Subaru Impreza 3 / Impreza WRX / Impreza WRX STI. Manual — part 523

VDC-21

Yaw Rate and G Sensor

VEHICLE DYNAMICS CONTROL (VDC)

C: INSPECTION

1. YAW RATE & G SENSOR SIGNAL

Step

Check

Yes

No

1

CHECK YAW RATE & G SENSOR.
1) Turn the ignition switch to OFF.
2) Connect the Subaru Select Monitor connec-
tor to the data link connector.
3) Turn the ignition switch to ON.
4) Set the Subaru Select Monitor connector to
the {Brake Control System} mode.
5) Select {Current Data Display & Save}.
6) Read the output of yaw rate & G sensor.

Are the indicated values when
the vehicle is placed horizon-
tally, Lateral G sensor: –1.5 —
1.5 m/s

2

, Yaw rate sensor: –4

— 4 deg/s?

Go to step

2.

Repair the harness
connector between
yaw rate & G sen-
sor and
VDCCM&H/U. Or
replace yaw rate &
G sensor.

2

CHECK G SENSOR.
1) Remove the console box.
2) Remove the yaw rate & G sensor from vehi-
cle without disconnecting the connector.
3) Read the display of Subaru Select Monitor.
NOTE:

When the yaw rate & G sensor is moved with its
power supply on, DTC of yaw rate & G sensor
may be recorded.

Is the value 6.8 — 12.8 m/s

2

when the yaw rate & G sensor
is inclined 90° to the forward?

Go to step

3.

Repair the harness
connector between
yaw rate & G sen-
sor and
VDCCM&H/U. Or
replace yaw rate &
G sensor.

3

CHECK G SENSOR.
Read the display of Subaru Select Monitor.
NOTE:

When the yaw rate & G sensor is moved with its
power supply on, DTC of yaw rate & G sensor
may be recorded.

Is the value –6.8 — –12.8 m/s

2

when the yaw rate & G sensor
is inclined 90° to the rearward?

Go to step

4.

Repair the harness
connector between
yaw rate & G sen-
sor and
VDCCM&H/U. Or
replace yaw rate &
G sensor.

4

CHECK G SENSOR.
Read the display of Subaru Select Monitor.
NOTE:

When the yaw rate & G sensor is moved with its
power supply on, DTC of yaw rate & G sensor
may be recorded.

Is the value 6.8 — 12.8 m/s

2

when the yaw rate & G sensor
is inclined 90° to the right?

Go to step

5.

Repair the harness
connector between
yaw rate & G sen-
sor and
VDCCM&H/U. Or
replace yaw rate &
G sensor.

5

CHECK G SENSOR.
Read the display of Subaru Select Monitor.
NOTE:

When the yaw rate & G sensor is moved with its
power supply on, DTC of yaw rate & G sensor
may be recorded.

Is the value –6.8 — –12.8 m/s

2

when the yaw rate & G sensor
is inclined 90° to the left?

Yaw rate & G sen-
sors are normal.

Repair the harness
connector between
yaw rate & G sen-
sor and
VDCCM&H/U. Or
replace yaw rate &
G sensor.

VDC-22

Steering Angle Sensor

VEHICLE DYNAMICS CONTROL (VDC)

7. Steering Angle Sensor

A: REPLACEMENT

CAUTION:

• Do not perform the removal except unless re-

placing.

• If the sensor needs replacement, replace

along with the combination switch assembly

once every three times for the protection of the

threaded portion.

1) Set the steering wheel in a straight-ahead posi-

tion.

2) Disconnect the ground cable from battery.

3) Remove the driver’s airbag module. <Ref. to AB-

15, REMOVAL, Driver’s Airbag Module.>
WARNING:

Always refer to “Airbag System” when perform-

ing the airbag module repair service. <Ref. to

AB-5, CAUTION, General Description.>

4) Remove the steering wheel. <Ref. to PS-13, RE-

MOVAL, Steering Wheel.>

5) Remove the screws and remove the steering

column cover lower.

6) Remove the harness cover lock.

7) Remove the screws and detach the knee protec-

tor.

8) Remove the screws and remove the steering

column cover upper.

9) Disconnect the connector of roll connector and

steering angle sensor.

10) Remove the screws which secure the roll con-

nector to steering column.

11) Remove the vinyl tape binding the harness,

and remove the steering angle sensor from roll

connector.

WW-00547

LI-01143

LI-01144

AB-02604

VDC00885

VDC-23

Steering Angle Sensor

VEHICLE DYNAMICS CONTROL (VDC)

12) Turn the protrusion portion of new steering an-

gle sensor to match the alignment mark of inspec-

tion hole.
CAUTION:

Be careful not to allow foreign matter to enter

into inspection hole.

13) Align the center of roll connector. <Ref. to AB-

26, INSTALLATION, Roll Connector.>

14) Apply the grease provided with the new part on

the 4 locations of the protrusion on the steering an-

gle sensor.

15) Align the position of the protrusion and install

roll connector to steering angle sensor.
Tightening torque:

0.5 N·m (0.05 kgf-m, 0.36 ft-lb)

16) Install the roll connector to combination switch

and bind the harness with vinyl tape as originally

bound.

17) Install the steering wheel. <Ref. to PS-13, IN-

STALLATION, Steering Wheel.>
Tightening torque:

39 N·m (3.98 kgf-m, 28.8 ft-lb)

18) Install the airbag module to the steering wheel.

<Ref. to AB-15, INSTALLATION, Driver’s Airbag

Module.>
WARNING:

Always refer to “Airbag System” before per-

forming the service operation. <Ref. to AB-5,

CAUTION, General Description.>

19) Connect the ground cable to battery.
CAUTION:

After completion of installation, adjust the fol-

lowing two positions.

• Positioning to the center of steering angle

sensor

• Positioning the yaw rate & G sensors to zero

The above procedure is required for the VDC-

CM to identify vehicle position afterward. For

the setting procedures of the 2 steps above, re-

fer to “Adjustment” in “VDC Control Module &

Hydraulic Control Unit (VDCCM&H/U)”. <Ref. to

VDC-13, ADJUSTMENT, VDC Control Module

and Hydraulic Control Unit (VDCCM&H/U).>

(1) Protrusion portion
(2) Inspection hole
(3) Alignment mark

(1) Grease application location

VDC00209

(1)

(2)

(3)

ABS00435

(1)

VDC00885

AB-02604

VDC-24

Front ABS Wheel Speed Sensor

VEHICLE DYNAMICS CONTROL (VDC)

8. Front ABS Wheel Speed Sen-

sor

A: REMOVAL

1) Disconnect the ground cable from battery.

2) Disconnect the ABS wheel speed sensor con-

nector located next to the front strut mounting

house in the engine compartment.

3) Remove the bolts and then remove the sensor

harness bracket.

4) Remove the bolts which secure the sensor har-

ness to the front strut.

5) Remove the bolts, and remove the front ABS

wheel speed sensor from the front housing.
CAUTION:

• Be careful not to damage the sensor.

• Do not apply excessive force to the sensor

harness.

B: INSTALLATION

CAUTION:

Be careful not to damage the sensor.

Install each part in the reverse order of removal.
Tightening torque:

Sensor:

7.5 N·m (0.76 kgf-m, 5.5 ft-lb)

Bracket:

33 N·m (3.36 kgf-m, 24.3 ft-lb)

NOTE:

• Check the identification (mark) on the harness to

make sure there is no warpage. (RH: K1 (White),

LH: K2 (Yellow))

• Check if the harness is not pulled and does not

come in contact with the suspension or body during

steering wheel effort.

C: INSPECTION

1. CHECK WITH SUBARU SELECT MONI-

TOR

1) Connect the Subaru Select Monitor to the data

link connector.

2) Select {Current Data Display & Save}. Check if

the speed indicated on the display changes in the

same manner as the speedometer reading during

acceleration/deceleration when the steering wheel

is in the straight-ahead position.

3) If the speed indicated on the display does not

change, check the ABS wheel speed sensor. <Ref.

to VDC-25, ABS WHEEL SPEED SENSOR, IN-

SPECTION, Front ABS Wheel Speed Sensor.>

(1) To the front ABS wheel speed sensor connector
(2) Sensor harness bracket

ABS00386

(1)

(2)

ABS00387