (T7) No. 12:
4 CHECK INHIBITOR SWITCH GROUND
LINE.
Measure resistance of harness between
inhibitor switch connector and engine ground.
Connector & terminal
(T7) No. 12 — Engine ground:
5 CHECK HARNESS BETWEEN ECM AND
TRANSMISSION HARNESS CONNECTOR.
Measure resistance of harness between ECM
connector and chassis ground.
Connector & terminal
(B135) No. 26 — Chassis ground:
6 CHECK POOR CONTACT.
Check poor contact in ECM connector.
Step
Is the voltage less than 1
V?
Is there poor contact in
ECM connector?
Is the resistance less than
1 Ω?
Is the resistance less than
5 Ω?
Is the resistance less than
10 Ω?
Is there poor contact in
ECM connector?
EN(w/oOBD)-109
Check Yes
Go to step 2.
Repair poor con-
tact in ECM con-
nector.
Go to step 4.
Go to step 5.
Repair ground
short circuit in
harness between
ECM and trans-
mission harness
connector.
Repair poor con-
tact in ECM con-
nector.
Engine (Diagnostics)
No
Go to step 3.
Go to step 3.
Repair harness
and connector.
NOTE:
In this case,
repair the follow-
ing:
¼ Open circuit in
harness between
ECM and inhibitor
switch connector
¼ Poor contact in
coupling connec-
tor (B12)
¼ Poor contact in
inhibitor switch
connector
¼ Poor contact in
ECM connector
Repair open cir-
cuit in inhibitor
switch ground
line.
Go to step 6.
Replace ECM.
<Ref. to FU(w/
oOBD)-45, Engine
Control Module.>