
VDC(diag)-44
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)
Step Check Yes No
1CHECK THE VDCCM&H/U POWER SUPPLY
CIRCUIT.
1) Turn the ignition switch to OFF.
2) Disconnect the VDCCM&H/U connector.
3) Turn the ignition switch to ON.
4) Measure the voltage between VDCCM&H/
U connector terminals.
Connector & terminal
(B310) No. 1 (+) — (B310) No. 43 (–):
Is the voltage 10 — 15 V? Go to step 2.Check the genera-
tor, batter y and
VDCCM&H/U
power supply cir-
cuit.
2CHECK OUTPUT OF ABS WHEEL SPEED
SENSOR USING SUBARU SELECT MONI-
TOR.
1) Select {Current Data Display & Save} in
Subaru Select Monitor.
2) Read the ABS wheel speed sensor output
corresponding to the faulty wheel in Subaru
Select Monitor data display mode.
Does the speed indicated on
the display change in response
to the speedometer reading
during acceleration/decelera-
tion when the steering wheel is
in the straight-ahead position?
Go to step 3.Go to step 8.
3CHECK POOR CONTACT IN CONNECTOR.
Tu r n t h e i g n i t i o n s w i t c h t o O F F.
Is there poor contact in con-
nectors between VDCCM&H/U
and ABS wheel speed sensor?
Repair the con-
nector.
Go to step 4.
4CHECK CAUSE OF SIGNAL NOISE.
Make sure the radio wave devices and electric
components are installed correctly.
Are the radio wave devices and
electric components installed
correctly?
Go to step 5.Install the radio
wave devices and
electric compo-
nents properly.
5CHECK CAUSE OF SIGNAL NOISE.
Check if the noise sources (such as an
antenna) are installed near the sensor har-
ness.
Are noise sources installed? Install the noise
sources apart from
sensor harness.
Go to step 6.
6CHECK THE VDCCM&H/U.
1) Connect all the connectors.
2) Erase the memory.
3) Perform the inspection mode.
Mode.>
4) Read the DTC.
Is the same DTC displayed? Replace the
VDCCM&H/U.
ule & Hydraulic
Control Unit
(VDCCM&H/U).>
Go to step 7.
7CHECK OTHER DTC DETECTION.Is any other DTC displayed? Perform the diag-
nosis according to
DTC.
It results from a
temporary noise
interference.
8CHECK INSTALLATION OF ABS WHEEL
SPEED SENSOR.
Is the ABS wheel speed sen-
sor installation bolt tightened
7.5 N·m (0.76 kgf-m, 5.5 ft-lb)?
Go to step 9.Tighten the ABS
wheel speed sen-
sor installation
bolts.
9CHECK ABS WHEEL SPEED SENSOR SIG-
NAL.
1) Install the ABS wheel speed sensor.
2) Prepare an oscilloscope.
3) Check the ABS wheel speed sensor.
INSPECTION, Front ABS Wheel Speed Sen-
sor.>
Does the oscilloscope indicate
the waveform pattern like
shown in the figure when the
tire is slowly turned? Does the
oscilloscope indication repeat
the waveform pattern like
shown in the figure when the
tire is slowly turned in equal
speed for more one rotation?
Go to step 11.Go to step 10.

VDC(diag)-45
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)
M: DTC C0031 FRONT INLET SOLENOID VALVE RH MALFUNCTION IN VDC-
CM&H/U
NOTE:
For the diagnostic procedure, refer to DTC C0063 “LINEAR VALVE MALFUNCTION IN VDCCM&H/U”.
N: DTC C0032 FRONT OUTLET SOLENOID VALVE RH MALFUNCTION IN VDC-
CM&H/U
NOTE:
For the diagnostic procedure, refer to DTC C0063 “LINEAR VALVE MALFUNCTION IN VDCCM&H/U”.
10 CHECK ABS WHEEL SPEED SENSOR OR
MAGNETIC ENCODER.
Are there foreign matter,
breakage or damage at the tip
of ABS wheel speed sensor or
magnetic encoder?
Remove dirt
throughly. Also
replace the ABS
wheel speed sen-
sor or magnetic
encoder as a unit
with hub unit bear-
ing if it is broken or
damaged.
Go to step 11.
11 CHECK CAUSE OF SIGNAL NOISE.
Make sure the radio wave devices and electric
components are installed correctly.
Are the radio wave devices and
electric components installed
correctly?
Go to step 12.Install the radio
wave devices and
electric compo-
nents properly.
12 CHECK CAUSE OF SIGNAL NOISE.
Check if the noise sources (such as an
antenna) are installed near the sensor har-
ness.
Is the noise sources installed? Go to step 13.Install the noise
sources apart from
sensor harness.
13 CHECK THE VDCCM&H/U.
1) Connect all the connectors.
2) Erase the memory.
3) Perform the inspection mode.
Mode.>
4) Read the DTC.
Is the same DTC displayed? Replace the
VDCCM&H/U.
ule & Hydraulic
Control Unit
(VDCCM&H/U).>
Go to step 14.
14 CHECK OTHER DTC DETECTION.Is any other DTC displayed? Perform the diag-
nosis according to
DTC.
It results from a
temporary noise
interference.
NOTE:
Though the ABS
warning light re-
mains on at this
time, it is normal.
Drive the vehicle at
more than 12 km/h
(7 MPH) in order to
turn ABS warning
light off. Be sure to
drive the vehicle
and check the
warning light goes
off.
Step Check Yes No

VDC(diag)-77
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)
AQ:DTC C0071 STEERING ANGLE SENSOR SIGNAL SEIZURE
DTC DETECTING CONDITION:
Defective steering angle sensor
TROUBLE SYMPTOM:
VDC does not operate.
AR:DTC C0071 STEERING ANGLE SENSOR CALIBRATION INCOMPLETE
DTC DETECTING CONDITION:
Steering angle sensor calibration is incomplete.
TROUBLE SYMPTOM:
VDC does not operate.
Calibrate the steering angle sensor.
AS:DTC C0072 YAW RATE SENSOR OSCILLATION MALFUNCTION
NOTE:
For the diagnostic procedure, refer to DTC C0072 “YAW RATE SENSOR SIGNAL MALFUNCTION”.
Diagnostic Trouble Code (DTC).>
Step Check Yes No
1CHECK STEERING WHEEL.
1) Drive the vehicle on a flat road.
2) Park the vehicle straight.
3) Check the steering wheel for deviation from
center.
Is the deviation from the center
of steering wheel less than 5°?
Go to step 2.Perform the cen-
tering adjustment
of steering wheel.
2CHECK 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 3.
3CHECK OUTPUT OF STEERING ANGLE
SENSOR WITH SUBARU SELECT MONI-
TOR.
1) Select {Current Data Display & Save} in
Subaru Select Monitor.
2) Read the steering angle sensor output dis-
played on display.
Does the steering angle sensor
output value on the display
var y in accordance with steer-
ing operation when turning the
steering wheel to the right or
left?
Go to step 4.Replace the steer-
ing angle sensor.
4CHECK THE VDCCM&H/U.
1) Turn the ignition switch to OFF.
2) Connect all the connectors.
3) Erase the memory.
4) Perform the inspection mode.
5) Read the DTC.
Is the same DTC displayed? Replace the
VDCCM&H/U.
ule & Hydraulic
Control Unit
(VDCCM&H/U).>
Go to step 5.
5CHECK OTHER DTC DETECTION.Is any other DTC displayed? Perform the diag-
nosis according to
DTC.
Te m p o r a r y p o o r
contact occurs.

VDC(diag)-87
General Diagnostic Table
VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)
13.General Diagnostic Table
A: INSPECTION
Symptom Main probable cause Other probable cause
Po or b rake pe r -
for mance
Long braking/
stopping dis-
tance
•VDCCM&H/U
•Brake pad
•Aeration to brake line
•Tire specifications, tire wear and air pressures
•Incorrect wiring or piping connections
•Defective ABS wheel speed sensor or
sensor gap
•Defective steering angle sensor or
improper neutral position
•Defective yaw rate & G sensor or
improper installation
•Master cylinder
•Brake caliper
•Disc rotor
•Brake pipe
•Brake booster
Wheel lock • VDCCM&H/U
•Defective ABS wheel speed sensor or sensor
gap
•Incorrect wiring or piping connections
•Defective steering angle sensor or
improper neutral position
•Defective yaw rate & G sensor or
improper installation
•Brake caliper
•Brake pipe
Brake drag • VDCCM&H/U
•Defective ABS wheel speed sensor or sensor
gap
•Master cylinder
•Brake caliper
•Parking brake
•Axle and wheels
•Brake pedal play
•Defective steering angle sensor or
improper neutral position
•Defective yaw rate & G sensor or
improper installation
•Brake pad
•Brake pipe
Long brake
pedal stroke
•Aeration to brake line
•Brake pedal play
•VDCCM&H/U
•Master cylinder
•Brake caliper
•Brake pad
•Brake pipe
•Brake booster
Ve h i c l e v e r t i -
cal pitching
•VDCCM&H/U
•Road surface (uneven)
•Suspension play or fatigue (reduced damping)
•Incorrect wiring or piping connections
•Defective ABS wheel speed sensor or
sensor gap
•Defective steering angle sensor or
improper neutral position
•Defective yaw rate & G sensor or
improper installation
Po or b rake pe r -
for mance
Unstable or
uneven brak-
ing
•VDCCM&H/U
•Defective ABS wheel speed sensor or sensor
gap
•Brake caliper
•Brake pad
•Road surface (uneven)
•Tire specifications, tire wear and air pressures
•Incorrect wiring or piping connections
•Defective ABS wheel speed sensor or
sensor gap
•Defective steering angle sensor or
improper neutral position
•Defective yaw rate & G sensor or
improper installation
•Master cylinder
•Disc rotor
•Brake pipe
•Axle and wheels
•Road with crowns or banks
•Suspension play or fatigue (poor damp-
ing)

VDC(diag)-88
General Diagnostic Table
VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)
Vibration or
noise
•When braking
suddenly
•When acceler-
ating suddenly
•While driving
on a slippery
road
Excessive
brake pedal
vibration
•Road surface (uneven)
•Incorrect wiring or piping connections
•VDCCM&H/U
•Brake booster
•Suspension play or fatigue (poor damp-
ing)
Noise from
VDCH/U
•VDCCM&H/U (mount bushing)
•Defective ABS wheel speed sensor or sensor
gap
•Brake pipe
•VDCCM&H/U
•Defective steering angle sensor or
improper neutral position
•Defective yaw rate & G sensor or
improper installation
Noise from
the front side
of vehicle
•VDCCM&H/U (mount bushing)
•Defective ABS wheel speed sensor or sensor
gap
•Master cylinder
•Brake caliper
•Brake pad
•Disc rotor
•Brake pipe
•Brake booster
•Suspension play or fatigue (poor damping)
•Axle and wheels
•Tire specifications, tire wear and air
pressures
Noise inside
passenger
seat
•VDCCM&H/U
•Defective steering angle sensor or
improper neutral position
•Defective yaw rate & G sensor or
improper installation
Noise from
the rear side
of vehicle
•Defective ABS wheel speed sensor or sensor
gap
•Brake caliper
•Brake pad
•Disc rotor
•Parking brake
•Brake pipe
•Suspension play or fatigue (poor damping)
•Axle and wheels
•Tire specifications, tire wear and air
pressures
Engine does not accelerate or
goes into a stall when accelerat-
ing suddenly or driving on a slip-
pery surface.
•VDCCM&H/U
•Defective ABS wheel speed sensor or sensor
gap
•Master cylinder
•Brake caliper
•Parking brake
•Incorrect wiring or piping
•Defective steering angle sensor or
improper neutral position
•Defective yaw rate & G sensor or
improper installation
•Brake pad
•Brake pipe
Symptom Main probable cause Other probable cause

VDC(diag)-89
General Diagnostic Table
VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)
Po or ch a ng e -
direction-opera-
tion stability of
TCS
Deviation to
right or left
direction
•VDCCM&H/U
•Defective ABS wheel speed sensor or sensor
gap
•Defective steering angle sensor or improper
neutral position
•Defective yaw rate & G sensor or improper
installation
•Brake caliper
•Brake pad
•Wheel alignment
•Road surface (uneven)
•Road with crowns or banks
•Tire specifications, tire wear and air pressures
•Incorrect wiring or piping connections
•Disc rotor
•Brake pipe
•Axle and wheels
•Suspension play or fatigue (poor damp-
ing)
Ve h i c l e s p i n • V D C C M & H / U
•Defective ABS wheel speed sensor or sensor
gap
•Defective steering angle sensor or improper
neutral position
•Defective yaw rate & G sensor or improper
installation
•Brake pad
•Tire specifications, tire wear and air pressures
•Incorrect wiring or piping connections
•Brake caliper
•Brake pipe
Steering wheel drag while driving • VDCCM&H/U
•Defective ABS wheel speed sensor or sensor
gap
•Defective steering angle sensor or improper
neutral position
•Defective yaw rate & G sensor or improper
installation
•Incorrect wiring or piping connections
•Power steering system
•Brake caliper
•Brake pad
•Disc rotor
•Wheel alignment
•Road surface (uneven)
•Road with crowns or banks
•Suspension play or fatigue (poor damp-
ing)
•Tire specifications, tire wear and air
pressures
VDC operates while driving nor-
mally.
•VDCCM&H/U
•Defective ABS wheel speed sensor or sensor
gap
•Defective steering angle sensor or improper
neutral position
•Defective yaw rate & G sensor or improper
installation
•Wheel alignment
•Road surface (uneven)
•Road with crowns or banks
•Suspension play or fatigue (poor damping)
•Tire specifications, tire wear and air pressures
•Incorrect wiring or piping connections
•Power steering system
TCS OFF indicator light does not
come on when the TCS OFF
switch is depressed.
NOTE:When pressing TCS OFF switch
for more than 10 seconds, TCS
OFF indicator light goes off and
cannot operate any more. When
turning the ignition switch from
OFF to ON, the previous status is
restored.
•Harness
•Indicator light bulb
•TCS OFF switch
Symptom Main probable cause Other probable cause

VDC-2
General Description
VEHICLE DYNAMICS CONTROL (VDC)
1. General Description
A: SPECIFICATION
B: COMPONENT
1. ABS WHEEL SPEED SENSOR
Item Specification or identification
ABS wheel speed
sensor
ABS wheel speed sensor
gap (for reference)
Fr o nt 0 . 55 — 1. 4 5 m m ( 0. 0 2 2 — 0. 0 57 i n)
Rear 0.50 — 1.50 mm (0.020 — 0.059 in)
Identifications of harness
(marks, color)
Fr o nt W1 ( Wh i te )
Rear W3 (White)
VDCCM&H/U IdentificationW1
(1) Front ABS wheel speed sensor (4) Hub unit bearingTightening torque: N·m (kgf-m, ft-lb)
(2) Front housing (5) Magnetic encoderT: 7.5 (0.76, 5.5)
(3) Rear ABS wheel speed sensor
VDC00340
T
T
(3)
(4)
(5)
(2)
(1)

VDC-8
VDC Control Module & Hydraulic Control Unit (VDCCM&H/U)
VEHICLE DYNAMICS CONTROL (VDC)
4) Connect the VDCCM&H/U connectors.
NOTE:
•Be sure to remove all foreign matter from inside
the connector before connecting.
•Make sure the VDCCM&H/U connector is se-
curely locked.
5) Bleed air from the brake system.
C: INSPECTION
1) Check the condition of connection and settle-
ment of connector.
2) Check the mark used for VDCCM&H/U identifi-
cation.
Refer to “SPECIFICATION” for the identification
mark.
1. CHECKING THE HYDRAULIC UNIT ABS
OPERATION BY PRESSURE GAUGE
1) Lift-up the vehicle and remove the wheel.
2) Remove the air bleeder screws from FL and FR
caliper bodies.
3) Connect two pressure gauges to FL and FR cal-
iper bodies.
CAUTION:
•Use a pressure gauge used exclusively for
brake fluid measurement.
•Do not use the pressure gauge used for the
measurement of transmission oil. Doing so will
cause the piston seal to expand and deform.
NOTE:
Wrap sealing tape around the pressure gauge.
4) Bleed air from the pressure gauges and the FL
and FR caliper bodies.
5) Perform ABS sequence control.
6) When the hydraulic unit begins to work, first the
FL side performs decompression, hold and com-
pression, and then the FR side performs decom-
pression, hold and compression.
7) Read values indicated on the pressure gauge
and check if the fluctuation of the values between
decompression and compression meets the stan-
dard values. Depress the brake pedal and check
that the kick-back is normal, and tightness is nor-
mal.
8) Disconnect the pressure gauges from FL and FR
caliper bodies.
9) Install the air bleeder screws of FL and FR cali-
per bodies.
10) Remove the air bleeder screws from RL and
RR caliper bodies.
11) Connect two pressure gauges to RL and RR
caliper bodies.
(1) Identification mark
VDC00345
(1)
Front wheelRear wheel
Initial value
3,500 kPa
(36 kgf/cm2, 511
psi)
3,500 kPa
(36 kgf/cm2, 511
psi)
When depres-
surized
500 kPa
(5 kgf/cm2, 73 psi)
or less
500 kPa
(5 kgf/cm2, 73 psi)
or less
When pressur-
ized
3,500 kPa
(36 kgf/cm2, 511
psi)
or more
3,500 kPa
(36 kgf/cm2, 511
psi)
or more
ABS00134