Subaru Legacy (2005 year). Manual — part 617

5AT(diag)-59

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

2

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

Connector & terminal

(B54) No. 23 — Chassis ground:

Is the resistance more than 1
M

Ω?

Go to step 3.

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

3

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 ATF until it cools down.

6) Remove the oil pan, and disconnect the
control valve body connector.
7) Measure the resistance between transmis-
sion connector and control valve body connec-
tor.

Connector & terminal

(T4) No. 20 — (T11) No. 6:

Is the resistance less than 1
Ω?

Go to step 4.

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

4

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

Connector & terminal

(T11) No. 6 — Chassis ground:

Is the resistance more than 1
M

Ω?

Go to step 5.

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

5

CHECK LOCK-UP SOLENOID.
Measure the resistance between transmission
ground and control valve body connector.

Connector & terminal

(T11) No. 6 — Transmission ground:

Is the resistance 3 — 9

Ω

Go to step 6.

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

6

CHECK POOR CONTACT.
Check that there are no poor contact in TCM
connector, transmission connector and control
valve body connector.

Is there any loosing terminal,
entering foreign matter, dam-
aging connector body?

Repair the poor
contact.

Go to step 7.

7

CHECK AFTER REPAIR.
1) Perform the clear memory mode.
2) Drive for a while, read the DTC, and verify
that there is no faulty.

Is DTC displayed?

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

Temporary poor
contact or open
circuit occurs.
Recheck that the
harness connec-
tor has no faulty.

Step

Check

Yes

No

5AT(diag)-60

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

Q: DTC P0748 PRESSURE CONTROL SOLENOID “A” ELECTRICAL

DTC DETECTING CONDITION:
Output signal circuit of line pressure solenoid is open or shorted.
TROUBLE SYMPTOM:
Excessive shift shock
WIRING DIAGRAM:

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

(B54) No. 9 — (B11) No. 19:
(B54) No. 5 — Chassis ground:
(B54) No. 14 — Chassis ground:

Is the resistance less than 1
Ω?

Go to step 2.

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

AT-03182

B54

E

5

14

9

B11

TCM

B54

B11

1 2

5

6 7

8

13

14 15

16

9 10

11 12

3 4

17 18

19 20

TRANSMISSION

1 2

7

8

9

5 6

3 4

10 11 12
19 20 21

13

14 15

16

17

18

22

23

24

T4

7

T11

1 2
5

8

6

9 10 11

3 4

12

T11

7

19

5AT(diag)-61

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

2

CHECK HARNESS CONNECTOR BETWEEN
TCM AND CHASSIS GROUND.
Measure the resistance between TCM connec-
tor and chassis ground.

Connector & terminal

(B54) No. 9 — Chassis ground:

Is the resistance more than 1
M

Ω?

Go to step 3.

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

3

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
control valve body connector.
7) Measure the resistance between transmis-
sion connector and control valve body connec-
tor.

Connector & terminal

(T4) No. 19 — (T11) No. 7:

Is the resistance less than 1
Ω?

Go to step 4.

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

4

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

Connector & terminal

(T11) No. 7 — Chassis ground:

Is the resistance more than 1
M

Ω?

Go to step 5.

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

5

CHECK LINE PRESSURE SOLENOID.
Measure the resistance between transmission
ground and control valve body connector.

Connector & terminal

(T11) No. 7 — Transmission ground:

Is the resistance 3 — 9

Ω

Go to step 6.

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

6

CHECK POOR CONTACT.
Check that there are no poor contact in TCM
connector, transmission connector and control
valve body connector.

Is there any loosing terminal,
entering foreign matter, dam-
aging connector body?

Repair the poor
contact.

Go to step 7.

7

CHECK AFTER REPAIR.
1) Perform the clear memory mode.
2) Drive for a while, read the DTC, and verify
that there is no faulty.

Is DTC displayed?

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

Temporary poor
contact or open
circuit occurs.
Recheck that the
harness connec-
tor has no faulty.

Step

Check

Yes

No

5AT(diag)-62

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

R: DTC P0751 SHIFT SOLENOID “A” PERFORMANCE OR STUCK OFF

DTC DETECTING CONDITION:
Output signal of front brake solenoid does not match with oil pressure.
TROUBLE SYMPTOM:
Locked to 4th or 5th gear.
WIRING DIAGRAM:

AT-03183

B54

B55

A:

B:

A:

A24

B11

TCM

B54

B11

1 2

5

6 7

8

13

14 15

16

9 10

11 12

3 4

17 18

19 20

TRANSMISSION

1 2

7

8

9

5 6

3 4

10 11 12
19 20 21

13

14 15

16

17

18

22

23

24

T4

T11

1 2
5

8

6

9 10 11

3 4

12

T11

7

17

E

A5

A14

B17

3

9

11

T10

1 2 3 4

10 11 12
19 20 21

13

5 6

14 15

7

8

9

16

17

18

22

23

24

B55

B:

1 2 3

6

8 9 10 11 12 13 14

4 5

15 16

T10

7