Subaru Impreza 3 / Impreza WRX / Impreza WRX STI. Manual — part 548

VDC(diag)-91

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)

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

2.

Repair the steering
angle sensor
power supply cir-
cuit.

2

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 10

Ω?

Go to step

3.

Repair ground cir-
cuit in the steering
angle sensor.

3

CHECK STEERING ANGLE SENSOR.
1) Turn the ignition switch to OFF.
2) Connect all connectors.
3) Clear the memory. <Ref. to VDC(diag)-27,
Clear Memory Mode.>
4) Perform the Inspection Mode. <Ref. to
VDC(diag)-26, Inspection Mode.>
5) Read the DTC.

Is the same DTC displayed?

Go to step

4.

Go to step

5.

4

CHECK VDCCM&H/U.
1) Turn the ignition switch to OFF.
2) Replace the steering angle sensor. <Ref. to
VDC-22, Steering Angle Sensor.>
3) Clear the memory. <Ref. to VDC(diag)-27,
Clear Memory Mode.>
4) Perform the Inspection Mode. <Ref. to
VDC(diag)-26, Inspection Mode.>
5) Read the DTC.

Is the same DTC displayed?

Replace the
VDCCM only.
<Ref. to VDC-12,
REPLACEMENT,
VDC Control Mod-
ule and Hydraulic
Control Unit
(VDCCM&H/U).>

Go to step

6.

5

CHECK OTHER DTC DETECTION.

Is any other DTC displayed?

Perform the diag-
nosis according to
DTC. <Ref. to
VDC(diag)-48, List
of Diagnostic Trou-
ble Code (DTC).>

Temporary poor
contact occurs.

6

CHECK OTHER DTC DETECTION.

Is any other DTC displayed?

Perform the diag-
nosis according to
DTC. <Ref. to
VDC(diag)-48, List
of Diagnostic Trou-
ble Code (DTC).>

Original steering
angle sensor mal-
function

VDC(diag)-92

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)

AP:DTC C0072 ABNORMAL YAW RATE SENSOR OUTPUT

DTC DETECTING CONDITION:

Defective yaw rate sensor

TROUBLE SYMPTOM:

VDC does not operate.

Step

Check

Yes

No

1

INTERVIEW CUSTOMERS.
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 & G SENSOR INSTAL-
LATION.

Is the yaw rate & G sensor
installation bolt tightened to 7.5
N·m (0.76 kgf-m, 5.5 ft-lb)?

Go to step

3.

Tighten the yaw
rate & G sensor
installation bolt.

3

CHECK OUTPUT OF YAW RATE & G SEN-
SOR WITH SUBARU SELECT MONITOR.
1) Drive the vehicle on a flat road.
2) Park the vehicle straight.
3) Select “Current Data Display & Save” on the
Subaru Select Monitor. <Ref. to VDC(diag)-19,
READ CURRENT DATA, OPERATION, Subaru
Select Monitor.>
4) Read the «Yaw Rate Sensor Output» dis-
played on display.

Is the reading indicated on
monitor display –4 — 4 deg/s?

Go to step

4.

Replace the yaw
rate & G sensor.
<Ref. to VDC-20,
Yaw Rate and G
Sensor.>

4

CHECK OUTPUT OF STEERING ANGLE
SENSOR WITH SUBARU SELECT MONI-
TOR.
1) Drive the vehicle on a flat road.
2) Park the vehicle straight.
3) Select “Current Data Display & Save” on the
Subaru Select Monitor. <Ref. to VDC(diag)-19,
READ CURRENT DATA, OPERATION, Subaru
Select Monitor.>
4) Read the «Steer Angle Sensor Op» dis-
played on display.

Is the reading indicated on
monitor display –5 — 5°?

Go to step

5.

Perform the cen-
tering adjustment
of steering wheel.

5

CHECK YAW RATE & G SENSOR.
1) Turn the ignition switch to OFF.
2) Connect all connectors.
3) Clear the memory. <Ref. to VDC(diag)-27,
Clear Memory Mode.>
4) Perform the Inspection Mode. <Ref. to
VDC(diag)-26, Inspection Mode.>
5) Read the DTC.

Is the same DTC displayed?

Go to step

6.

Go to step

7.

6

CHECK VDCCM&H/U.
1) Turn the ignition switch to OFF.
2) Replace the yaw rate & G sensor. <Ref. to
VDC-20, Yaw Rate and G Sensor.>
3) Clear the memory. <Ref. to VDC(diag)-27,
Clear Memory Mode.>
4) Perform the Inspection Mode. <Ref. to
VDC(diag)-26, Inspection Mode.>
5) Read the DTC.

Is the same DTC displayed?

Replace the
VDCCM only.
<Ref. to VDC-12,
REPLACEMENT,
VDC Control Mod-
ule and Hydraulic
Control Unit
(VDCCM&H/U).>

Go to step

8.

VDC(diag)-93

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)

7

CHECK OTHER DTC DETECTION.

Is any other DTC displayed?

Perform the diag-
nosis according to
DTC. <Ref. to
VDC(diag)-48, List
of Diagnostic Trou-
ble Code (DTC).>

Temporary poor
contact occurs.

8

CHECK OTHER DTC DETECTION.

Is any other DTC displayed?

Perform the diag-
nosis according to
DTC. <Ref. to
VDC(diag)-48, List
of Diagnostic Trou-
ble Code (DTC).>

Malfunction is
found in original
yaw rate & G sen-
sor.

Step

Check

Yes

No

VDC(diag)-94

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)

AQ:DTC C0072 VOLTAGE INPUTTED TO YAW RATE SENSOR EXCEEDS SPEC-

IFICATION

DTC DETECTING CONDITION:

Defective yaw rate sensor

TROUBLE SYMPTOM:

VDC does not operate.

WIRING DIAGRAM:

Vehicle Dynamics Control System <Ref. to WI-67, Vehicle Dynamics Control System.>

VDC00702

1 2 3 4

B310 VDCCM & H/U

25

10

35

B231

B230

2

4

1

3

1

4

2

3

STEERING

ANGLE

SENSOR

YAW RATE &

G SENSOR

E

B231

SBF-6

MAIN SBF

No.33

E

IGNITION SWITCH

BATTERY

E

B310

4 5 6 7 8 9

26 27 28 29 30

2 3

1

31 32 33 34 35 36

10 11

14 15 16 17 18 19

37 38 39 40

12 13

41 42 43 44 45 46

20 21

23 24

22

25

B230

1

2

3

4

TWISTED P

AIR LINE

TWISTED P

AIR LINE

TWISTED PAIR LINE