Subaru Legacy 2005 Service Manual page 2214

Diagnostic Procedure with Diagnostic Trouble Code (DTC)
AUTOMATIC TRANSMISSION (DIAGNOSTICS)
Step
1 CHECK HARNESS CONNECTOR BETWEEN
TCM AND ATF TEMPERATURE SENSOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from transmis-
sion and TCM.
3) Measure the resistance of harness
between TCM and transmission connector.
Connector & terminal
(B54) No. 21 — (B11) No. 11:
2 CHECK HARNESS CONNECTOR BETWEEN
TCM AND ATF TEMPERATURE SENSOR.
Measure the resistance of harness between
TCM and transmission connector.
Connector & terminal
(B54) No. 9 — (B11) No. 15:
3 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 the ATF
temperature exceeds 80°C (176°F).
NOTE:
If the ambient temperature is below 0°C (32°F),
drive the vehicle until the ATF reaches its oper-
ating temperature.
5) Disconnect the connector from transmis-
sion.
6) Measure the resistance between transmis-
sion connector terminals.
Connector & terminal
(T4) No. 11 — No. 15:
4 CHECK ATF TEMPERATURE SENSOR.
Measure the resistance between transmission
connector terminals.
Connector & terminal
(T4) No. 11 — No. 15:
5 CHECK INPUT SIGNAL FOR TCM USING
SUBARU SELECT MONITOR.
1) Connect the connector to transmission.
2) Connect the Subaru Select Monitor to data
link connector.
3) Turn the ignition switch to ON (engine
OFF).
4) Read the data of ATF temperature using
Subaru Select Monitor.
6 CHECK POOR CONTACT.
Check
Is the resistance less than 1
Ω?
Is the resistance less than 1
Ω?
Is the resistance 300 — 800
Ω?
Does the resistance value
increase while the ATF temper-
ature decreases?
Does the ATF temperature
gradually decrease?
Is there poor contact in ATF
temperature sensor circuit?
4AT(diag)-42
Yes
Go to step 2. Repair the open
circuit of harness
between TCM and
transmission con-
nector.
Go to step 3. Repair the open
circuit of harness
between TCM and
transmission con-
nector.
Go to step 4. Go to step 7.
Go to step 5. Go to step 7.
Even if the SPORT Go to step 6.
indicator light is
blinking, the cir-
cuit has returned
to normal condi-
tion at this time. A
temporary poor
contact of connec-
tor or harness may
be the cause.
Repair the har-
ness or contact in
the ATF tempera-
ture sensor and
transmission con-
nector.
Repair the poor Replace the TCM.
contact. <Ref. to 4AT-66,
Transmission Con-
trol Module
(TCM).>
No