Subaru Impreza 2003 Service Manual page 1717

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Step
8 CHECK INPUT SIGNAL FOR TCM.
1)Connect the connector to transmission.
2)Warm-up the transmission until ATF temper-
ature is about 80°C (176°F).
NOTE:
If ambient temperature is below 0°C (32°F),
drive the vehicle until ATF reaches its operating
temperature.
3)Measure the voltage between TCM connec-
tor terminal.
Connector & terminal
(B54) No. 11 (+) — No. 20 ( − − − − ):
9 CHECK INPUT SIGNAL FOR TCM USING
SUBARU SELECT MONITOR.
1)Connect the connector to transmission.
2)Turn the ignition switch to ON (engine OFF).
10 CHECK POOR CONTACT.
AUTOMATIC TRANSMISSION (DIAGNOSTICS)
Check
Is the voltage 0.4 — 0.9 V?
Does the ATF temperature
gradually decrease?
Is there poor contact in ATF
temperature sensor circuit?
4AT-47
Yes
Even if the Go to step 10.
POWER indicator
lights up, the cir-
cuit has returned
to a normal condi-
tion at this time.
Temporary poor
contact of the con-
nector or harness
may be the cause.
Repair the har-
ness or contact in
ATF temperature
sensor and trans-
mission connector.
Even if the Go to step 10.
POWER indicator
lights up, the cir-
cuit has returned
to a normal condi-
tion at this time.
Temporary poor
contact of the con-
nector or harness
may be the cause.
Repair the har-
ness or contact in
ATF temperature
sensor and trans-
mission connector.
Repair the poor Replace the TCM.
contact. <Ref. to 4AT-70,
Transmission Con-
trol Module
(TCM).>
No