Subaru Impreza 2003 Service Manual page 1740

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
AUTOMATIC TRANSMISSION (DIAGNOSTICS)
K: DTC 73 LOW CLUTCH TIMING SOLENOID
DIAGNOSIS:
The output signal circuit of low clutch timing solenoid is open or shorted.
TROUBLE SYMPTOM:
Excessive shift shock.
WIRING DIAGRAM:
B11
1 2 3 4 1 2
5 6 7 8 10 11 12
9 10 11 12 19 20 21
13 14 15 16
17 18 19 20
Step
1 CHECK HARNESS CONNECTOR BETWEEN
TCM AND TRANSMISSION.
1)Turn the ignition switch to OFF.
2)Disconnect the connector from TCM and
transmission.
3)Measure the resistance of harness between
TCM and transmission connector.
Connector & terminal
(B54) No. 15 — (B11) No. 3:
B54
3 4 5 6 7 8 9
13 14 15 16 17 18
22 23 24
B54 TCM
B11
T4
AT 9
TRANSMISSION
Check
Is the resistance less than 1
Ω?
4AT-70
Yes
Go to step 2. Repair the open
circuit in harness
between TCM and
transmission con-
nector.
AT-00585
No