Subaru Legacy (2005 year). Manual - part 809

VDC(diag)-101

VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

• RHD model

VDC00247

30

29

13

B231

E

2

4

1

3

B310

B310

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

1 2 3 4

B231

TWISTED WIRE

STEERING
ANGLE SENSOR

VDC(diag)-102

VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

Step

Check

Yes

No

1

CHECK POWER SUPPLY FOR STEERING 
ANGLE SENSOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from steering 
angle sensor.
3) Turn the ignition switch to ON.
4) Measure the voltage between steering 
angle sensor and chassis ground.

Connector & terminal

(B231) No. 4 (+) — Chassis ground (

−

):

Is the voltage 10 — 15 V?

Go to step 4.

Go to step 2.

2

CHECK OUTPUT VOLTAGE OF VDCCM&H/
U.
Measure the voltage between VDCCM&H/U 
and chassis ground.

Connector & terminal

(B310) No. 30 (+) — Chassis ground (

−

):

Is the voltage 10 — 15 V?

Repair the har-
ness between 
steering angle 
sensor and 
VDCCM&H/U.

Go to step 3.

3

CHECK POOR CONTACT IN CONNECTORS. Is there poor contact in con-

nector?

Correct or replace 
the connector.

Go to step 9.

4

CHECK GROUND CIRCUIT OF STEERING 
ANGLE SENSOR.
Measure the resistance between steering 
angle sensor and chassis ground.

Connector & terminal

(B231) No. 3 — Chassis ground:

Is the resistance less than 0.5 
Ω?

Go to step 5.

Repair ground cir-
cuit in the steering 
angle sensor.

5

CHECK STEERING ANGLE SENSOR HAR-
NESS.
1) Disconnect the connector from VDCCM&H/
U.
2) Measure the resistance between 
VDCCM&H/U and steering angle sensor.

Connector & terminal

(B231) No. 1 — (B310) No. 29:
(B231) No. 2 — (B310) No. 13:

Is the resistance less than 0.5 
Ω?

Go to step 6.

Repair the har-
ness between 
steering angle 
sensor and 
VDCCM&H/U.

6

CHECK GROUND SHORT CIRCUIT OF 
STEERING ANGLE SENSOR HARNESS.
Measure the resistance between steering 
angle sensor and chassis ground.

Connector & terminal

(B231) No. 1 — Chassis ground:
(B231) No. 2 — Chassis ground:

Is the resistance more than 1 
M

Ω?

Go to step 7.

Repair the har-
ness between 
steering angle 
sensor and 
VDCCM&H/U.

7

CHECK STEERING ANGLE SENSOR.
1) Turn the ignition switch to OFF.
2) Connect all the connectors.
3) Perform the clear memory mode.
4) Perform the inspection mode.
5) Read the DTC.

Is the same DTC displayed?

Go to step 8.

Go to step 10.

8

CHECK VDCCM&H/U.
1) Turn the ignition switch to OFF.
2) Replace the steering angle sensor.
3) Perform the clear memory mode.
4) Perform the inspection mode.
5) Read the DTC.

Is the same DTC displayed?

Replace the 
VDCCM&H/U. 
<Ref. to VDC-7, 
VDC Control Mod-
ule and Hydraulic 
Control Unit 
(VDCCM&H/U).>

Go to step 11.

VDC(diag)-103

VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

AW:DTC C0071 STEERING ANGLE SENSOR POWER SUPPLY MALFUNCTION

DTC DETECTING CONDITION:
Defective steering angle sensor
TROUBLE SYMPTOM:
• ABS does not operate.
• VDC does not operate.

NOTE:
• Warning light does not illuminate though problem is detected.
• The ABS and VDC operate normally if voltage returns.

9

CHECK STEERING ANGLE SENSOR.
1) Turn the ignition switch to OFF.
2) Connect all the connectors.
3) Perform the clear memory mode.
4) Perform the inspection mode.
5) Read the DTC.

Is the same DTC displayed?

Replace the 
VDCCM&H/U. 
<Ref. to VDC-7, 
VDC Control Mod-
ule and Hydraulic 
Control Unit 
(VDCCM&H/U).>

Go to step 10.

10

CHECK OTHER DTC DETECTION.

Is any other DTC displayed?

Perform the diag-
nosis according to 
DTC.

Temporary poor 
contact occurs.

11

CHECK OTHER DTC DETECTION.

Is any other DTC displayed?

Perform the diag-
nosis according to 
DTC.

Original steering 
angle sensor mal-
function

Step

Check

Yes

No

VDC(diag)-104

VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

WIRING DIAGRAM:
• LHD model

VDC00327

30

29

13

B231

B234

E

2

4

1

3

3

1

4

2

B310

B310

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

1 2 3 4

B231

TWISTED WIRE

STEERING
ANGLE SENSOR

B234

3 4

5 6

1 2

7 8

B352

3

1

4

2

B352