Subaru Legacy (2005 year). Manual - part 633

5AT(diag)-123

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

AQ:DTC P1798 GEAR 1 ENGINE BRAKE

NOTE:
Refer to DTC P0773 for diagnostic procedure. <Ref. to 5AT(diag)-85, DTC P0773 SHIFT SOLENOID “E”
ELECTRICAL, Diagnostic Procedure with Diagnostic Trouble Code (DTC).>

15

CHECK INPUT VOLTAGE OF LATERAL G 
SENSOR.
1) Turn the ignition switch to OFF.
2) Remove the console box.
3) Remove the lateral G sensor from vehicle. 
(Do not disconnect connector.)
4) Turn the ignition switch to ON.
5) Measure the voltage between lateral G 
sensor connector terminals.

Connector & terminal

(B359) No. 1 (+) — No. 2 (

−

):

Is the voltage 4.75 — 5.25 V?

Go to step 16.

Repair the har-
ness connector 
between lateral G 
sensor and TCM.

16

CHECK OPEN CIRCUIT IN LATERAL G SEN-
SOR OUTPUT HARNESS AND GROUND 
HARNESS.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from TCM.
3) Measure the resistance between TCM con-
nector terminals.

Connector & terminal

(B55) No. 5 — No. 6:

Is the resistance 5.0 — 5.6 
k

Ω?

Go to step 17.

Repair the har-
ness connector 
between lateral G 
sensor and TCM.

17

CHECK LATERAL G SENSOR.
1) Connect the connector to lateral G sensor.
2) Connect the connector to the TCM.
3) Turn the ignition switch to ON.
4) Measure the voltage between lateral G 
sensor connector terminals.

Connector & terminal

(B359) No. 3 (+) — No. 2 (

−

):

Is the voltage between 2.3 and 
2.7 V when lateral G sensor is 
horizontal?

Go to step 18.

Replace the lat-
eral G sensor. 
<Ref. to 5AT-62, 
Lateral G Sensor.>

18

CHECK LATERAL G SENSOR.
Measure the voltage between lateral G sensor 
connector terminals.

Connector & terminal

(B359) No. 3 (+) — No. 2 (

−

):

Is the voltage between 3.3 — 
4.3 V when lateral G sensor is 
inclined to the right to 90

°?

Go to step 19.

Replace the lat-
eral G sensor. 
<Ref. to 5AT-62, 
Lateral G Sensor.>

19

CHECK LATERAL G SENSOR.
Measure the voltage between lateral G sensor 
connector terminals.

Connector & terminal

(B359) No. 3 (+) — No. 2 (

−

):

Is the voltage 0.7 — 1.7 V 
when lateral G sensor is 
inclined to the left to 90

°?

Go to step 20.

Replace the lat-
eral G sensor. 
<Ref. to 5AT-62, 
Lateral G Sensor.>

20

CHECK POOR CONTACT IN CONNECTOR.
Turn the ignition switch to OFF.

Is there poor contact in con-
nector between TCM and lat-
eral G sensor?

Repair the con-
nector.

Go to step 21.

21

CHECK ABSCM&H/U.
1) Connect all the connectors.
2) Perform the clear memory mode.
3) Perform the inspection mode.
4) Read the DTC.

Is the same DTC displayed?

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

Go to step 22.

22

CHECK OTHER DTC DETECTION.

Is any other DTC displayed?

Perform the diag-
nosis according to 
DTC.

Temporary poor 
contact occurs.

Step

Check

Yes

No

5AT(diag)-124

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

AR:DTC P1799 INTERLOCK

DTC DETECTING CONDITION:
Perform the interlock judgment when the oil pressure switch pattern detects the specified interlock patterns
other than shifting.
TROUBLE SYMPTOM:
Locked to 2nd, 4th or 5th gear depending on the vehicle condition at the time of diagnosis.

Step

Check

Yes

No

1

CHECK DTC OF TCM.

Is any of the DTC P0751, 
P0756, P0761, P0766, P0771 
displayed at the same time 
with P1799?

Perform the diag-
nosis according to 
DTC.

Go to step 2.

2

CHECK DTC P0756, P0766.

Perform the diagnosis accord-
ing to DTC P0756, P0766. Is 
any malfunction detected?

Perform the diag-
nosis according to 
DTC.

Go to step 3.

3

DRIVING CHECK.
1) Turn the ignition switch to OFF.
2) Perform the inspection mode.

Is DTC displayed?

Replace the trans-
mission assembly.

Temporary poor 
contact occurs. 
Check that the 
harness connec-
tor has no faulty.

5AT(diag)-125

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

AS:DTC P1817 SPORT MODE SWITCH CIRCUIT (MANUAL SWITCH)

DTC DETECTING CONDITION:
Input signal circuit of SPORT mode and manual mode switch is open or shorted.
TROUBLE SYMPTOM:
• Manual mode can not be set.
• “SPORT” light illuminates when shifting to “N” 

→ “D” range.

WIRING DIAGRAM:

i10

i77

i84

B280

B54

B116

B281

2

1

3 4

6 7 8 9 10

22

21

20

19

18

17

16

15

14

13

12

11

5

12

11

10

9

8

7

6

5

4

3

2

1

10

9

8

7

6

5

4

3

2

1

8

7

6

5

4

3

2

1

22 23

21

20

19

16

15

14

13

12

11

10

9

34 35

33

32

17
30

18
31

29

28

27

26

25

24

8

7

6

5

4

3

2

1

22

23

21

20

19

16

15

14

13

12

11

10

9

17

30

18

29

28

27

26

25

24

8

7

6

5

4

3

2

1

22 23

21

20

19

16

15

14

13

12

11

10

9

17 18

28

27

26

25

24

AT-03176

C26

B116

8

7

3

4

21

1

22

7

i10

i77

i84

A:

B280

B:

B281

C:

2

8

A26

A27

B20

B30

4

3

TCM

B54

SPORT

MAIN SBF

SBF-6

No.5

E

E

B

A

TTER

Y

IGNITION
SWITCH

COMBINATION
METER

JOINT
CONNECTOR

BODY INTEGRATED MODULE

SELECT
LEVER

SPORT MODE
AND MANUAL
MODE SWITCH

A: 

B: 

C: 

1 2

7

8

9

5 6

3 4

10 11 12
19 20 21

13

14 15

16

17

18

22

23

24

5AT(diag)-126

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

Step

Check

Yes

No

1

CHECK BODY INTEGRATED MODULE.
1) Connect the Subaru Select Monitor to data 
link connector.
2) Turn the ignition switch to ON. (engine 
OFF)
3) Read the DTC of body integrated module 
using Subaru Select Monitor. <Ref. to 
LAN(diag)-14, OPERATION, Subaru Select 
Monitor.>

Is DTC displayed?

Perform the diag-
nosis according to 
DTC.

Go to step 2.

2

CHECK BODY INTEGRATED MODULE IN-
PUT SIGNAL.
1) Shift the select lever to “P” range.
2) Read the TIP mode SW data of body inte-
grated module using Subaru Select Monitor. 
<Ref. to LAN(diag)-14, OPERATION, Subaru 
Select Monitor.>

Is OFF displayed?

Go to step 3.

Go to step 7.

3

CHECK BODY INTEGRATED MODULE IN-
PUT SIGNAL.
1) Shift the select lever from “P” to “D” range.
2) Read the TIP mode SW data of body inte-
grated module using Subaru Select Monitor. 
<Ref. to LAN(diag)-14, OPERATION, Subaru 
Select Monitor.>

Is the indication on each range 
OFF?

Go to step 4.

Replace the select 
lever assembly. 
<Ref. to CS-22, 
Select Lever.>

4

CHECK BODY INTEGRATED MODULE IN-
PUT SIGNAL.
1) Shift the select lever to manual mode.
2) Shift the select lever to other than “D” 
range.
3) Read the TIP mode SW data of body inte-
grated module using Subaru Select Monitor. 
<Ref. to LAN(diag)-14, OPERATION, Subaru 
Select Monitor.>

Is OFF displayed?

Go to step 5.

Replace the select 
lever assembly. 
<Ref. to CS-22, 
Select Lever.>

5

CHECK DTC OF TCM.

Is DTC of Transmission Range 
Sensor Circuit (PRNDL Input) 
and AT CAN communication 
circuit displayed?

Perform the diag-
nosis according to 
each DTC.

Go to step 6.

6

CHECK TCM INPUT SIGNAL.
1) Shift the select lever from “P” to “D” range.
2) Read the TIP mode SW data of TCM using 
Subaru Select Monitor. <Ref. to 5AT(diag)-17, 
OPERATION, Subaru Select Monitor.>

Is the indication on each range 
OFF?

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.

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

7

CHECK HARNESS BETWEEN BODY INTE-
GRATED MODULE AND SWITCH FOR 
SPORT MODE AND MANUAL MODE.
1) Turn the ignition switch to OFF.
2) Disconnect harness connector from body 
integrated module and select lever.
3) Measure the harness resistance between 
body integrated module and chassis ground.

Connector & terminal

(B281) No. 26 — Chassis ground:

Is the resistance more than 1 
M

Ω? 

Go to step 8.

Repair the short 
circuit of harness 
between body inte-
grated module and 
switch for SPORT 
mode and manual 
mode.