Subaru 2009 IMPREZA Service Manual page 2065

Diagnostic Procedure without Diagnostic Trouble Code (DTC)
AUTOMATIC TRANSMISSION (DIAGNOSTICS)
Step
17 CHECK SPORT SHIFT INDICATOR.
1) Set the select lever to – side.
2) Read the SPORT shift indicator display in
combination meter.
18 CHECK TCM.
1) Shift and hold the select lever to – side.
2) Read the "Down Switch" data using Subaru
Select Monitor.
19 CHECK HARNESS CONNECTOR BETWEEN
TCM AND – SWITCH.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from TCM and –
switch.
3) Measure the resistance of harness between
TCM and – switch.
Connector & terminal
(B54) No. 18 — (B117) No. 9:
20 CHECK – SWITCH.
1) Shift and hold the select lever to – side.
2) Measure the resistance between – switch
terminals.
Connector & terminal
(B117) No. 9 — No. 10:
21 CHECK HARNESS CONNECTOR BETWEEN
– SWITCH AND CHASSIS GROUND.
Measure the resistance of harness between –
switch and chassis ground.
Connector & terminal
(B117) No. 10 — Chassis ground:
22 CHECK POOR CONTACT.
Check poor contact of – switch circuit.
23 CHECK TCM.
1) Set the select lever to the center position.
(Tilt the select lever to SPORT mode, and
release the hold.)
2) Read the "Down Switch" data using Subaru
Select Monitor.
24 CHECK HARNESS CONNECTOR BETWEEN
TCM AND – SWITCH.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from TCM and –
switch.
3) Measure the resistance of harness between
TCM and – switch.
Connector & terminal
(B54) No. 18 — Chassis ground:
25 CHECK – SWITCH.
Measure the resistance between – switch termi-
nals.
Connector & terminal
(B117) No. 9 — No. 10:
Check
Is "1" displayed?
Is "ON" displayed?
Is the resistance less than 1 ? Go to step 20.
Is the resistance less than 1 ? Go to step 21.
Is the resistance less than 1 ? Go to step 22.
Is there poor contact of – switch
circuit?
Is "OFF" displayed?
Is the resistance 1 M or
more?
Is the resistance 1 M or
more?
4AT(diag)-80
Yes No
Normal. Finish the Go to step 18.
diagnosis.
Go to step 23. Go to step 19.
Repair the open
circuit of harness
between TCM and
– switch.
Replace the guide
plate assembly.
Repair the open
circuit of harness
between – switch
and chassis
ground.
Repair the poor Replace the TCM.
contact.
Perform the self- Go to step 24.
diagnosis of com-
bination meter.
Go to step 25. Repair the short
circuit of harness
between TCM and
– switch.
Replace the TCM. Replace the guide
plate assembly.