Subaru Impreza 2003 Service Manual page 1716

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
AUTOMATIC TRANSMISSION (DIAGNOSTICS)
Step
2 CHECK HARNESS CONNECTOR BETWEEN
TCM AND ATF TEMPERATURE SENSOR.
Measure the resistance of harness between
TCM and transmission connector.
Connector & terminal
(B54) No. 11 — (B11) No. 11:
3 CHECK HARNESS CONNECTOR BETWEEN
TCM AND ATF TEMPERATURE SENSOR.
Measure the resistance of harness between
TCM connector and chassis ground.
Connector & terminal
(B54) No. 20 — Chassis ground:
4 CHECK HARNESS CONNECTOR BETWEEN
TCM AND ATF TEMPERATURE SENSOR.
Measure the resistance of harness between
TCM connector and chassis ground.
Connector & terminal
(B54) No. 11 — Chassis ground:
5 CHECK ATF TEMPERATURE SENSOR.
1)Turn the ignition switch to OFF.
2)Connect the connectors to transmission and
TCM.
3)Turn the ignition switch to ON and start
engine.
4)Warm-up the transmission until ATF temper-
ature reaches to 80°C (176°F).
NOTE:
If ambient temperature is below 0°C (32°F),
drive the vehicle until ATF reaches its operating
temperature.
5)Disconnect the connector from transmission.
6)Measure the resistance between transmis-
sion connector terminals.
Connector & terminal
(T4) No. 11 — No. 12:
6 CHECK ATF TEMPERATURE SENSOR.
1)Turn the ignition switch to ON (engine OFF).
2)Measure the resistance between transmis-
sion connector terminals.
Connector & terminal
(T4) No. 11 — No. 12:
7 PREPARE SUBARU SELECT MONITOR.
Check
Is the resistance less than 1
Ω?
Is the resistance more than 1
MΩ?
Is the resistance more than 1
MΩ?
Is the resistance 275 — 375
Ω?
Does the resistance value
increase while ATF tempera-
ture decreases?
Do you have a Subaru Select
Monitor?
4AT-46
Yes
Go to step 3. Repair the open
circuit in harness
between TCM and
transmission con-
nector.
Go to step 4. Repair the short
circuit in harness
between TCM and
transmission con-
nector.
Go to step 5. Repair the short
circuit in harness
between TCM and
transmission con-
nector.
Go to step 6. Replace the ATF
temperature sen-
sor. <Ref. to 4AT-
64, Shift Sole-
noids, Duty Sole-
noids and ATF
Temperature Sen-
sor.>
Go to step 7. Replace the ATF
temperature sen-
sor. <Ref. to 4AT-
64, Shift Sole-
noids, Duty Sole-
noids and ATF
Temperature Sen-
sor.>
Go to step 9. Go to step 8.
No