Subaru 2009 IMPREZA Service Manual page 657

Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
Step
1 CHECK SELECT CABLE.
2 CHECK INPUT SIGNAL OF ECM.
1) Turn the ignition switch to ON.
2) Place the select lever in other than "P" range
and "N" range.
3) Measure the voltage between ECM and
chassis ground.
Connector & terminal
(B136) No. 31 (+) — Chassis ground (–):
3 CHECK HARNESS BETWEEN ECM AND
TRANSMISSION HARNESS CONNECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connectors from ECM and
transmission harness connector (T3).
3) Measure the resistance between ECM and
chassis ground.
Connector & terminal
(B136) No. 31 — Chassis ground:
4 CHECK TRANSMISSION HARNESS CON-
NECTOR.
1) Disconnect the connector from inhibitor
switch.
2) Measure the resistance between transmis-
sion harness connector and engine ground.
Connector & terminal
(T3) No. 12 — Engine ground:
Check
Is there any fault in select
cable?
Is the voltage 10 V or more?
Is the resistance 1 M or
more?
Is the resistance 1 M or
more?
EN(H4SO)(diag)-240
Yes No
Repair or adjust Go to step 2.
the select cable.
<Ref. to CS-25,
Select Cable.>
Repair the poor Go to step 3.
contact of ECM
connector.
Go to step 4. Repair the ground
short circuit of har-
ness between
ECM and transmis-
sion harness con-
nector.
Replace the inhibi- Repair short cir-
tor switch. <Ref. to cuit to ground in
4AT-48, Inhibitor harness between
Switch.> transmission har-
ness connector
and inhibitor switch
connector.