Subaru Legacy IV (2008 year). Service manual — part 766

5AT(diag)-79

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

Z: DTC P0773 SHIFT SOLENOID “E” ELECTRICAL

DTC DETECTING CONDITION:
Output signal circuit of forward brake linear solenoid is open or shorted.
TROUBLE SYMPTOM:
Locked to 2nd, 3rd, 4th gear.
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

(B55) No. 22 — Chassis ground:
(B55) No. 23 — Chassis ground:
(B54) No. 19 — (B11) No. 13:

Is the resistance less than 1

:? Go to step 2.

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

2

CHECK HARNESS CONNECTOR BETWEEN
TCM AND BODY HARNESS.
Measure the resistance of harness between
TCM connector and body harness.

Connector & terminal

(B54) No. 19 — Chassis ground:

Is the resistance 1 M

: or

more?

Go to step 3.

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

AT-04363

A19

B11

T11

T4

13

7

CONTROL VALVE BODY

FORWARD BRAKE

LINEAR SOLENOID

B11

1

2

3 4

5

6 7

8

9

13

14 15

20

19

17

16

10

11 12

18

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

1 2 3 4
5 6 7 8

T11

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

TCM

B54

A:

B55

B:

B22

B23

E

B54

A:

B55

B:

5AT(diag)-80

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

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

Connector & terminal

(T4) No. 13 — (T11) No. 7:

Is the resistance less than 1

:? Go to step 4.

Repair the open
circuit of harness
between transmis-
sion connector and
control valve body
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 — Transmission ground:

Is the resistance 1 M

: or

more?

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

Go to step 5.

5

CHECK FORWARD BRAKE LINEAR SOLE-
NOID.
Measure the resistance of harness connector
between control valve body connector and
transmission ground.

Connector & terminal

(T11) No. 7 — Transmission ground:

Is the resistance 5 — 17

:?

Go to step 6.

Replace the con-
trol valve body.
<Ref. to 5AT-57,
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, damag-
ing 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 check
that there is no faulty.

Is DTC displayed?

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

Temporary poor
contact occurs.
Recheck that the
harness connector
has no faulty.

Step

Check

Yes

No

5AT(diag)-81

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

AA:DTC P0801 REVERSE INHIBIT CONTROL CIRCUIT

DTC DETECTING CONDITION:
Shift lock solenoid malfunction, open or short reverse inhibitor control circuit
TROUBLE SYMPTOM:
• Gear is shifted from “N” range to “R” range during driving at 20 km/h (12 MPH) or more.
• Gear can not be shifted from “N” range to “R” range though the vehicle is parked.
WIRING DIAGRAM:

Step

Check

Yes

No

1

CHECK SHIFT LOCK SOLENOID.
1) Start the integrated unit by force, and check
the operation of shift lock solenoid. <Ref. to
LAN(diag)-12, READ DIAGNOSTIC TROUBLE
CODE (DTC), OPERATION, Subaru Select
Monitor.>
2) Operate AT select lever without depressing
the brake pedal.

Does the AT select lever oper-
ate?

Go to step 2.

Go to step 3.

2

CHECK OUTPUT SIGNAL OF INTEGRATED
UNIT.
1) Display the following items using Subaru
Select Monitor.
• Key-lock warning SW
• Shift Position
• P SW
• Stop Light Switch
2) Step on the brake and shift the AT select
lever to “P” range.

Do the units of measure of
items displayed change?

Go to step 3.

Check the circuits
of the items whose
values do not
change.

3

CHECK HARNESS CONNECTOR BETWEEN
BODY INTEGRATED UNIT AND SHIFT LOCK
SOLENOID.
Measure the harness resistance between the
body integrated unit and chassis ground.

Connector & terminal

(B280) No. 6 — Chassis ground:

Is the resistance 1 M

: or

more?

Go to step 4.

Repair the short
circuit of harness
between body inte-
grated unit and
shift lock solenoid
connector.

6

E

B116

B116

3
4

B280

B280

1 2

3 4 5

6 7 8 9 10 11 12

5

4

6 7

8

2

1

9

3

10

22

23

11 12 13 14 15

24 25

26 27

16 17 18

28 29

19 20

21

30

AT-04340

BODY INTEGRATED UNIT

SHIFT LOCK
SOLENOID

5AT(diag)-82

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

4

CHECK HARNESS BETWEEN SHIFT LOCK
SOLENOID AND CHASSIS GROUND TERMI-
NAL.
Measure the resistance of harness between
shift lock solenoid and chassis ground.

Connector & terminal

(B116) No. 4 — Chassis ground:

Is the resistance less than 1

:? Go to step 5.

Repair the open
circuit of harness
between chassis
ground and shift
lock solenoid con-
nector.

5

CHECK SHIFT LOCK SOLENOID.
Measure the resistance of shift lock solenoid
terminals.

Connector & terminal

(B116) No. 3 — No. 4:

Is the resistance 7 — 21

:?

Go to step 6.

Replace the shift
lock solenoid.

6

CHECK OUTPUT SIGNAL OF BODY INTE-
GRATED UNIT.
1) Connect all connectors.
2) Turn the ignition switch to ON.
3) With the brake pedal depressed, shift the AT
select lever to “D” range.
4) Measure the voltage between body inte-
grated unit and chassis ground.

Connector & terminal

(B280) No. 6 (+) — Chassis ground (–):

Is the voltage 10.5 V or more?

Go to step 7.

Go to step 8.

7

CHECK OUTPUT SIGNAL OF BODY INTE-
GRATED UNIT.
1) Lift up the vehicle.

NOTE:
Raise all wheels off the floor.
2) Start the engine.
3) Shift the AT select lever to “D” range and
slowly increase vehicle speed to exceed 20 km/
h (12 MPH).

NOTE:
The speed difference between front and rear
wheels may illuminate the ABS warning light,
but this does not indicate a malfunction. When
AT control diagnosis is finished, perform the
ABS or VDC clear memory of on-board diag-
nostics system. <Ref. to ABS(diag)-20, Clear
Memory Mode.> <Ref. to VDC(diag)-23, Clear
Memory Mode.>
4) Measure the voltage between body inte-
grated unit and chassis ground.

Connector & terminal

(B280) No. 6 (+) — Chassis ground (–):

Is the voltage less than 1 V?

Even if the AT OIL
TEMP light illumi-
nates, the circuit is
in normal condi-
tion. A temporary
poor contact of
connector or har-
ness may be the
cause. Repair the
harness or con-
nector in the
reverse inhibitor
control circuit.

Go to step 8.

8

CHECK POOR CONTACT.

Is there poor contact in the
reverse inhibitor control circuit?

Repair the poor
contact.

Replace the body
integrated unit.
<Ref. to SL-56,
Body Integrated
Unit.>

Step

Check

Yes

No