Subaru Legacy (2005 year). Manual - part 795

VDC(diag)-45

VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

D: DTC C0027 REAR ABS WHEEL SPEED SENSOR LH POWER SUPPLY MAL-

FUNCTION

DTC DETECTING CONDITION:
Defective ABS wheel speed sensor
TROUBLE SYMPTOM:
• ABS does not operate.
• VDC does not operate.
WIRING DIAGRAM:

VDC00309

MAIN SBF

SBF-6

No.33

B310

B310

E

E

6

14

VDCCM & H/U

1 2 3 4

11 12 13 14
27 28 29 30

15 16 17 18
31 32 33 34

19 20 21 22
35 36 37 38

23 24 25 26
39 40 41 42

5

6

7

8

9

10

BATTERY

GENERATOR

IGNITION
SWITCH

VDC(diag)-46

VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

E: DTC C0021 OPEN/HIGH INPUT OF FRONT ABS WHEEL SPEED SENSOR RH

NOTE:
For the diagnostic procedure, refer to DTC C0027 “OPEN/HIGH INPUT OF REAR ABS WHEEL SPEED
SENSOR LH”. <Ref. to VDC(diag)-47, DTC C0027 OPEN/HIGH INPUT OF REAR ABS WHEEL SPEED
SENSOR LH, Diagnostic Procedure with Diagnostic Trouble Code (DTC).>

F: DTC C0023 OPEN/HIGH INPUT OF FRONT ABS WHEEL SPEED SENSOR LH

NOTE:
For the diagnostic procedure, refer to DTC C0027 “OPEN/HIGH INPUT OF REAR ABS WHEEL SPEED
SENSOR LH”. <Ref. to VDC(diag)-47, DTC C0027 OPEN/HIGH INPUT OF REAR ABS WHEEL SPEED
SENSOR LH, Diagnostic Procedure with Diagnostic Trouble Code (DTC).>

G: DTC C0025 OPEN/HIGH INPUT OF REAR ABS WHEEL SPEED SENSOR RH

NOTE:
For the diagnostic procedure, refer to DTC C0027 “OPEN/HIGH INPUT OF REAR ABS WHEEL SPEED
SENSOR LH”. <Ref. to VDC(diag)-47, DTC C0027 OPEN/HIGH INPUT OF REAR ABS WHEEL SPEED
SENSOR LH, Diagnostic Procedure with Diagnostic Trouble Code (DTC).>

Step

Check

Yes

No

1

CHECK POOR CONTACT IN CONNECTOR.
Check if there is poor contact in VDCCM&H/U 
power supply circuit.

Is there poor contact?

Repair the con-
nector.

Go to step 2.

2

CHECK VDCCM&H/U POWER SUPPLY CIR-
CUIT.
1) Turn the ignition switch to OFF.
2) Disconnect the VDCCM&H/U connector.
3) Turn the ignition switch to ON.
4) Measure the voltage between VDCCM&H/
U connector terminals.

Terminals

(B310) No. 14 (+) — (B310) No. 6 (

−

):

Is the voltage 10 — 15 V?

Go to step 3.

Check the genera-
tor, battery and 
VDCCM&H/U 
power supply cir-
cuit.

3

CHECK VDCCM&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 
VDCCM&H/U.

Go to step 4.

4

CHECK OTHER DTC DETECTION.

Is any other DTC displayed?

Perform the diag-
nosis according to 
DTC.

It results from a 
temporary noise 
interference.

VDC(diag)-47

VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

H: DTC C0027 OPEN/HIGH INPUT OF REAR ABS WHEEL SPEED SENSOR LH

DTC DETECTING CONDITION:
• Defective ABS wheel speed sensor (broken wire, input voltage too high)
• Defective harness connector
TROUBLE SYMPTOM:
• ABS does not operate.
• VDC does not operate.
WIRING DIAGRAM:
• LHD model

B15

B6

R73

R72

B310

B98

1 2 3 4

11 12 13 14
27 28 29 30

15 16 17 18
31 32 33 34

19 20 21 22
35 36 37 38

23 24 25 26
39 40 41 42

5

6

7

8

9

10

VDC00299

38

23

25

41

40

24

6

B98

R72

R2

E

1

2

15

14

6

5

R73

1

2

1

2

1

2

B6

B15

21

22

B310

VDCCM & H/U

TWISTED WIRE

FRONT ABS

WHEEL SPEED

SENSOR LH

TWISTED WIRE

TWISTED WIRE

TWISTED WIRE

FRONT ABS

WHEEL SPEED

SENSOR RH

REAR ABS

WHEEL SPEED

SENSOR LH

REAR ABS

WHEEL SPEED

SENSOR RH

1 2

1 2 3

4 5 6 7

8 9 10 11 12 13 14 15 16

VDC(diag)-48

VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

• RHD model

VDC00326

38

23

25

41

40

24

6

B97

R72

R1

E

1

2

19

18

8

7

R73

1

2

1

2

1

2

B6

B15

B15

B6

R73

R72

B310

21

22

B310

B97

VDCCM & H/U

TWISTED WIRE

FRONT ABS

WHEEL SPEED

SENSOR LH

1 2 3 4

11 12 13 14
27 28 29 30

15 16 17 18
31 32 33 34

19 20 21 22
35 36 37 38

23 24 25 26
39 40 41 42

5

6

7

8

9

10

1 2 3 4

5 6 7 8 9

10 11 12 13 14 15 16 17 18 19 20

TWISTED WIRE

TWISTED WIRE

TWISTED WIRE

FRONT ABS

WHEEL SPEED

SENSOR RH

REAR ABS

WHEEL SPEED

SENSOR LH

REAR ABS

WHEEL SPEED

SENSOR RH

1 2