Subaru Legacy (2005 year). Service manual — part 613

5AT(diag)-43

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

Step

Check

Yes

No

1

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 connector and chassis ground.

Connector & terminal

(B54) No. 13 — Chassis ground:
(B54) No. 2 — Chassis ground:

Is the resistance more than 1
M

Ω?

Go to step 2.

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

2

CHECK ATF TEMPERATURE SENSOR.
1) Turn the ignition switch to OFF.
2) Connect the connectors to transmission
and TCM.
3) Turn the ignition switch to ON and start
engine.
4) Warm-up the transmission until the ATF
temperature exceeds 80

°C (176°F).

NOTE:

If the ambient temperature is below 0

°C (32°F),

drive the vehicle until the ATF reaches its oper-
ating temperature.

5) Disconnect the connector from transmis-
sion.
6) Measure the resistance between transmis-
sion connector terminals.

Connector & terminal

(T4) No. 5 — (T4) No. 12:

Is the resistance 500 — 1,200
Ω

Go to step 3.

Go to step 5.

3

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

Connector & terminal

(T4) No. 5 — (T4) No. 12:

Does the resistance value
increase while the ATF temper-
ature decreases?

Go to step 4.

Go to step 5.

4

CHECK INPUT SIGNAL FOR TCM USING
SUBARU SELECT MONITOR.
1) Connect the connector.
2) Turn the ignition switch to ON. (Engine
OFF)
3) Read the ATF temperature using Subaru
Select Monitor.

Does the ATF temperature
gradually decrease?

Even if the SPORT
indicator lights
blinks, the system
is in normal condi-
tion. A temporary
poor contact of
connector or har-
ness may be the
cause. Repair the
poor contact of
harness between
ATF temperature
sensor and trans-
mission connector.

Go to step 6.

5AT(diag)-44

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

5

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) Jack-up the vehicle and place it on rigid
racks.

NOTE:

Raise all wheels off floor.

5) Drain the ATF.

CAUTION:

Do not drain the ATF until it cools down.

6) Remove the oil pan, and disconnect the
connector from control valve body connector.
7) Measure the resistance between chassis
ground and control valve body connector.

Connector & terminal

(T10) No. 1 — Chassis ground:
(T10) No. 16 — Chassis ground:

Is the resistance more than 1
M

Ω?

Replace the con-
trol valve body.
<Ref. to 5AT-58,
Control Valve
Body.>

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

6

CHECK POOR CONTACT.

Is there poor contact in ATF
temperature sensor circuit 1?

Repair the poor
contact.

Replace the TCM.
<Ref. to 5AT-61,
Transmission Con-
trol Module
(TCM).>

Step

Check

Yes

No

5AT(diag)-45

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

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
• Does not shift to 5th
WIRING DIAGRAM:

AT-02074

1 2 3 4

10 11 12
19 20 21

13

5 6

14 15

7

8

9

16

17

18

22

23

24

AT1

1 2 3

1 2 3 4
5 6 7 8

B54

B55

1 2

7

8

9

5 6

3 4

10 11 12
19 20 21

13

14 15

16

17

18

22

23

24

B11

B12

1 2

5

6 7

8

13

14 15

16

9 10

11 12

3 4

17 18

19 20

B54

A:

B55

B:

A16

7

B11

T4

B12

T3

TCM

TURBINE SPEED SENSOR 1

B16

7

E

B:

A:

3

2

1

AT1

5AT(diag)-46

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

Step

Check

Yes

No

1

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.

Connector & terminal

(B55) No. 16 — (B12) No. 7:
(B54) No. 16 — (B11) No. 7:

Is the resistance less than 1
Ω?

Go to step 2.

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

2

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

Connector & terminal

(B55) No. 16 — Chassis ground:
(B54) No. 16 — Chassis ground:

Is the resistance more than 1
M

Ω?

Go to step 3.

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

3

CHECK TCM POWER SUPPLY OUTPUT.
1) Connect the TCM connector. (Transmission
connector is disconnected)
2) Turn the ignition switch to ON. (Engine
OFF)
3) Measure the voltage between TCM con-
nector and chassis ground.

Connector & terminal

(B54) No. 16 (+) — Chassis ground (

−

):

Is the voltage 10 — 13 V?

Go to step 4.

Go to step 5.

4

CHECK TURBINE SPEED SENSOR INPUT
CIRCUIT OF TCM.
Measure the voltage between TCM connector
terminals.

Connector & terminal

(B55) No. 16 (+) — (B54) No. 19 (

−

):

Is the voltage 4 — 6 V?

Go to step 6.

Go to step 5.

5

CHECK TCM I/O SIGNAL.
Check I/O signal of power supply, ground and
PVIGN power supply relay.
<Ref. to 5AT(diag)-13, ELECTRICAL SPECIFI-
CATION, Transmission Control Module (TCM)
I/O Signal.>

Is TCM I/O signal OK?

Replace the TCM.
<Ref. to 5AT-61,
Transmission Con-
trol Module
(TCM).>

Repair the open or
short circuit for
power supply and
ground. Perform
the diagnosis
according to DTC
for PVIGN power
supply relay.

6

CHECK HARNESS ASSEMBLY (TURBINE
SPEED SENSOR GROUND).
Check the installing condition of ground con-
necting harness of harness assembly (used for
both of turbine speed sensor 1, rear vehicle
speed sensor).

Is the ground connecting har-
ness connected to transmis-
sion body securely? And there
are no excessive damages on
harness and terminal?

Go to step 7.

When poor instal-
lation of ground
occurs, install it
securely. Replace
the transmission
assembly when
the harness or ter-
minal is damaged.
<Ref. to 5AT-38,
Automatic Trans-
mission Assem-
bly.>