Subaru Legacy IV (2008 year). Service manual — part 767

5AT(diag)-83

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

AB:DTC P0817 STARTER DISABLE CIRCUIT

DTC DETECTING CONDITION:
Open or short in P/N signal output circuit
TROUBLE SYMPTOM:
• Engine can be started on other than “P” or “N” range
• Engine can not be started on “P” or “N” range.
WIRING DIAGRAM:

AT-04364

B136

B55

31

11

ECM

TCM

B136

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

B55

5

6

7

2

1

3

4

29

10 11 12 13 14 15

25

24

16

30

9

8

17 18 19

20
28

21 22 23

32

31

26 27

33

34 35

5AT(diag)-84

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

Step

Check

Yes

No

1

CHECK DTC OF TCM.

Is DTC of Transmission Range
Sensor Circuit (PRNDL Input)
detected?

Perform the diag-
nosis according to
DTC.

Go to step 2.

2

CHECK ECM.

Is the communication between
Subaru Select Monitor and
ECM normal?

Go to step 3.

Perform the diag-
nosis according to
DTC concerning
ECM.

3

CHECK FUSE (NO. 32).
1) Turn the ignition switch to OFF.
2) Remove the fuse.

Is the fuse (No. 32) blown out? Replace the fuse

(No. 32). If the
replaced fuse (No.
32) has blown out
easily, repair short
circuit of harness
between fuse (No.
32) and TCM.

Go to step 4.

4

CHECK HARNESS CONNECTOR BETWEEN
TCM AND ECM.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from TCM and
transmission.
3) Measure the resistance of harness between
TCM connector and transmission connector.

Connector & terminal

(B55) No. 11 — (B136) No. 31

Is the resistance less than 1

:? Go to step 5.

Repair the open
circuit of harness
between TCM and
transmission con-
nector, or poor
contact of connec-
tor.

5

CHECK HARNESS CONNECTOR BETWEEN
TCM AND ECM.
Measure the resistance of harness between
TCM connector and chassis ground.

Connector & terminal

(B55) No. 11 — Chassis ground:

Is the resistance 1 M

: or

more?

Go to step 6.

Repair the short
circuit of harness
between transmis-
sion connector and
chassis ground.

6

CHECK TCM OUTPUT SIGNAL.
1) Connect the TCM and ECM connector.
2) Turn the ignition switch to ON. (engine OFF)
3) Shift the select lever to “P” range.
4) Measure the voltage between TCM connec-
tor and chassis ground.

Connector & terminal

(B55) No. 11 (+) — Chassis ground (–):

Is the voltage 1 V or less?

Go to step 7.

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

7

CHECK TCM OUTPUT SIGNAL.
1) Shift the select lever to “D” range.
2) Measure the voltage between TCM connec-
tor and chassis ground.

Connector & terminal

(B55) No. 11 (+) — Chassis ground (–):

Is the voltage 8 V or more?

Go to step 8.

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

8

CHECK POOR CONTACT.

Is there any open or poor con-
tact of connector (loosing termi-
nal, entering foreign matter,
damaging connector body)?

Repair the poor
contact.

Check the neutral
switch of ECM.

5AT(diag)-85

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

AC:DTC P0957 BACKUP LIGHT RELAY CIRCUIT LOW

DTC DETECTING CONDITION:
Output circuit of the back-up light relay is open or shorted
TROUBLE SYMPTOM:
Back-up light does not illuminate in “R” range.
WIRING DIAGRAM:

13

B55

B226

TCM

IG2 RELAY

No.1

8

E

1

3

2

4

B226

B55

5

6

7

2

1

3

4

29

10 11 12 13 14 15

25

24

16

30

9

8

17 18 19

20
28

21 22 23

32

31

26 27

33

34 35

10
11

6

5

1

4

2

3

8 9

7

MAIN SBF

SBF-8

B

A

TTER

Y

BACK-UP LIGHT RELAY

BACK-UP LIGHT SYSTEM

AT-04365

5AT(diag)-86

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

Step

Check

Yes

No

1

CHECK DTC OF TCM.

Is DTC of Transmission Range
Sensor Circuit (PRNDL Input)
detected?

Perform the diag-
nosis according to
DTC.

Go to step 2.

2

CHECK HARNESS CONNECTOR BETWEEN
TCM AND BACK-UP LIGHT RELAY.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from TCM and
back-up light relay.
3) Measure the resistance of harness between
TCM connector and back-up light relay connec-
tor.

Connector & terminal

(B55) No. 13 — (B226) No. 4:

Is the resistance less than 1

:? Go to step 3.

Repair the open
circuit of harness
between TCM and
transmission con-
nector, or poor
contact of connec-
tor.

3

CHECK HARNESS CONNECTOR BETWEEN
TCM AND TRANSMISSION.
Measure the resistance of harness between
TCM connector and chassis ground.

Connector & terminal

(B55) No. 13 — Chassis ground:

Is the resistance 1 M

: or

more?

Go to step 4.

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

4

CHECK TCM OUTPUT SIGNAL.
1) Turn the ignition switch to ON. (engine OFF)
2) Shift the select lever to “P” range.
3) Measure the voltage between TCM connec-
tor and chassis ground.

Connector & terminal

(B55) No. 13 (+) — Chassis ground (–):

Is the voltage 8 V or more?

Go to step 5.

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

5

CHECK TCM OUTPUT SIGNAL.
1) Set the select lever to “R” range.
2) Measure the voltage between TCM connec-
tor and chassis ground.

Connector & terminal

(B55) No. 13 (+) — Chassis ground (–):

Is the voltage 1 V or less?

Go to step 6.

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

6

CHECK INPUT VOLTAGE FOR BACK-UP
LIGHT RELAY.
Measure the voltage between back-up light
relay and chassis ground.

Is the voltage 10 — 13 V?

Replace the back-
up light relay.

Check open or
short circuit of har-
ness between fuse
(No. 18) and back-
up light relay.