Subaru Legacy IV (2008 year). Manual - part 716

4AT(diag)-85

Diagnostic Procedure without Diagnostic Trouble Code (DTC)

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

11

CHECK POOR CONTACT.

Is there poor contact in FWD 
switch circuit?

Repair the poor 
contact.

Replace the TCM. 
<Ref. to 4AT-61, 
Transmission Con-
trol Module 
(TCM).>

Step

Check

Yes

No

4AT(diag)-86

Diagnostic Procedure without Diagnostic Trouble Code (DTC)

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

B: CHECK SPORT SHIFT SWITCH

DIAGNOSIS:
Input signal circuit of SPORT/manual mode switch is open or shorted.
TROUBLE SYMPTOM:
Does not shift on manual mode.
WIRING DIAGRAM:

AT-04343

1

*

1

*

2

*

1

*

2

*

2

*

B281

C:

B280

B:

B20

B30

C25

C15

18

17

B116

TCM

B54

10

11

6

7

B280

B281

8

7

6

5

4

3

2

1

22

23

21

20

19

16

15

14

13

12

11

10

9

17

30

18

29

28

27

26

25

24

8

7

6

5

4

3

2

1

22 23

21

20

19

16

15

14

13

12

11

10

9

17 18

28

27

26

25

24

B116

E

B:

C:

B365

B365

B54

5

6

7 8

2

1

9

4

3

10

24

22 23

25

11 12 13 14 15

26 27

28

16

17 18 19 20 21

33 34

29

32

30

31

35

8

9

C26

UP

DO

WN

1 2

3 4 5

6 7 8 9 10 11 12

9

8

7

6

5

4

3

2

1

10

11 12 13 14 15 16 17 18 19 20

BODY INTEGRATED UNIT

AT SELECT LEVER

JOINT

CONNECTOR

SPORT/
MANUAL 
MODE SWITCH

: TERMINAL No. OPTIONAL  
  ARRANGEMENT 
  AMONG 1, 2, 3, 11, 12  AND 13
: TERMINAL No. OPTIONAL 
  ARRANGEMENT 
  AMONG 8, 9, 10, 18, 19  AND 20

4AT(diag)-87

Diagnostic Procedure without Diagnostic Trouble Code (DTC)

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

Step

Check

Yes

No

1

CHECK SPORT SHIFT SWITCH.
1) Move the AT select lever to SPORT mode.
2) Shift and hold the AT select lever to up side.
3) Read the “Up Switch” data of the TCM using 
the Subaru Select Monitor. <Ref. to 4AT(diag)-
17, READ CURRENT DATA, OPERATION, 
Subaru Select Monitor.>

Is ON displayed?

Go to step 2.

Go to step 3.

2

CHECK SPORT SHIFT SWITCH.
1) Shift and hold the AT select lever to down 
side.
2) Read the “Down Switch” data of TCM using 
Subaru Select Monitor.

Is ON displayed?

Go to the proce-
dure “CHECK 
SPORT SHIFT 
INDICATOR”. 
<Ref. to 4AT(diag)-
90, CHECK 
SPORT SHIFT 
INDICATOR, Diag-
nostic Procedure 
without Diagnostic 
Trouble Code 
(DTC).>

Go to step 12.

3

CHECK BODY INTEGRATED UNIT.
1) Turn the ignition switch to ON.
2) Shift and hold the AT select lever to up side.
3) Read the “TIP UP SW input” data of body 
integrated unit 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 BODY INTEGRATED UNIT.
Check DTC of body integrated unit. <Ref. to 
LAN(diag)-12, OPERATION, Subaru Select 
Monitor.>

Is DTC of CAN communication 
displayed?

Perform the diag-
nosis according to 
DTC.

Inspect the TCM.

5

CHECK GROUND CIRCUIT OF SPORT/MAN-
UAL MODE SWITCH.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from SPORT/
manual mode switch.
3) Measure the resistance of harness between 
SPORT/manual mode switch connector and 
chassis ground.

Connector & terminal

(B116) No. 6 — Chassis ground:

Is the resistance less than 1 

:? Go to step 6.

Repair the open 
circuit of harness 
between SPORT/
manual mode 
switch and chassis 
ground.

6

CHECK SPORT/MANUAL MODE SWITCH.
Measure the resistance between SPORT/man-
ual mode switch terminals.

Connector & terminal

(B116) No. 6 — No. 7:

Is the resistance 1 M

: or 

more?

Go to step 7.

Replace the guide 
plate assembly.

7

CHECK SPORT/MANUAL MODE SWITCH.
1) Shift and hold the AT select lever to up side.
2) Measure the resistance between SPORT/
manual mode switch terminals.

Connector & terminal

(B116) No. 6 — No. 7:

Is the resistance less than 1 

:? Go to step 8.

Replace the guide 
plate assembly.

4AT(diag)-88

Diagnostic Procedure without Diagnostic Trouble Code (DTC)

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

8

CHECK HARNESS CONNECTOR BETWEEN 
BODY INTEGRATED UNIT AND SPORT/
MANUAL MODE SWITCH.
1) Disconnect the connector from body inte-
grated unit.
2) Measure the resistance of harness between 
body integrated unit connector and SPORT/
manual mode switch connector.

Connector & terminal

(B116) No. 7 — (B281) No. 15:

Is the resistance less than 1 

:? Go to step 9.

Repair the open 
circuit of harness 
between the 
SPORT/manual 
mode switch con-
nector and body 
integrated unit con-
nector, or poor 
contact of connec-
tor.

9

CHECK HARNESS CONNECTOR BETWEEN 
BODY INTEGRATED UNIT AND SPORT/
MANUAL MODE SWITCH.
Measure the resistance of harness between 
SPORT/manual mode switch connector and 
chassis ground.

Connector & terminal

(B116) No. 7 — Chassis ground:

Is the resistance 1 M

: or 

more?

Go to step 10.

Repair the short 
circuit of harness 
between SPORT/
manual mode 
switch connector 
and body inte-
grated unit connec-
tor.

10

CHECK INPUT SIGNAL TO BODY INTE-
GRATED UNIT.
1) Connect all connectors.
2) Turn the ignition switch to ON (engine OFF).
3) Check the signal voltage for body integrated 
unit.

Connector & terminal

(B281) No. 15 (+) — Chassis ground (–):

Is the voltage 1.5 — 8 V?

Go to step 11.

Replace the body 
integrated unit.

11

CHECK INPUT SIGNAL TO BODY INTE-
GRATED UNIT.
1) Shift and hold the AT select lever to shift up 
side.
2) Check the signal voltage for body integrated 
unit.

Connector & terminal

(B281) No. 15 (+) — Chassis ground (–):

Is the voltage less than 1 V?

Go to step 21.

Replace the body 
integrated unit.

12

CHECK BODY INTEGRATED UNIT.
1) Turn the ignition switch to ON.
2) Shift and hold the AT select lever to down 
side.
3) Read the “TIP DOWN SW input” data of 
body integrated unit using Subaru Select Moni-
tor. <Ref. to LAN(diag)-12, OPERATION, Sub-
aru Select Monitor.>

Is ON displayed?

Go to step 13.

Go to step 14.

13

CHECK BODY INTEGRATED UNIT.
Check DTC of body integrated unit.

Is DTC of CAN communication 
displayed?

Perform the diag-
nosis according to 
DTC.

Inspect the TCM.

14

CHECK GROUND CIRCUIT OF SPORT/MAN-
UAL MODE SWITCH.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from SPORT/
manual mode switch.
3) Measure the resistance of harness between 
SPORT/manual mode switch connector and 
chassis ground.

Connector & terminal

(B116) No. 10 (+) — Chassis ground:

Is the resistance less than 1 

:? Go to step 15.

Repair the open 
circuit of harness 
between SPORT/
manual mode 
switch and chassis 
ground.

15

CHECK SPORT/MANUAL MODE SWITCH.
Measure the resistance between SPORT/man-
ual mode switch terminals.

Connector & terminal

(B116) No. 10 — No. 11:

Is the resistance 1 M

: or 

more?

Go to step 16.

Replace the guide 
plate assembly.

Step

Check

Yes

No