2012 SUBARU IMPREZA WRX STI traction control

Black plate (268,1)
北米Model "A1130BE-A" EDITED: 2011/ 6/ 7
7-18
Starting and operating
Driver ’s Control Center Dif-
ferential (DCCD) (STI)
WARNING
Always use the utmost care when
driving. Being overconfident be-
cause you are driving a vehicle with
a driver ’s control center differential
could easily lead to a serious acci-
dent.
CAUTION
All the indicator lights will flash in
the event that the driver ’s control
center differential has a malfunc-
tion. Have the vehicle inspected by
your SUBARU dealer.
The driver ’s control center differential
allows you to freely change the degree
of limitation of the differential action
(limited slip differential (LSD) torque) of
your vehicle ’s center differential.
By using the center differential control
switch, you can set an initial LSD torque to
match the road surface conditions, driving
conditions and your driving style.
1) LSD torque
2) Traction torque
3) Initial LSD torque (maximum)
4) Initial LSD torque (minimum)
A) Initial LSD torque (adjustable)
B) Mechanical LSD torqueThe driver ’s control center differential has
an auto mode and a manual mode. In the
auto mode, the system automatically
adjusts the initial LSD torque. In the
manual mode, you can change to the
desired mode manually by using the
center differential control switch.NOTEIf you rapidly depress and release the
accelerator pedal while driving at low
speed, you may hear a knocking sound
from the vicinity of the center differen- tial and rear differential. This sound
occurs because of the structure of the
center differential. It does not indicate a
problem.
&
To change mode of driver ’s
control center differentialPress the “AUTO-MANU ”switch on the
center console to switch from auto mode
to manual mode or vice versa. When you
select the auto mode, the “AUTO”indica-
tor light illuminates. When you select the
manual mode, the “AUTO”indicator light
turns off.

Black plate (269,1)
北米Model "A1130BE-A" EDITED: 2011/ 6/ 7
& Auto modeIn the auto mode, the system estimates
the driving and road conditions using
signals from the wheel speed sensor,
throttle position sensor, steering angle
sensor and brake switch, etc. According
to the result, it electronically and auto-
matically controls the degree of limitation
of the differential action (LSD torque) to
optimize the differential action of the
center differential. When the ignition
switch is turned ON, the “AUTO”indicator
light on the combination meter illuminates. The auto mode has 3 modes as follows.
Mode
Operation
AUTO [+] This mode emphasizes traction control and strengthens the
limitation of differential action
that is suitable for driving on
slippery roads for vehicle stabi-
lity.
AUTO This mode is suitable for most driving situations.
AUTO [] This mode is suitable when you seek quick response from the
steering wheel and smooth
driving.
!Mode setting method
In most situations, it is recommended that
the “AUTO ”mode is selected.Push the control switch forward to select the
“AUTO [+] ”mode. After setting the
mode, “
”on the combination meter
illuminates.
Pull the control switch rearward to select
the “AUTO [ ]” mode. After setting the
mode, “
”on the combination meter
illuminates.
When the “AUTO [+]”mode is selected,
pull the control switch rearward to change
to the “AUTO”mode. When the “AUTO
[ ]” mode is set, push the control switch
forward to change to the “AUTO”mode.
Starting and operating
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Black plate (271,1)
北米Model "A1130BE-A" EDITED: 2011/ 6/ 7
Pull the switch rearward to reduce the
initial LSD torque. When the lowest posi-
tion of the driver ’s control center differen-
tial indicator light illuminates, the initial
LSD torque will be minimum. Under this
condition, only the Mechanical LSD torque
will limit the differential action.
CAUTION
. Do not operate the control switch
when a wheel slippage occurs.
Wait until the wheelspin has been
brought under control.
. Under any of the following con-
ditions after setting to the man-
ual mode, pull the center differ-
ential control switch to minimize
the initial LSD torque: .
When a temporary spare tire is
installed
. When your vehicle is towed
. When the vehicle is stopped
with the manual mode se-
lected
NOTE. A higher initial LSD torque setting
gives the vehicle greater traction when
driving straight ahead but makes cor-
nering more difficult. Remember this
when adjusting the initial LSD torque.
In general, higher initial LSD torque
settings assist driving on slippery
roads and lower settings for non-slip-
pery roads. When the vehicle is stuck
in snow or mud, setting the initial LSD
torque to the maximum will help to free
the vehicle.
. The setting of the initial LSD torque
will remain even when the auto mode is
selected or the ignition switch is turned
to the “LOCK ”position. However, the
initial LSD torque will be minimized
when the battery is disconnected and
reconnected.
. During cornering or when making
turns (especially when going into the
garage), the rotational difference be-
tween the front and rear wheels may cause a braking effect accompanied by
vibration and noise. This does not
indicate a problem. The phenomenon
will disappear when setting the initial
LSD torque to the minimum.
In the auto mode, it controls the initial
LSD torque automatically. While in the
auto mode, this phenomenon some-
times occurs depending on the driving
condition, however, it does not indicate
a problem.
.
Use the center differential indicator
light only as a rough indication of the
initial LSD torque.
. If you operate the center differential
control switch while quickly accelerat-
ing or turning a tight corner, you may
feel slight shocks. This is due to
differential action by the center differ-
ential and does not indicate a problem.
& Temporary releaseWhen the driver stops the vehicle and
pulls the parking brake lever after manu-
ally setting the initial LSD torque, the LSD
torque is temporarily minimized. However
the indicator on the combination meter
continues to show the driver ’s selected
initial LSD torque. When the driver re-
leases the parking brake lever, the initial
LSD torque set by the driver is restored.
Starting and operating
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7

Black plate (278,1)
北米Model "A1130BE-A" EDITED: 2011/ 6/ 7
7-28
Starting and operating
Vehicle Dynamics Control
system
WARNING
Always use the utmost care in
driving –overconfidence because
you are driving with a Vehicle Dy-
namics Control system equipped
vehicle could easily lead to a ser-
ious accident.
CAUTION
. Even if your vehicle is equipped
with Vehicle Dynamics Control
system, winter tires should be
used when driving on snow-cov-
ered or icy roads; in addition,
vehicle speed should be reduced
considerably. Simply having a
Vehicle Dynamics Control sys-
tem does not guarantee that the
vehicle will be able to avoid
accidents in any situation.
. Activation of the Vehicle Dy-
namics Control system is an
indication that the road being
travelled on has a slippery sur-
face; since having Vehicle Dy-
namics Control is no guarantee that full vehicle control will be
maintained at all times and under
all conditions, its activation
should be seen as a sign that
the speed of the vehicle should
be reduced considerably.
. Whenever suspension compo-
nents, steering components, or
an axle are removed from a
vehicle, have an inspection of
that system performed by an
authorized SUBARU dealer.
. The following precautions should
be observed in order to ensure
that the Vehicle Dynamics Con-
trol system is operating properly:
– All four wheels should be
fitted with tires of the same
size, type, and brand. Further-
more, the amount of wear
should be the same for all
four tires.
– Keep the tire pressure at the
proper level as shown on the
vehicle placard attached to
the driver ’s side door pillar.
– Use only the specified tem-
porary spare tire to replace a
flat tire. With a temporary
spare tire, the effectiveness
of the Vehicle Dynamics Con- trol system is reduced and
this should be taken into ac-
count when driving the vehi-
cle in such a condition.
. If non-matching tires are used,
the Vehicle Dynamics Control
system may not operate cor-
rectly.
. The Vehicle Dynamics Control
system helps prevent unstable
vehicle motion such as skidding
using control of the brakes and
engine power. Do not turn off the
Vehicle Dynamics Control sys-
tem unless it is absolutely ne-
cessary. If you must turn off the
Vehicle Dynamics Control sys-
tem, drive very carefully based
on the road surface condition.
In the event of wheelspin and/or skidding
on a slippery road surface and/or during
cornering and/or an evasive maneuver,
the Vehicle Dynamics Control system
adjusts the engine ’s output and the
wheels ’respective braking forces to help
maintain traction and directional control.
. Traction Control Function
The traction control function is designed to
prevent spinning of the driving wheels on
slippery road surfaces, thereby helping to
maintain traction and directional control.

Black plate (279,1)
北米Model "A1130BE-A" EDITED: 2011/ 6/ 7
Activation of this function is indicated by
steady illumination of the Vehicle Dy-
namics Control operation indicator light.
. Skid Suppression Function
The skid suppression function is designed
to help maintain directional stability by
suppressing the wheels ’tendency to slide
sideways during steering operations. Acti-
vation of this function is indicated by
flashing of the Vehicle Dynamics Control
operation indicator light.NOTE. The Vehicle Dynamics Control sys-
tem may be considered normal when
the following conditions occur.
–Slight twitching of the brake
pedal is felt.
– The vehicle or steering wheel
shakes to a small degree.
– An operating sound from the
engine compartment is heard
briefly when starting the engine
and when driving off after starting
the engine.
– The brake pedal seems to jolt
when driving off after starting the
engine.
. In the following circumstances, the
vehicle may be less stable than it feels
to the driver. The Vehicle Dynamics Control System may therefore operate.
Such operation does not indicate a
system malfunction.
–on gravel-covered or rutted
roads
– on unfinished roads
– when the vehicle is fitted with
snow tires or winter tires
. Activation of the Vehicle Dynamics
Control system will cause operation of
the steering wheel to feel slightly
different compared to that for normal
conditions.
. It is always important to reduce
speed when appro aching a corner,
even if the vehicle is equipped with
Vehicle Dynamics Control.
. Always turn off the engine before
replacing a tire as failure to do so may
render the Vehicle Dynamics Control
system unable to operate correctly.
& Vehicle Dynamics Control
system monitorRefer to “Vehicle Dynamics Control warn-
ing light/Vehicle Dynamics Control opera-
tion indicator light ”F 3-20 and “Vehicle
Dynamics Control OFF indicator light/
Traction Control OFF indicator light (STI) ”
F 3-21.
& Vehicle Dynamics Control
mode switch (STI)Indicator lightVehicle Dynamics Control mode switchWhen the switch is pressed briefly or for
more than approximately 3 seconds dur-
Starting and operating
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Black plate (280,1)
北米Model "A1130BE-A" EDITED: 2011/ 6/ 7
7-30
Starting and operating
ing engine operation, the mode of the
Vehicle Dynamics Control System will be
changed.
! Vehicle Dynamics Control mode
When the ignition switch is on, this mode
is selected.
This mode enables all controls for ABS,
the Traction Control System, and the
Vehicle Dynamics Control system. Select
this mode for most driving situations.
When this mode is selected, the indicator
light on the combination meter turns off.
! Traction mode
This mode restricts the functions of the
Traction Control System and Vehicle
Dynamics Control system and thus delays
utilizing their functions as a reaction to
vehicle behavior in comparison with the
Vehicle Dynamics Control mode. This
mode should be used in driving situations
where the vehicle dynamic performance
will improve without decreasing engine
torque control.
When the switch is pressed briefly during
engine operation, the indicator light on the
combination meter illuminates in green.
When the switch is pressed again to
reactivate the Vehicle Dynamics Control
system, the indicator light turns off. !
Vehicle Dynamics Control OFF
mode
This mode allows only the ABS control.
This mode should be used in an emer-
gency situation such as getting out of
snow or mud.
When the switch is pressed for more than
approximately 3 seconds during engine
operation, the indicator light on the com-
bination meter illuminates in yellow. When
the switch is pressed again to reactivate
the Vehicle Dynamics Control system, the
indicator light turns off.
NOTE. The Vehicle Dynamics Control sys-
tem will be activated automatically
when the engine is started.
. If the switch is held down for 10
seconds or longer, the indicator light
turns off, the Vehicle Dynamics Control
system is activated, and the system
ignores any further pressing of the
switch. To make the switch usable
again, turn the ignition switch to the
“ LOCK ”position and restart the en-
gine.
. When the Vehicle Dynamics Control
OFF mode is selected, the vehicle ’s
running performan ce is comparable
with that of a vehicle that does not
have a Vehicle Dynamics Control sys- tem. Do not deactivate the Vehicle
Dynamics Control system except when
absolutely necessary.
.
Even when the Vehicle Dynamics
Control OFF mode is selected, compo-
nents of the brake control system may
still activate. When the brake control
system is activated, the Vehicle Dy-
namics Control operation indicator
light illuminates.
& Vehicle Dynamics Control
OFF switch (except STI)Indicator light

Black plate (281,1)
北米Model "A1130BE-A" EDITED: 2011/ 6/ 7
Vehicle Dynamics Control OFF switchPressingtheswitchtodeactivatethe
Vehicle Dynamics Control system can
facilitate the following operations:
. a standing start on a steeply sloping
road with a snowy, gravel-covered, or
otherwise slippery surface
. extrication of the vehicle when its
wheels are stuck in mud or deep snow
When the switch is pressed during engine
operation, the Vehicle Dynamics Control
OFF indicator light on the combination
meter illuminates. The Vehicle Dynamics
Control system will be deactivated and the
vehicle will behave like a model not
equipped with the Vehicle Dynamics Con-
trol system. When the switch is pressed
again to reactivate the Vehicle Dynamics Control system, the Vehicle Dynamics
Control OFF indicator light turns off.
With the Vehicle Dynamics Control system
deactivated, traction and stability en-
hancement offered by Vehicle Dynamics
Control system is unavailable. Therefore
you should not deactivate the Vehicle
Dynamics Control system except under
above-mentioned situations.
NOTE.
The Vehicle Dynamics Control sys-
tem will be activated automatically
when the engine is started.
. If the switch is held down for 10
seconds or longer, the indicator light
turns off, the Vehicle Dynamics Control
system is activated, and the system
ignores any further pressing of the
switch. To make the switch usable
again, turn the ignition switch to the
“ LOCK ”position and restart the en-
gine.
. When the switch is pressed to
deactivate the Vehicle Dynamics Con-
trol system, the vehicle ’s running per-
formance is comparable with that of a
vehicle that does not have a Vehicle
Dynamics Control system. Do not de-
activate the Vehicle Dynamics Control
system except when absolutely neces-
sary. .
Even when the Vehicle Dynamics
Control system is deactivated, compo-
nents of the brake control system may
still activate. When the brake control
system is activated, the Vehicle Dy-
namics Control operation indicator
light illuminates.
Starting and operating
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7

Black plate (297,1)
北米Model "A1130BE-A" EDITED: 2011/ 6/ 7
lead to loss of vehicle control.
. You must install four tires that are
of the same size, circumferences,
construction, manufacturer,
brand (tread pattern), degree of
wear, speed symbol and load
index. Mixing tires of other sizes,
circumferences or constructions
may result in severe mechanical
damage to the drive train of your
vehicle and may affect ride,
handling, braking and speed-
ometer/odometer calibration. It
also may be dangerous and lead
to loss of vehicle control.
CAUTION
If you use a temporary spare tire to
replace a flat tire, be sure to use the
original temporary spare tire stored
in the vehicle. Using other sizes may
result in severe mechanical damage
to the drive train of your vehicle.
All-Wheel Drive distributes the engine
power to all four wheels. AWD models
provide better traction when driving on
slippery, wet or snow-covered roads and
when moving out of mud, dirt and sand.
By shifting power between the front and
rear wheels, SUBARU AWD can also
provide added traction during acceleration
and added engine braking force during
deceleration.
Therefore, your SUBARU AWD vehicle
may handle differently than an ordinary
two wheel drive vehicle and it contains
some features unique to AWD. For safety
purposes as well as to avoid damaging
the AWD system, you should keep the
following tips in mind.
. An AWD model is better able to climb
steeper roads under snowy or slippery conditions than a two wheel drive vehicle.
There is little difference in handling,
however, during extremely sharp turns or
sudden braking. Therefore, when driving
down a slope or turning corners, be sure
to reduce your speed and maintain an
ample distance from other vehicles.
.
Always check the cold tire pressure
before starting to drive. The recom-
mended tire pressure is provided on the
tire placard, which is located under the
door latch on the driver ’s side.
. Frequent driving of an AWD vehicle in
hard driving conditions such as steep hills
or dusty roads will necessitate more
frequent replacement of engine oil, brake
fluid and transmission oil than that speci-
fied in the “Warranty and Maintenance
Booklet ”.
. There are some precautions that you
must observe when towing your vehicle.
For detailed information, refer to “Towing”
F 9-12.
Driving tips
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