Subaru Legacy (2005 year). Service manual — part 814

VDC(diag)-121

VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

BF:DTC C0073 LATERAL G SENSOR POWER/OUTPUT

DTC DETECTING CONDITION:
Defective lateral G sensor
DTC DETECTING CONDITION:
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)-122

VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

Step

Check

Yes

No

1

CHECK LATERAL G SENSOR OUTPUT.
1) Park the vehicle on a level surface.
2) Select {Current Data Display & Save} in
Subaru Select Monitor.
3) Read the lateral G sensor output displayed
on display.

Is the indicated reading on the
monitor display

−1.5 —1.5 m/

s

2

?

Go to step 2.

Go to step 3.

2

CHECK POOR CONTACT IN CONNECTORS.
Turn the ignition switch to OFF.

Is there poor contact in con-
nector between VDCCM&H/U
and yaw rate & lateral G sen-
sor?

Repair the con-
nector.

Go to step 10.

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 6.

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 5.

5

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

nector?

Correct or replace
the connector.

Go to step 10.

6

CHECK OPEN CIRCUIT IN LATERAL G SEN-
SOR OUTPUT HARNESS.
1) Disconnect the connector from yaw rate &
lateral G sensor.
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. 3 — (B230) No. 5:

Is the resistance less than 0.5
Ω?

Go to step 7.

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

7

CHECK GROUND SHORT CIRCUIT FOR
YAW RATE & LATERAL G SENSOR HAR-
NESS.
Measure the resistance between VDCCM&H/U
connector and chassis ground.

Connector & terminal

(B310) No. 3 — Chassis ground:

Is the resistance more than 1
M

Ω?

Go to step 8.

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

8

CHECK LATERAL G SENSOR.
1) Turn the ignition switch to OFF.
2) Remove the yaw rate & lateral G sensor
from vehicle.
3) Connect the connector to the yaw rate &
lateral G sensor.
4) Connect the connector to VDCCM&H/U.
5) Turn the ignition switch to ON.
6) Measure the voltage between yaw rate &
lateral G sensor connector terminals.

Connector & terminal

(B230) No. 5 (+) — No. 6 (

−

):

Is the voltage 2.35 — 2.65 V
when yaw rate & lateral G sen-
sor is on level?

Go to step 9.

Replace the yaw
rate & lateral G
sensor.

VDC(diag)-123

VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

9

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

nector between VDCCM&H/U
and yaw rate & lateral G sen-
sor?

Repair the con-
nector.

Go to step 10.

10

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

Go to step 11.

11

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)-124

VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

BG:DTC C0074 PRESSURE SENSOR TEST MALFUNCTION

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

VDC00223

27

11

12

B348

B348

1

2

3

B310

VDCCM & H/U

B310

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

PRESSURE SENSOR