Subaru Legacy 2004 Service Manual page 2509

Diagnostic Procedure with Diagnostic Trouble Code (DTC)
AUTOMATIC TRANSMISSION (DIAGNOSTICS)
Step
1 CHECK DTC.
2 CHECK BODY INTEGRATED UNIT.
1) Turn the ignition switch to OFF.
2) Connect the Subaru Select Monitor to data
link connector.
3) Turn the ignition switch to ON. (engine
OFF)
4) Turn the Subaru Select Monitor switch to
ON.
5) Depress the brake pedal.
6) Read the data of brake pedal switch using
Subaru Select Monitor. <Ref. to LAN(diag)-14,
OPERATION, Subaru Select Monitor.>
3 CHECK TCM.
Read the data of brake pedal switch using
Subaru Select Monitor. <Ref. to 5AT(diag)-16,
OPERATION, Subaru Select Monitor.>
4 CHECK BODY INTEGRATED UNIT INPUT
SIGNAL.
1) Disconnect the connector from body inte-
grated unit.
2) Depress the brake pedal.
3) Measure the voltage between body inte-
grated unit connector and chassis ground.
Connector & terminal
(B281) No. 23 (+) — Chassis ground (
5 CHECK HARNESS CONNECTOR BETWEEN
BODY INTEGRATED UNIT AND STOP LIGHT
SWITCH.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from stop light
switch.
3) Measure the resistance of harness
between body integrated unit and stop light
switch.
Connector & terminal
(B281) No. 23 — (B64) No. 2:
6 CHECK HARNESS CONNECTOR BETWEEN
BODY INTEGRATED UNIT AND STOP LIGHT
SWITCH.
Measure the resistance of harness between
body integrated unit connector and stop light
switch.
Connector & terminal
(B281) No. 23 — Chassis ground:
7 CHECK POOR CONTACT.
Check
Is any of following DTC dis-
played?
' AT CAN Communication Cir-
cuit
' Output Speed Sensor Circuit
' AT Vehicle Speed Sensor
Circuit Malfunction (Rear
Wheel)
Is the ON displayed?
Is the ON displayed?
Is the voltage more than 10 V? Go to step 7.
$
):
Is the resistance less than 1
"?
Is the resistance more than 1
M"?
Is there poor contact in input
signal of brake switch?
5AT(diag)-50
Yes
Perform the diag- Go to step 2.
nosis according to
DTC.
Go to step 3. Go to step 4.
A temporary poor Replace the TCM
contact of connec- <Ref. to 5AT-61,
tor or harness may Transmission Con-
be the cause. trol Module
Check the poor (TCM).>
contact.
Go to step 5.
Go to step 6. Repair the open
circuit of harness
between the body
integrated unit and
stop light switch.
Go to step 7. Repair the short
circuit of harness
between the body
integrated unit and
stop light switch.
Repair the poor Check the body
contact. integrated unit.
No