Subaru Legacy III (2000-2003 year). Manual - part 594

AT-110

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

15

CHECK HARNESS CONNECTOR BETWEEN 
TRANSFER DUTY SOLENOID AND TRANS-
MISSION.
Measure resistance of harness between trans-
mission connector and transmission ground.

Connector & terminal

(T4) No. 6 — Transmission ground:

Does the measured value exceed the specified 
value?

1 M

Ω

Even if “POWER” 
indicator lights up, 
the circuit has 
returned to a nor-
mal condition at 
this time. A tempo-
rary poor contact 
of the connector or 
harness may be 
the cause. Repair 
harness or con-
tact in the transfer 
duty solenoid and 
transmission con-
nector.

Repair short circuit 
in harness 
between transfer 
duty solenoid and 
transmission con-
nector.

Step

Value

Yes

No

AT-111

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

MEMO:

AT-112

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

R: DTC 86 VDC COMMUNICATION SIGNAL

DIAGNOSIS:
Input signal circuit of TCM is open or shorted.
WIRING DIAGRAM:

AT-00784

TWISTED WIRE

TWISTED WIRE

B62

F45

B234

1 2 3 4 5 6

B56

1 2

7

8

9

5 6

3 4

10 11 12
19 20 21

13

14 15

16

17

18

22

23

24

9

18

1
4
6
3

B234

TCM

B56

83

81

VDC CM

F87

F87

56 57

59 60

62 63

65

82 83

80

27

28

25

26

23

24

21

22

19

20

17

18

15

16

13

14

11

12

9

10

7

8

5

6

3

4

1

2

54

55

52

53

50

51

81

48

49

46

47

44

45

78

79

76

77

75

42

43

40

41

74

72

73

70

71

39

37

38

35

36

69

67

68

66

33

34

61

64

31

32

29

30

58

51

LH

6

RH

2

JOINT 
CONNECTOR

F96

LH

RH

: LHD MODEL

: RHD MODEL

1 2 3

4 5 6

7 8 9 10 11 12 13 14

AT-113

AUTOMATIC TRANSMISSION (DIAGNOSTICS)

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

Step

Value

Yes

No

1

CHECK TROUBLE CODE.
Do multiple trouble codes appear in the on-
board diagnostics test mode?

DTC is displayed.

Go to another trou-
ble code.

Go to step 2.

2

CHECK HARNESS CONNECTOR BETWEEN 
TCM AND VDCCM.
1) Turn ignition switch to OFF.
2) Disconnect connector from TCM and 

VDCCM.

3) Measure resistance of harness between 

TCM and VDCCM connector.

Connector & terminal

(B56) No. 18 — (F87) No. 81:

Is the measured value less than the speci-
fied value?

1 

Ω

Go to step 3.

Repair open circuit 
in harness 
between TCM and 
VDCCM, and poor 
contact in cou-
pling connector.

3

CHECK HARNESS CONNECTOR BETWEEN 
TCM AND VDCCM.
Measure resistance of harness between TCM 
and VDCCM connector.

Connector & terminal

(B56) No. 9 — (F87) No. 83:

Is the measured value less than the specified 
value?

1 

Ω

Go to step 4.

Repair open circuit 
in harness 
between TCM and 
VDCCM, and poor 
contact in cou-
pling connector.

4

CHECK HARNESS CONNECTOR BETWEEN 
TCM AND VDCCM.
Measure resistance of harness between TCM 
and VDCCM connector.

Connector & terminal

(B56) No. 18 — Chassis ground:

Is the measured value less than the specified 
value?

1 M

Ω

Go to step 5.

Repair short circuit 
in harness 
between TCM and 
VDCCM connec-
tor.

5

CHECK HARNESS CONNECTOR BETWEEN 
TCM AND VDCCM.
Measure resistance of harness between TCM 
and VDCCM connector.

Connector & terminal

(B56) No. 9 — Chassis ground:

Is the measured value less than the specified 
value?

1 M

Ω

Go to step 6.

Repair short circuit 
in harness 
between TCM and 
VDCCM connec-
tor.

6

PREPARE OSCILLOSCOPE.
Do you have oscilloscope?

Oscilloscope is available.

Go to step 8.

Go to step 7.

7

CHECK INPUT SIGNAL FOR TCM.
1) Connect connectors to TCM and VDCCM.
2) Turn ignition switch to ON (engine OFF).
3) Measure voltage between TCM connector 

and chassis ground.

Connector & terminal

(B56) No. 9 (+) — Chassis ground (

−−−−

):

(B56) No. 18 (+) — Chassis ground (

−−−−

):

Does input voltage value change?

Input voltage varies.

Go to step 10.

Repair poor con-
tact in VDCCM.