Subaru Legacy III (2000-2003 year). Service manual — part 738

VDC-20

VDC

VDC SEQUENCE CONTROL

3. CONDITIONS FOR VDC SEQUENCE CONTROL

NOTE:
• When select monitor is used, control operation starts at point A. The patterns from IGN key ON to the point
A show that operation is started by diagnosis connector.
• HIGH means high voltage.
• LOW means low voltage.

VDC00087

Speed of all wheels

Terminal No. 5 and No. 8

Ignition key switch

ABS warning light

VDC warning light

VDC. OFF indicator light

Pressure sensor signal

AET

AEB

AEC

EAM

Valve relay

Secondary cut valve

Primary cut valve

Secondary suction valve

Primary suction valve

FL outlet valve

FL inlet valve

FR outlet valve

FR inlet valve

RR outlet valve

RR inlet valve

RL outlet valve

RL inlet valve

Pump motor

Pressure of master cylinder

Pressure of RL wheel cylinder

Pressure of FL wheel cylinder

Pressure of RR wheel cylinder

Pressure of FR wheel cylinder

VDC operation indicator light

Operational
guide line of
sequence
control

Operational
pattern of
sequence
control

Operational
pressure of
sequence
control

2.75 km/h (2 MPH) or less

LOW

OFF

OFF

LIGHT

Within 0.5s

Point A

OFF

OFF

OFF

OFF

LIGHT

LIGHT

LIGHT

LOW

HIGH

LOW

HIGH

LOW

HIGH

LOW

HIGH

OFF

OFF

ON

OFF

ON

OFF

ON

OFF

ON

OFF

ON

OFF

ON

OFF

ON

OFF

ON

OFF

ON

OFF

ON

OFF

ON

OFF

ON

OFF

ON

ON

1.5s

1s

10 km/h (6 MPH) or less

ON (Engine run)

0.8s

Within 0.4s

Within 3s

0.4s

1.6s

1.6s

1s

3.4s

3.4s

ON

VDC-21

VDC

VDC SEQUENCE CONTROL

B: SPECIFICATION

1. CONDITIONS FOR COMPLETION OF
VDC SEQUENCE CONTROL

When the following conditions develop, the VDC
sequence control stops and VDC operation is re-
turned to the normal control mode.
1) When the speed of at least one wheel reaches
10 km/h (6 MPH).
2) When terminal No. 5 or No. 8 are separated from
diagnosis terminals. (When select monitor is not
used.)
3) When the brake pedal is pressed during se-
quence control and the braking lamp switch is set
to on.
4) When brake pedal is depressed after ignition key
is turned to ON, and before VDC warning light goes
out. (When select monitor is not used.)
5) When brake pedal is not depressed after ignition
key is turned to ON, and within 0.5 seconds after
VDC warning light goes out. (When select monitor
is not used.)
6) After completion of the sequence control.
7) When malfunction is detected. (When select
monitor is used.)

VDC-22

VDC

YAW RATE AND LATERAL G SENSOR

6. Yaw Rate and Lateral G Sen-

sor

A: REMOVAL

1) Disconnect battery ground cable.

2) Remove console cover.
<Ref. to EI-34, Console Box.>
3) Disconnect connector from yaw rate and lateral
G sensor.
4) Remove yaw rate and lateral G sensor.

CAUTION:
Do not drop or bump yaw rate and lateral G sen-
sor.

5) Remove bracket from body.

B: INSTALLATION

Install in the reverse order of removal.

NOTE:
Do not install yaw rate and lateral G sensor in the
wrong direction. There is an arrow on the sensor
showing which side faces the front of the vehicle.

CAUTION:
After completion of installation procedure, the
following two position settings must be made.
• Steering angle sensor center positioning
• Yaw rate and lateral G sensor 0 positioning
These procedures are necessary for VDCCM to
later recognize what position the vehicle is in.
For procedures for the above two settings,
<Ref. to VDC-9, ADJUSTMENT, VDC Control
Module (VDCCM).>.

FU-00009

VDC00088

VDC00089

VDC00090

VDC-23

VDC

YAW RATE AND LATERAL G SENSOR

C: INSPECTION

1. LATERAL G SENSOR SIGNAL

Step

Value

Yes

No

1

CHECK SUBARU SELECT MONITOR.

Do you have SUBARU select
Monitor?

Go to step 5.

Go to step 2.

2

CHECK YAW RATE AND LATERAL G SEN-
SOR.
1) Move the vehicle to a flat location.
2) Turn ignition switch to OFF.
3) Connect connector to yaw rate and lateral

G sensor.

4) Turn ignition switch to ON.
5) Measure voltage between yaw rate and lat-

eral G sensor connector terminals.

Connector & terminal

(R100) No. 5 (+) — No. 6 (

−−−−

)

Is the voltage within the specified range
when yaw rate and lateral G sensor is hori-
zontal?

2.5

±

0.2 V

Go to step 3.

Replace yaw rate
and lateral G sen-
sor.

3

CHECK YAW RATE AND LATERAL G SEN-
SOR.
1) Remove yaw rate and lateral G sensor from

vehicle.

2) Measure voltage between yaw rate and lat-

eral G sensor connector terminals.

Connector & terminal

(R100) No. 5 (+) — No. 6 (

−−−−

)

NOTE:

If the yaw rate and lateral G sensor is moved,
the VDC (Yaw rate sensor) may be stored into
the memory.

Is the voltage within the specified range
when yaw rate and lateral G sensor is
inclined right to 90

°

?

3.5

±

0.2 V

Go to step 4.

Replace yaw rate
and lateral G sen-
sor.

4

CHECK YAW RATE AND LATERAL G SEN-
SOR.
Measure voltage between yaw rate and lateral
G sensor connector terminals.

Connector & terminal

(R100) No. 5 (+) — No. 6 (

−−−−

)

NOTE:

If the yaw rate and lateral G sensor is moved,
the VDC (Yaw rate sensor) may be stored into
the memory.

Is the voltage within the specified range when
yaw rate and lateral G sensor is inclined left to
90

°

?

1.5

±

0.2 V

Go to step 5.

Replace yaw rate
and lateral G sen-
sor.