Subaru 2009 IMPREZA Service Manual page 2042

Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step
1 CHECK HARNESS CONNECTOR BETWEEN
TCM AND TRANSMISSION.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from transmission
and TCM.
3) Measure the resistance of harness between
TCM connector and transmission connector.
Connector & terminal
(B55) No. 3 — (B11) No. 2:
(B55) No. 4 — (B11) No. 1:
2 CHECK HARNESS CONNECTOR BETWEEN
TCM AND CHASSIS GROUND.
Measure the resistance of harness between
TCM connector and chassis ground.
Connector & terminal
(B55) No. 3 — Chassis ground:
(B55) No. 4 — Chassis ground:
3 CHECK LINE PRESSURE LINEAR SOLE-
NOID.
Measure the resistance between transmission
connector receptacle's terminals.
Connector & terminal
(T4) No. 1 — No. 2:
4 CHECK LINE PRESSURE LINEAR SOLE-
NOID (IN TRANSMISSION).
1) Remove the transmission connector from
bracket.
2) Drain the automatic transmission fluid.
CAUTION:
Do not drain ATF until it cools down.
3) Remove the oil pan.
4) Disconnect the connector from the control
valve body.
5) Measure the resistance of line pressure lin-
ear solenoid connector terminals.
Connector & terminal
(AT2) No. 5 — No. 10:
5 CHECK HARNESS CONNECTOR BETWEEN
TRANSMISSION AND LINE PRESSURE LIN-
EAR SOLENOID.
Measure the resistance of harness between
line pressure linear solenoid and transmission
connector.
Connector & terminal
(T4) No. 2 — (AT2) No. 10:
(T4) No. 1 — (AT2) No. 5:
6 CHECK HARNESS CONNECTOR BETWEEN
TRANSMISSION AND LINE PRESSURE LIN-
EAR SOLENOID.
Measure the resistance of harness between
transmission connector and transmission
ground.
Connector & terminal
(T4) No. 1 — Transmission ground:
(T4) No. 2 — Transmission ground:
AUTOMATIC TRANSMISSION (DIAGNOSTICS)
Check
Is the resistance less than 1 ? Go to step 2.
Is the resistance 1 M or
more?
Is the resistance 4.0 — 8.0 ? Replace the TCM.
Is the resistance 4.0 — 8.0 ? Go to step 5.
Is the resistance less than 1 ? Go to step 6.
Is the resistance 1 M or
more?
4AT(diag)-57
Yes No
Repair the open
circuit of harness
between TCM and
transmission con-
nector.
Go to step 3. Repair the short
circuit of harness
between TCM and
transmission con-
nector.
Go to step 4.
<Ref. to 4AT-63,
Transmission Con-
trol Module
(TCM).>
Replace the con-
trol valve body.
<Ref. to 4AT-58,
Control Valve
Body.>
Repair the open
circuit of harness
between line pres-
sure linear sole-
noid and
transmission con-
nector.
Check the har- Repair the short
nesses or connec- circuit of harness
tors between line between line pres-
pressure linear sure linear sole-
solenoid and trans- noid and
mission, and repair transmission con-
the defective part. nector.