Subaru Legacy III (2000-2003 year). Manual - part 785

VDC-176

VDC (DIAGNOSTICS)

DIAGNOSTICS CHART WITH SELECT MONITOR

AB:DTC 44 TCM COMMUNICATION CIRCUIT

DIAGNOSIS:
• Communication with AT control faults
TROUBLE SYMPTOM:
• VDC does not operate.
WIRING DIAGRAM:

VDC00178

B234

STEERING ANGLE SENSOR

9

18

4

2

1

3

2
3
1
5
6
4

81

27

83

1

15

R

2

5

9

L

6

B231

VDC

CONTROL

MODULE

F96

B225

F87

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

B231

1 2 3 4

B234

1 2 3 4 5 6

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

B56

TCM

1 2 3

4 5 6

7 8 9 10 11 12 13 14

F96

L

:

F96

R

:

R

L

1 2 3 4

5 6 7 8 9

10 11 12 13 14 15 16 17 18 19 20

: RHD MODEL

: LHD MODEL

VDC-177

VDC (DIAGNOSTICS)

DIAGNOSTICS CHART WITH SELECT MONITOR

Step

Value

Yes

No

1

CHECK RESISTANCE OF HARNESS.
1) Turn ignition switch to OFF.
2) Disconnect two connectors from TCM.
3) Measure resistance between TCM connec-

tor terminals.

Connector & terminal

(B56) No. 9 — No. 18:

Is the measured value within the specified 
range?

57 — 63 

Ω

Go to step 2.

Repair harness 
between TCM and 
VDCCM.

2

CHECK POOR CONTACT IN CONNECTORS.
Is there poor contact in TCM connectors?

There is poor contact.

Repair connector.

Go to step 3.

3

CHECK TCM.
1) Turn ignition switch to OFF.
2) Connect all connectors.
3) Erase the memory.
4) Perform inspection mode.
5) Read out the diagnostic trouble code.

Is the same diagnostic trouble code as in 
the current diagnosis still being output?

Same DTC indicated.

Replace TCM.  
<Ref. to AT-76, 
Transmission Con-
trol Module 
(TCM).>

Go to step 4.

4

CHECK ANY OTHER DIAGNOSTIC TROU-
BLE CODES APPEARANCE.
Are other diagnostic trouble codes being out-
put?

Other DTC indicated.

Proceed with the 
diagnosis corre-
sponding to the 
diagnostic trouble 
code.

A temporary poor 
contact.

VDC-178

VDC (DIAGNOSTICS)

DIAGNOSTICS CHART WITH SELECT MONITOR

AC:DTC 45 INCORRECT VDC CONTROL MODULE

DIAGNOSIS:
• Control module out of specification
TROUBLE SYMPTOM:
• ABS does not operate.
• VDC does not operate.

Step

Value

Yes

No

1

CHECK VDCCM SPECIFICATIONS.
Check the VDCCM identification mark.

VDCCM identification mark

H4 engine model

K

OUTBACK H4 enigne model

M

OUTBACK H6 enigne model

N

 H4 enigne model for Australia

J

 H6 enigne model for Australia OUT-
BACK

Y

Does the VDCCM identification mark agree 
with the vehicle specifications?

Agree.

Go to step 2.

Replace VDCCM.  
<Ref. to VDC-8, 
VDC Control Mod-
ule (VDCCM).>

2

CHECK TCM SPECIFICATIONS.
Check the TCM identification mark.

TCM identification mark

LHD H4 engine model

YZ

RHD H4 engine model

ZG

LHD OUTBACK H4 enigne model

ZB

RHD OUTBACK H4 enigne model

ZJ

LHD OUTBACK H6 enigne model

ZD

RHD OUTBACK H6 enigne model

ZL

Does the TCM identification mark agree with 
the vehicle specifications?

Agree.

Go to step 3.

Replace TCM.  
<Ref. to AT-76, 
Transmission Con-
trol Module 
(TCM).>

3

CHECK TCM.
1) Replace TCM.  <Ref. to AT-76, Transmis-

sion Control Module (TCM).>

2) Erase the memory.
3) Perform inspection mode.
4) Read out the diagnostic trouble code.

Is the same diagnostic trouble code as in 
the current diagnosis still being output?

Same DTC indicated.

Go to step 4.

The original TCM 
has been faulty.

4

CHECK TCM.

Is the same diagnostic trouble 
code as in the current diagno-
sis still being output?

Go to step 5.

Proceed with the 
diagnosis corre-
sponding to the 
diagnostic trouble 
code.

VDC-179

VDC (DIAGNOSTICS)

DIAGNOSTICS CHART WITH SELECT MONITOR

5

CHECK VDCCM.
1) Install original TCM.
2) Replace VDCCM.  <Ref. to VDC-8, VDC 

Control Module (VDCCM).>

3) Erase the memory.
4) Perform inspection mode.
5) Read out the diagnostic trouble code.

Is the same diagnostic trouble code as in 
the current diagnosis still being output?

Same DTC indicated.

Go to step 6.

The original 
VDCCM has been 
faulty.

6

CHECK VDCCM.
Is the same diagnostic trouble code as in the 
current diagnosis still being output?

Same DTC indicated.

Replace TCM.  
<Ref. to AT-76, 
Transmission Con-
trol Module 
(TCM).>

Proceed with the 
diagnosis corre-
sponding to the 
diagnostic trouble 
code.

Step

Value

Yes

No