Subaru Legacy III (2000-2003 year). Manual - part 794

VDC-212

VDC (DIAGNOSTICS)

DIAGNOSTICS CHART WITH SELECT MONITOR

16

CHECK POOR CONTACT IN CONNECTORS.
Turn ignition switch to OFF.
Is there poor contact in connector between 
VDCCM and VDCH/U?

There is poor contact.

Repair connector.

Go to step 17.

17

CHECK VDCCM.
1) Connect all connectors.
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.

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

Go to step 18.

18

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.

Step

Value

Yes

No

VDC-213

VDC (DIAGNOSTICS)

DIAGNOSTICS CHART WITH SELECT MONITOR

MEMO:

VDC-214

VDC (DIAGNOSTICS)

DIAGNOSTICS CHART WITH SELECT MONITOR

AM:DTC 52 MOTOR AND MOTOR RELAY OFF FAILURE

DIAGNOSIS:
• Faulty motor relay
• Faulty harness connector
TROUBLE SYMPTOM:
• ABS does not operate.
• VDC does not operate.
WIRING DIAGRAM:

VDC00155

VDC HYDRAULIC UNIT

87

87a

VDC2

VDC1

4

6

86

1

85

30

30

86

85

87

5

VDC4

F90

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

SBF HOLDER 50A

VDC7

VDC6

MOTOR RELAY

VALVE RELAY

VDC CONTROL MODULE

22

10

27

47

F87

1

VDC3

F89

2

SBF-1 100A

RELAY BOX

F89

VDC1

1 2

F90

VDC6

1

3

4 5 6

2

85

86

87

30

85 87a 86

87

30

VDC7

BATTERY

VDC-215

VDC (DIAGNOSTICS)

DIAGNOSTICS CHART WITH SELECT MONITOR

Step

Value

Yes

No

1

CHECK CONTACT POINT OF MOTOR RE-
LAY.
1) Turn ignition switch to OFF.
2) Remove motor relay from relay box.
3) Measure resistance between motor relay 

terminals.

Terminals

No. 30 — No. 87:

Does the measured value exceed the spec-
ified value?

1 M

Ω

Go to step 2.

Replace motor 
relay.

2

CHECK SHORT OF MOTOR RELAY.
Measure resistance between motor relay ter-
minals.

Terminals

No. 85 — No. 30:
No. 85 — No. 87:

Does the measured value exceed the specified 
value?

1 M

Ω

Go to step 3.

Replace motor 
relay.

3

CHECK GROUND SHORT IN CIRCUIT OF 
RELAY BOX.
1) Disconnect connector (F90) from relay box.
2) Measure resistance between relay box con-

nector unit and chassis ground.

Connector & terminal

(VDC4) No. 4 — Chassis ground:

Does the measured value exceed the spec-
ified value?

1 M

Ω

Go to step 4.

Replace relay box.

4

CHECK BATTERY SHORT IN CIRCUIT OF 
RELAY BOX.
Measure voltage between relay box connector 
and chassis ground.

Connector & terminal

(VDC4) No. 6 (+) — Chassis ground (

−−−−

):

Is the measured value less than the specified 
value?

1 V

Go to step 5.

Replace relay box.

5

CHECK BATTERY SHORT IN CIRCUIT OF 
RELAY BOX.
1) Turn ignition switch to ON.
2) Measure voltage between relay box con-

nector and chassis ground.

Connector & terminal

(VDC4) No. 6 (+) — Chassis ground (

−−−−

):

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

1 V

Go to step 6.

Replace relay box.

6

CHECK GROUND SHORT IN HARNESS BE-
TWEEN RELAY BOX AND VDCCM.
1) Turn ignition switch to OFF.
2) Disconnect connector from VDCCM.
3) Measure resistance between VDCCM con-

nector and chassis ground.

Connector & terminal

(F87) No. 22 — Chassis ground:

Does the measured value exceed the spec-
ified value?

1 M

Ω

Go to step 7.

Repair harness 
between VDCCM 
and relay box. 
Check fuse SBF 
holder.