Subaru 2002 IMPREZA Service Manual page 1690

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
AUTOMATIC TRANSMISSION (DIAGNOSTICS)
Step
9 CHECK INPUT SIGNAL FOR TCM USING
SUBARU SELECT MONITOR.
1)Connect the connectors to TCM and trans-
mission.
2)Connect the Subaru Select Monitor to data
link connector.
3)Lift-up or raise the vehicle and place safety
stands.
NOTE:
On AWD models, raise all wheels off floor.
4)Turn the ignition switch to ON and turn Sub-
aru Select Monitor switch to ON.
5)Start the engine.
6)Read the data of vehicle speed using Subaru
Select Monitor.
•Compare the speedometer with Subaru
Select Monitor indications.
•Vehicle speed is indicated in "km/h" or "MPH".
7)Slowly increase the vehicle speed to 60 km/h
or 37 MPH.
NOTE:
The speed difference between front and rear
wheels may light the ABS warning light, but this
indicates no malfunction. When AT control di-
agnosis is finished, perform the ABS memory
clearance procedure of on-board diagnostics
system. <Ref. to ABS-22, Clear Memory
Mode.>
10 CHECK INPUT SIGNAL FOR TCM USING
OSCILLOSCOPE.
1)Connect the connectors to TCM and trans-
mission.
2)Lift-up or raise the vehicle and place safety
stands.
NOTE:
On AWD models, raise all wheels off floor.
3)Set the oscilloscope to TCM connector termi-
nals.
Connector & terminal
Positive probe; (B55) No. 24
Earth lead; (B54) No. 19
4)Start the engine and set vehicle in 20 km/h
(12 MPH) condition.
NOTE:
The speed difference between front and rear
wheels may light the ABS warning light, but this
indicates no malfunction. When AT control di-
agnosis is finished, perform the ABS memory
clearance procedure of on-board diagnostics
system. <Ref. to ABS-22, Clear Memory
Mode.>
5)Measure the signal voltage indicated on
oscilloscope.
11 CHECK POOR CONTACT.
Check
Does the speedometer indica-
tion increase as the Subaru
Select Monitor data increases?
Is the signal voltage more than
AC 1 V?
Is there poor contact in rear
vehicle speed sensor circuit?
AT-104
Yes
Even if the Go to step 11.
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 TCM and trans-
mission.
Even if the Go to step 11.
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 TCM and trans-
mission.
Repair the poor Replace the TCM.
contact. <Ref. to AT-46,
Transmission Con-
trol Module
(TCM).>
No