Subaru Legacy (2005 year). Service manual — part 812

VDC(diag)-113

VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

Step

Check

Yes

No

1

CHECK POWER SUPPLY FOR YAW RATE &
LATERAL G SENSOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from yaw rate &
lateral G sensor.
3) Turn the ignition switch to ON.
4) Measure the voltage between yaw rate &
lateral G sensor and chassis ground.

Connector & terminal

(B230) No. 3 (+) — Chassis ground (

−

):

Is the voltage 10 — 15 V?

Go to step 3.

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 yaw
rate & lateral G
sensor and
VDCCM&H/U.

Go to step 5.

3

CHECK GROUND CIRCUIT OF YAW RATE &
LATERAL G SENSOR.
Measure the resistance between yaw rate &
lateral G sensor and chassis ground.

Connector & terminal

(B230) No. 6 — Chassis ground:

Is the resistance less than 0.5
Ω?

Go to step 6.

Go to step 4.

4

CHECK GROUND CIRCUIT OF VDCCM&H/U.
Measure the resistance between VDCCM&H/U
and chassis ground.

Connector & terminal

(B310) No. 16 — Chassis ground:

Is the resistance less than 0.5
Ω?

Repair the har-
ness between yaw
rate & lateral G
sensor and
VDCCM&H/U.

Go to step 5.

5

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

nector?

Correct or replace
the connector.

Go to step 9.

6

CHECK HARNESS OF YAW RATE & LATER-
AL G SENSOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from VDCCM&H/
U.
3) Measure the resistance between
VDCCM&H/U and yaw rate & lateral G sensor.

Connector & terminal

(B310) No. 1 — (B230) No. 1:

Is the resistance less than 0.5
Ω?

Go to step 7.

Repair the har-
ness between yaw
rate & lateral G
sensor and
VDCCM&H/U.

7

CHECK GROUND SHORT CIRCUIT OF HAR-
NESS.
Measure the resistance between VDCCM&H/U
and chassis ground.

Connector & terminal

(B310) No. 1 — Chassis ground:

Is the resistance more than 1
M

Ω?

Go to step 8.

Repair the har-
ness between yaw
rate & lateral G
sensor and
VDCCM&H/U.

8

CHECK YAW RATE & LATERAL G SENSOR.
1) Turn the ignition switch to OFF.
2) Install the yaw rate & lateral G sensor to
body.
3) Connect all the connectors.
4) Turn the ignition switch to ON.
5) Measure the voltage between VDCCM&H/
U connector terminals.

Connector & terminal

(B310) No. 1 (+) — No. 16 (

−

):

Is the voltage 2.1 — 2.9 V?

Go to step 9.

Replace the yaw
rate & lateral G
sensor. <Ref. to
VDC-15, Yaw Rate
and Lateral G Sen-
sor.>

VDC(diag)-114

VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

9

CHECK VDCCM&H/U.
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.

Step

Check

Yes

No

VDC(diag)-115

VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

BA:DTC C0072 EXCESSIVE VARIATION AMOUNT OF YAW RATE SENSOR

OUTPUT

DTC DETECTING CONDITION:
Defective yaw rate sensor
TROUBLE SYMPTOM:
VDC does not operate.
WIRING DIAGRAM:

VDC00222

28

2

1

30

3

16

6

B312

B347

4

2

1

3

5

6

B230

1

B230

B310

VDCCM & H/U

1

3

4 5 6

2

B312

1 2

B310

E

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

YAW RATE &

LATERAL G SENSOR

VDC(diag)-116

VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

Step

Check

Yes

No

1

CHECK DRIVING PLACE.
Check if the vehicle ran the road with banks or
sandy surface (which does not mean a dirt
road).

Did the vehicle run the road
with banks or sandy surface
(which does not mean a dirt
road)?

VDCCM&H/U may
record DTC when
the vehicle ran the
road with banks or
sandy surface
(which does not
mean a dirt road).

Go to step 2.

2

CHECK YAW RATE & LATERAL G SENSOR
INSTALLATION.

Is the yaw rate & lateral G sen-
sor installation bolt tightened to
7.5 N

⋅m (0.76 kgf-m, 5.5 ft-lb)?

Go to step 3.

Tighten the yaw
rate & lateral G
sensor installation
bolt.

3

CHECK YAW RATE & LATERAL G SENSOR
POWER SUPPLY.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from yaw rate &
lateral G sensor.
3) Turn the ignition switch to ON.
4) Measure the voltage between yaw rate &
lateral G sensor and chassis ground.

Connector & terminal

(B230) No. 3 (+) — Chassis ground (

−

):

Is the voltage 10 — 15 V?

Go to step 5.

Go to step 4.

4

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 yaw
rate & lateral G
sensor and
VDCCM&H/U.

Go to step 7.

5

CHECK GROUND CIRCUIT OF YAW RATE &
LATERAL G SENSOR.
Measure the resistance between yaw rate &
lateral G sensor and chassis ground.

Connector & terminal

(B230) No. 6 — Chassis ground:

Is the resistance less than 0.5
Ω?

Go to step 8.

Go to step 6.

6

CHECK GROUND CIRCUIT OF VDCCM&H/U.
Measure the resistance between VDCCM&H/U
and chassis ground.

Connector & terminal

(B310) No. 16 — Chassis ground:

Is the resistance less than 0.5
Ω?

Repair the har-
ness between yaw
rate & lateral G
sensor and
VDCCM&H/U.

Go to step 7.

7

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

nector?

Correct or replace
the connector.

Go to step 14.

8

CHECK HARNESS OF YAW RATE & LATER-
AL G SENSOR.
1) Disconnect the connector from VDCCM&H/
U.
2) Measure the resistance between
VDCCM&H/U and yaw rate & lateral G sensor.

Connector & terminal

(B310) No. 1 — (B230) No. 1:
(B310) No. 2 — (B230) No. 2:
(B310) No. 28 — (B230) No. 4:

Is the resistance less than 0.5
Ω?

Go to step 9.

Repair the har-
ness between yaw
rate & lateral G
sensor and
VDCCM&H/U.

9

CHECK GROUND SHORT CIRCUIT OF HAR-
NESS.
Measure the resistance between VDCCM&H/U
connector and chassis ground.

Connector & terminal

(B310) No. 1 — Chassis ground:
(B310) No. 2 — Chassis ground:
(B310) No. 28 — Chassis ground:

Is the resistance more than 1
M

Ω?

Go to step 10.

Repair the har-
ness between yaw
rate & lateral G
sensor and
VDCCM&H/U.