Subaru Legacy IV (2008 year). Manual - part 652

CS-15

AT Shift Lock Control System

CONTROL SYSTEMS

2. BODY INTEGRATED UNIT POWER SUPPLY AND GROUND CIRCUIT

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

5

4

6 7

8

2

1

9

3

10

22

23

11 12 13 14 15

24 25

26 27

16 17 18

28 29

19 20

21

30

1 2

3 4

5 6

7 8

9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

24 25

26 27 28 29

30 31 32 33

34 35

B281

C:

B280

B:

i84

A:

OFF ACC

ACC

ON

B

IG

MAIN SBF

SBF-6

No.

 12

No.

 14

B281

C:

B280

B:

i84

A:

A1

C2

C8

C9

A21

B22

E

E

CS-00982

No.

 31

A24

SBF-8

No.

 7

C1

IGNITION SWITCH

B

A

TTER

Y

BODY INTEGRATED UNIT

CS-16

AT Shift Lock Control System

CONTROL SYSTEMS

Step

Check

Yes

No

1

CHECK DTC OF BODY INTEGRATED UNIT.
Check DTC of the body integrated unit.
<Ref. to LAN(diag)-12, OPERATION, Subaru 
Select Monitor.>

Is the DTC of power line dis-
played on body integrated unit?

Repair or replace it 
according to the 
DTC.

Go to step 2.

2

CHECK HARNESS CONNECTOR BETWEEN 
BODY INTEGRATED UNIT AND CHASSIS 
GROUND.
1) Turn the ignition switch to ON.
2) Measure the voltage between the body inte-
grated unit and chassis ground.

Connector & terminal

(B281) No. 2 (+) — Chassis ground (–):
(B281) No. 1 (+) — Chassis ground (–):
(i84) No. 1 (+) — Chassis ground (–):
(i84) No. 24 (+) — Chassis ground (–):

Is the voltage 9 — 16 V?

Go to step 3.

Repair harness for 
open circuit 
between the body 
integrated unit and 
the battery or a 
blown fuse.

3

CHECK HARNESS CONNECTOR BETWEEN 
BODY INTEGRATED UNIT AND CHASSIS 
GROUND.
1) Turn the ignition switch to OFF.
2) Measure the resistance of the harness 
between the body integrated unit and chassis 
ground.

Connector & terminal

(i84) No. 21 — Chassis ground:
(B280) No. 22 — Chassis ground:
(B281) No. 8 — Chassis ground:
(B281) No. 9 — Chassis ground:

Is the resistance less than 1 

:? Go to step 4.

Repair the open 
circuit of harness 
between the body 
integrated unit and 
chassis ground.

4

CHECK POOR CONTACT.

Is there poor contact in connec-
tor?

Repair the poor 
contact.

Check the body 
integrated unit.

CS-17

AT Shift Lock Control System

CONTROL SYSTEMS

3. SELECT LEVER CANNOT BE LOCKED OR RELEASED

B281

C:

F :

F :

MAIN SBF

SBF-2

No. 8

E

B281

C:

B280

B:

C

23

B6

B159

B116

4

3

3

2

B65

B116

1

2

3

4

B65

1 2

3 4

5 6 7 8 9 10

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

1 2

3 4

5 6 7 8 9

B159

C1

No.

 14

5

4

6 7

8

2

1

9

3

10

22

23

11 12 13 14 15

24 25

26 27

16 17 18

28 29

19 20

21

30

B280

B:

7.5A

3

B225

B225

4

C7

B350

4

3

5A

T

B30

B20

TCM

B54

B20

B21

5AT

16

10 11 12 13 14 15

25

24

30

9

8

7

17 18 19 20
28

21 22 23

29

32

31

1

2

3

4

5

6

27

26

33 34 35

B54

4A

T

A17

A18

B:

A:

B55

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

29 30 31

32 33

34 35

B55

A:

B:

E

C13

B116

1

2

CS-00965

13
14

15 16

17

27

24

25
26

20

21
22

23

29
30

31

28

32

35

33
34

37
38

39

36

40

8

9

10

11 12

1

2

5

3

4

7

6

19

18

F9
F5

: 4AT

: 5AT

BATTERY

STOP LIGHT SWITCH

FUSE & RELAY BOX

FUSE

(RELAY BLOCK)

: 4 SPEED AT

KEY WARNING SWITCH

BODY INTEGRATED UNIT

SHIFT LOCK SOLENOID

P RANGE SWITCH

: 5 SPEED AT

4AT

CS-18

AT Shift Lock Control System

CONTROL SYSTEMS

Step

Check

Yes

No

1

CHECK BODY INTEGRATED UNIT POWER 
SUPPLY AND GROUND CIRCUIT.
<Ref. to CS-15, BODY INTEGRATED UNIT 
POWER SUPPLY AND GROUND CIRCUIT, 
INSPECTION, AT Shift Lock Control System.>

Is there an abnormal condition? Follow the proce-

dures to perform 
inspection and 
repair.

Go to step 2.

2

CHECK CURRENT DATA.
1) Connect the Subaru Select Monitor.
2) Shift the select lever to the “P” range.
3) Turn the ignition switch to ON.
4) Display the current data display and display 
“P SW”. <Ref. to LAN(diag)-12, OPERATION, 
Subaru Select Monitor.>

Is the display “ON” in the P 
range and “OFF” in ranges 
other than P?

Go to step 3.

Go to step 8.

3

CHECK CURRENT DATA.
Display the current data display and display 
“Stop Light Switch”. <Ref. to LAN(diag)-12, 
OPERATION, Subaru Select Monitor.>

Is “ON” displayed when the 
brake pedal is depressed and 
“OFF” displayed when the 
brake pedal is released?

Go to step 4.

Go to step 11.

4

CHECK BODY INTEGRATED UNIT DTC.
Check the DTC of the body integrated unit when 
the brake pedal is pressed and when it is 
released.
(Hold each condition for 5 seconds or more.)

Is there a DTC of a current mal-
function?

Follow the DTC to 
perform inspection 
and repair.

Go to step 5.

5

CHECK CURRENT DATA.
Select the current data display and display 
“Shift Lock Solenoid”. <Ref. to LAN(diag)-12, 
OPERATION, Subaru Select Monitor.>

Is “ON” displayed when the 
brake pedal is depressed and 
“OFF” displayed when the 
brake pedal is released?

Go to step 6.

Replace the body 
integrated unit.

6

CHECK CURRENT DATA.
Select the current data display and display 
“Shift Position”. <Ref. to LAN(diag)-12, OPER-
ATION, Subaru Select Monitor.>

Is the display “7” in the P range 
and other than “7” in ranges 
other than P?

Go to step 7.

Check the follow-
ing items.
• Inhibitor switch
• Harness 
between inhibitor 
switch and TCM
• TCM input signal
• TCM CAN com-
munication
• Body integrated 
unit CAN receive

7

CHECK CURRENT DATA.
1) Select the current data display and display 
“Front Wheel Speed”. <Ref. to LAN(diag)-12, 
OPERATION, Subaru Select Monitor.>
2) Start the engine.
3) Raise vehicle speed gradually up to approx-
imately 20 km/h.

Is a figure equivalent to the 
speedometer being indicated?

Go to step 12.

Check the follow-
ing items.
• Wheel speed 
sensor
• VDC/ABS CAN 
communication
• Body integrated 
unit CAN receive
Replace the wheel 
speed sensor, 
VDC/ABS, or body 
integrated unit, or 
both.