Subaru Impreza 2003 Service Manual page 1798

DIAGNOSTIC PROCEDURE WITHOUT DIAGNOSTIC TROUBLE CODE (DTC)
AUTOMATIC TRANSMISSION (DIAGNOSTICS)
Step
22 CHECK HARNESS CONNECTOR BETWEEN
TCM AND SPORT SHIFT SWITCH.
1)Disconnect the connector from TCM.
2)Measure the resistance of harness between
TCM connector and SPORT shift switch con-
nector.
Connector & terminal
(B237) No. 1 — (B55) No. 2:
23 CHECK HARNESS CONNECTOR BETWEEN
TCM AND SPORT SHIFT SWITCH.
1)Disconnect the steering roll connector.
2)Measure the resistance of harness between
SPORT shift switch connector and chassis
ground.
Connector & terminal
(B237) No. 1 — Chassis ground:
24 CHECK INPUT SIGNAL FOR TCM.
1)Connect the all connectors.
2)Turn the ignition switch to ON. (Engine is
stopped.)
3)Measure the signal voltage for TCM.
Connector & terminal
(B55) No. 2 (+) — Chassis ground (–):
25 CHECK INPUT SIGNAL FOR TCM.
1)Move the select lever to shift up side.
2)Measure the signal voltage for TCM.
Connector & terminal
(B55) No. 2 (+) — Chassis ground (–):
26 CHECK POOR CONTACT.
Check
Is the resistance less than 1
Ω?
Is the resistance more than 1
MΩ?
Is the voltage more than 9 V?
Is the voltage less than 1 V?
Is there poor contact in
SPORT shift switch circuit?
4AT-128
Yes
Go to step 23. Repair the open
circuit in harness
between SPORT
shift switch con-
nector and TCM
connector and
poor contact in
coupling connec-
tor.
Go to step 24. Repair the short
circuit in harness
between SPORT
shift switch con-
nector and TCM
connector.
Go to step 25. Replace the TCM.
<Ref. to 4AT-70,
Transmission Con-
trol Module
(TCM).>
Even if the Go to step 26.
POWER indicator
lights up, the cir-
cuit has returned
to a normal condi-
tion at this time. A
temporary poor
contact of the con-
nector or harness
may be the cause.
Repair the har-
ness or connector
in sport shift switch
circuit.
Repair the poor Replace the TCM.
contact. <Ref. to 4AT-70,
Transmission Con-
trol Module
(TCM).>
No