5AT(diag)-47
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
AUTOMATIC TRANSMISSION (DIAGNOSTICS)
Step
Check
Yes
No
1
CHECK DTC.
Is any of following DTC dis-
played? / AT CAN Communica-
tion Circuit / Output Speed
Sensor Circuit / AT Vehicle
Speed Sensor Circuit Malfunc-
tion (Rear Wheel)
Perform the diag-
nosis according to
DTC.
Go to step 2.
2
CHECK FUSE (RELAY BLOCK).
Remove the fuse (7.5A) in the relay block.
Is the fuse (7.5A) blown out?
Replace the fuse
(7.5A). If the
replaced fuse
(7.5A) has blown
out easily, repair
short circuit of har-
ness between fuse
(7.5A) and body
integrated unit.
Go to step 3.
3
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 "Stop Light Switch" using
Subaru Select Monitor. <Ref. to LAN(diag)-12,
OPERATION, Subaru Select Monitor.>
Is ON displayed?
Go to step 4.
Go to step 5.
4
CHECK TCM.
Read the data of "Stop Light Switch" using Sub-
aru Select Monitor. <Ref. to 5AT(diag)-18,
OPERATION, Subaru Select Monitor.>
Is ON displayed?
A temporary poor
contact of connector
or harness may be
the cause. Check
the poor contact.
Replace the TCM.
<Ref. to 5AT-60,
Transmission Con-
trol Module
(TCM).>
5
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 (–):
Is the voltage 10 V or more?
Go to step 8.
Go to step 6.
6
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 — (B65) No. 3:
Is the resistance less than 1
:? Go to step 7.
Repair the open
circuit of harness
between body inte-
grated unit and
stop light switch.
7
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:
Is the resistance 1 M
: or
more?
Go to step 8.
Repair the short
circuit of harness
between body inte-
grated unit and
stop light switch.
8
CHECK POOR CONTACT.
Is there poor contact in input
signal of brake switch?
Repair the poor
contact.
Check the body
integrated unit.