Subaru Legacy IV (2008 year). Manual - part 755

5AT(diag)-35

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

14.Diagnostic Procedure with Diagnostic Trouble Code (DTC)

A: DTC P0705 TRANSMISSION RANGE SENSOR CIRCUIT (PRNDL INPUT)

DTC DETECTING CONDITION:
The inhibitor switch is open or short.
TROUBLE SYMPTOM:
• Shift characteristics are erroneous.
• Shift indicator light does not match with select lever.
• Shift indicator light does not illuminate.
• N-D, N-R shock occur.

5AT(diag)-36

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

WIRING DIAGRAM:

AT-04894

3

21

22

i10

A26

A27

B20

B30

TCM

B55

i10

i84

B280

2

1

3 4

6 7 8 9 10

22

21

20

19

18

17

16

15

14

13

12

11

5

8

7

6

5

4

3

2

1

22 23

21

20

19

16

15

14

13

12

11

10

9

34 35

33

32

17
30

18
31

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

30

18

29

28

27

26

25

24

A:

B:

i107

i106

1 2 3 4 5 6 7 8 9 10

11 12 13 14 15 16 17 18 19 20

1

*

2

*

1

*

2

*

1 2 3 4

MAIN  SBF

SBF-6

No.

 5

E

B365

A:

B54

B:

B21

B20

T14

1

2

3

4

A11

A10

A9

A

8

6

2

3

5

T3

B12

B54

A:

B:

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

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

T14

1

3

4 5 6

2

B12

8

7

6

5

4

3

2

1

T24

i84

A:

B280

B:

B365

 :

 :

1

*

2

*

 :

*

 :

WN

 :

ON

WN

WN

ON

i107

i106

*

*

*

*

ON

WN

WN

ON

ON

I / F

IGNITION

SWITCH

B

A

TTER

Y

COMBINATION
METER

MICRO COMPUTER

DRIVE

CIRCUIT

CAN TRANSCEIVER  &  RECEIVER

CAN

JOINT

CONNECTOR

CAN
JOINT
CONNECTOR

CAN
JOINT
CONNECTOR

BODY

INTEGRATED UNIT

LCD FULL DOT

INHIBITOR SWITCH

CONTROL VALVE BODY

WITH NAVIGATION

WITHOUT NAVIGATION

TERMINAL No. OPTIONAL ARRANGEMENT
AMONG 1, 2, 3, 11, 12 AND 13

TERMINAL No. OPTIONAL ARRANGEMENT

TERMINAL No. OPTIONAL ARRANGEMENT
AMONG 8, 9, 10, 18, 19 AND 20

5AT(diag)-37

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

Step

Check

Yes

No

1

CHECK DTC OF TCM.

Is DTC of AT CAN communica-
tion circuit displayed?

Perform the diag-
nosis according to 
DTC.

Go to step 2.

2

CHECK INHIBITOR SWITCH.
1) Shift the select lever to “P” range.
2) Check input signal of inhibitor SW 1 — 4 
monitor using Subaru Select Monitor.

Is all displayed High?

Go to step 4.

Go to step 3.

3

CHECK HARNESS CONNECTOR BETWEEN 
TCM AND TRANSMISSION.
1) Turn the ignition switch to OFF.
2) Disconnect the connectors from TCM and 
transmission.
3) Measure the resistance between TCM con-
nector and chassis ground about the item which 
indicated Low on step 2.

Connector & terminal

(B54) No. 8 — Chassis ground:
(B54) No. 9 — Chassis ground:
(B54) No. 10 — Chassis ground:
(B54) No. 11 — Chassis ground:

Is the resistance 1 M

: or 

more?

Go to step 6.

Repair the short 
circuit of harness 
between TCM con-
nector and chassis 
ground.

4

CHECK INHIBITOR SWITCH.
1) Shift the select lever to “D” range.
2) Check input signal of inhibitor SW 1 — 4 
monitor using Subaru Select Monitor.

Is all displayed Low?

Go to step 6.

Go to step 5.

5

CHECK HARNESS CONNECTOR BETWEEN 
TCM AND TRANSMISSION.
1) Turn the ignition switch to OFF.
2) Disconnect the connectors from TCM and 
transmission.
3) Measure the resistance of harness between 
TCM and transmission connector about the 
item which indicated High on step 4.

Connector & terminal

(B54) No. 8 — (B12) No. 4:
(B54) No. 9 — (B12) No. 3:
(B54) No. 10 — (B12) No. 2:
(B54) No. 11 — (B12) No. 1:

Is the resistance less than 1 

:? Go to step 6.

Repair the open 
circuit of harness 
between TCM con-
nector and trans-
mission connector.

6

CHECK INPUT SIGNAL FOR TCM USING 
CIRCUIT TESTER.
1) Turn the ignition switch to OFF.
2) Disconnect the transmission connector 
(B12).
3) Connect the TCM connector.
4) Turn the ignition switch to ON.
5) Measure the voltage between TCM termi-
nals.

Connector & terminal

(B54) No. 8 (+) — (B55) No. 23 (–):
(B54) No. 9 (+) — (B55) No. 23 (–):
(B54) No. 10 (+) — (B55) No. 23 (–):
(B54) No. 11 (+) — (B55) No. 23 (–):

Is the voltage of inhibitor SW 1 — 
4 between 4 — 6 V?

Go to step 8.

Go to step 7.

7

CHECK TCM I/O SIGNAL.
Check the power supply and ground I/O signals.
<Ref. to 5AT(diag)-14, ELECTRICAL SPECIFI-
CATION, Transmission Control Module (TCM) I/
O Signal.>

Is TCM I/O signal OK?

Replace the TCM. 
<Ref. to 5AT-60, 
Transmission Con-
trol Module 
(TCM).>

Repair the open or 
short circuit for 
power supply and 
ground.

5AT(diag)-38

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

8

CHECK HARNESS CONNECTOR BETWEEN 
TRANSMISSION AND CONTROL VALVE 
BODY.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from transmis-
sion.
3) Remove the transmission connector from 
bracket.
4) Lift up the vehicle.

NOTE:
Raise all wheels off the floor.
5) Drain the ATF.

CAUTION:
Do not drain ATF until it cools down.
6) Remove the oil pan, and disconnect the 
connector from control valve body connector.
7) Measure the resistance between transmis-
sion connector and control valve body connec-
tor.

Connector & terminal

(T3) No. 4 — (T14) No. 2:
(T3) No. 3 — (T14) No. 3:
(T3) No. 2 — (T14) No. 5:
(T3) No. 1 — (T14) No. 6:

Is the resistance less than 1 

:? Go to step 9.

Repair the open 
circuit of harness 
between control 
valve body con-
nector and trans-
mission connector.

9

CHECK HARNESS CONNECTOR BETWEEN 
TRANSMISSION AND CONTROL VALVE 
BODY.
Measure the resistance between transmission 
ground and control valve body connector.

Connector & terminal

(T14) No. 2 — Transmission ground:
(T14) No. 3 — Transmission ground:
(T14) No. 5 — Transmission ground:
(T14) No. 6 — Transmission ground:

Is the resistance 1 M

: or 

more?

Go to step 10.

Repair the short 
circuit of harness 
between control 
valve body con-
nector and trans-
mission connector.

10

CHECK POOR CONTACT.

Is there any poor contact in 
inhibitor SW 1 — 4 monitor cir-
cuit?

Repair the poor 
contact.

Replace the con-
trol valve body. 
<Ref. to 5AT-57, 
Control Valve 
Body.>

Step

Check

Yes

No