Subaru Legacy IV (2008 year). Service manual — part 705

4AT(diag)-41

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

7

CHECK HARNESS CONNECTOR BETWEEN
TRANSMISSION AND ATF TEMPERATURE
SENSOR.
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.
5) Drain the automatic transmission fluid.

CAUTION:
Do not drain ATF until it cools down.
6) Remove the oil pan, and disconnect the
control valve connector.
7) Measure the resistance of harness between
ATF temperature sensor and transmission con-
nector.

Connector & terminal

(T4) No. 11 — (AT2) No. 4:

Is the resistance less than 1

:? Go to step 8.

Repair the open
circuit of harness
between ATF tem-
perature sensor
and transmission
connector.

8

CHECK HARNESS CONNECTOR BETWEEN
TRANSMISSION AND ATF TEMPERATURE
SENSOR.
Measure the resistance of harness between
ATF temperature sensor and transmission con-
nector.

Connector & terminal

(T4) No. 15 — (AT2) No. 9:

Is the resistance less than 1

:? Go to step 9.

Repair the open
circuit of harness
between ATF tem-
perature sensor
and transmission
connector.

9

CHECK HARNESS CONNECTOR BETWEEN
TRANSMISSION AND ATF TEMPERATURE
SENSOR.
Measure the resistance of harness between
transmission connector and transmission
ground.

Connector & terminal

(T4) No. 11 — Transmission ground:

Is the resistance 1 M

: or

more?

Go to step 10.

Repair the short
circuit of harness
between ATF tem-
perature sensor
and transmission
connector.

10

CHECK HARNESS CONNECTOR BETWEEN
TRANSMISSION AND ATF TEMPERATURE
SENSOR.
Measure the resistance of harness between
transmission connector and transmission
ground.

Connector & terminal

(T4) No. 15 — Transmission ground:

Is the resistance 1 M

: or

more?

Replace the con-
trol valve body.
<Ref. to 4AT-56,
Control Valve
Body.>

Repair the short
circuit of harness
between ATF tem-
perature sensor
and transmission
connector.

Step

Check

Yes

No

4AT(diag)-42

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

C: DTC P0713 TRANSMISSION FLUID TEMPERATURE SENSOR CIRCUIT HIGH

INPUT

DTC DETECTING CONDITION:
Input signal circuit to ATF temperature sensor is shorted.
TROUBLE SYMPTOM:
Excessive shift shock
WIRING DIAGRAM:

Step

Check

Yes

No

1

CHECK HARNESS CONNECTOR BETWEEN
TCM AND ATF TEMPERATURE SENSOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from TCM.
3) Measure the resistance between TCM con-
nector terminals.

Connector & terminal

(B54) No. 23 — No. 12:

Is the resistance 500

: or

more?

Go to step 2.

Go to step 4.

2

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

Connector & terminal

(B54) No. 23 — Chassis ground:

Is the resistance 1 M

: or

more?

Go to step 3.

Go to step 4.

3

CHECK HARNESS.
Measure the resistance between TCM connec-
tor terminals while shaking the harness.

Connector & terminal

(B54) No. 23 — No. 12:

Does the resistance change?

Go to step 4.

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

4

CHECK HARNESS CONNECTOR BETWEEN
TCM AND ATF TEMPERATURE SENSOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from transmis-
sion.
3) Measure the resistance of harness between
TCM connector and chassis ground.

Connector & terminal

(B54) No. 23 — Chassis ground:

Is the resistance 1 M

: or

more?

Go to step 5.

Repair the short
circuit of harness
between TCM and
transmission har-
ness.

AT-04767

B11

1

2

3 4

5

6 7

8

9

13

14 15

20

19

17

16

10

11 12

18

23

12

15

11

9

4

B54

B11

AT2

T4

TCM

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

AT2

10

9

8

7

6

5

4

3

2

1

CONTROL VALVE BODY

ATF
TEMPERATURE
SENSOR

4AT(diag)-43

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

5

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

Connector & terminal

(B54) No. 12 — Chassis ground:

Is the resistance 1 M

: or

more?

Go to step 6.

Repair the short
circuit of harness
between TCM and
transmission har-
ness.

6

CHECK ATF TEMPERATURE SENSOR.
Measure the resistance between transmission
connector terminals.

Connector & terminal

(T4) No. 11 — No. 15:

Is the resistance 500

: or

more?

Even if the ATF
temperature warn-
ing light blinks, the
circuit is in normal
condition at this
time. A temporary
short circuit of con-
nector or harness
may be the cause.
Repair the harness
or connector.

Go to step 7.

7

CHECK TRANSMISSION HARNESS.
1) Lift up the vehicle.
2) Drain the automatic transmission fluid.

CAUTION:
Do not drain ATF until it cools down.
3) Remove the oil pan.
4) Disconnect the harness connector from
control valve.
5) Measure the resistance between ATF tem-
perature sensor connector terminals.
6) Measure the resistance between transmis-
sion connector and transmission ground.

Connector & terminal

(T4) No. 11 — Transmission ground:

Is the resistance 1 M

: or

more?

Go to step 8.

Replace the trans-
mission harness.

8

CHECK TRANSMISSION HARNESS.
Measure the resistance between transmission
connector and transmission ground.

Connector & terminal

(T4) No. 15 — Transmission ground:

Is the resistance 1 M

: or

more?

Go to step 9.

Replace the trans-
mission harness.

9

CHECK ATF TEMPERATURE SENSOR.
Measure the resistance between control valve
connector terminals.

Terminals

No. 4 — No. 9:

Is the resistance 500

: or

more?

Even if the ATF
temperature warn-
ing light blinks, the
circuit is in normal
condition at this
time. A temporary
short circuit of con-
nector or harness
may be the cause.
Repair the harness
or connector.

Replace the con-
trol valve body.
<Ref. to 4AT-56,
Control Valve
Body.>

Step

Check

Yes

No

4AT(diag)-44

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

D: DTC P0715 INPUT/TURBINE SPEED SENSOR CIRCUIT

DTC DETECTING CONDITION:
Input signal circuit of TCM is open or shorted.
TROUBLE SYMPTOM:
Excessive shift shock
WIRING DIAGRAM:

AT-04330

5

10

B11

T4

TCM

B54

1

B11

2

B53

B53

1 2 3 4 5 6 7 8 9 10

11 12 13 14 15 16 17 18 19 20

:

*

*

*

*

B54

1 2

5

6 7

8

13

14 15

16

9 10

11 12

3 4

17 18

19 20

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

JOINT
CONNECTOR

TORQUE

CONVERTER

TURBINE

SPEED SENSOR

TERMINAL No. OPTIONAL
ARRANGEMENT AMONG 2, 3 AND 13