2012 SUBARU IMPREZA WRX stop start

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 andreconnected.. 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 release
When 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
7-21

7-24Starting and operating
Limited slip differential (LSD) (STI)
The LSD provides optimum distribution of
power according to the difference in
revolutions between the right and left
wheels that may be caused by certain
driving conditions, thereby improving driv-
ing stability on snow-covered, muddy or
other slippery roads or when high speeddriving.
CAUTION
. Never start the engine while a tire
on one side is jacked up, as the
vehicle may move.
. If one tire is spinning in mud,
avoid continued spinning at high
speed as this could adversely
affect the LSD.
. 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 will adversely affect
the LSD. Power steering
The power steering system operates only
when the engine is running.
If you lose power steering assist because
the engine stops or the system fails to
function, you can steer but it will take
much more effort.
CAUTION
Do not hold the steering wheel at the
fully locked position left or right for
more than 5 seconds. This may
damage the power steering pump.
NOTE
Right after the engine has been started
and before it has warmed up, you may
hear a noise coming from areas adja-
cent to the power steering pump which
is located at the right-front area of the
engine compartment. This noise is
normal. It does not indicate power
steering system trouble. Braking &
Braking tips
WARNING
Never rest your foot on the brake
pedal while driving. This can cause
dangerous overheating of the
brakes and needless wear on the
brake pads and linings.
! When the brakes get wet
When driving in rain or after washing the
vehicle, the brakes may get wet. As a
result, brake stopping distance will be
longer. To dry the brakes, drive the vehicle
at a safe speed while lightly depressing
the brake pedal to heat up the brakes. ! Use of engine braking
Remember to make use of engine braking
in addition to foot braking. When descend-
ing a grade, if only the foot brake is used,
the brakes may start working improperly
because of brake fluid overheating,
caused by overheated brake pads. To
help prevent this, shift into a lower gear to
get stronger engine braking. ! Braking when a tire is punctured
Do not depress the brake pedal suddenly
when a tire is punctured. This could cause

a loss of control of the vehicle. Keep
driving straight ahead while gradually
reducing speed. Then slowly pull off the
road to a safe place. &Brake system
! Two separate circuits
Your vehicle has two separate circuit
brake systems. Each circuit works diag-
onally across the vehicle. If one circuit of
the brake system should fail, the other half
of the system still works. If one circuit fails,
the brake pedal will go down much closer
to the floor than usual and you will need to
press it down much harder. And a much
longer distance will be needed to stop thevehicle. ! Brake booster
The brake booster uses engine manifold
vacuum to assist braking force. Do not
turn off the engine while driving because
that will turn off the brake booster, result-
ing in poor braking power.
The brakes will continue to work even
when the brake booster completely stops
functioning. If this happens, however, you
will have to depress the pedal much
harder than normal and the braking dis-
tance will increase. !
Brake assist system
WARNING
Do not be overconfident about the
brake assist. It is not a system that
brings more braking ability to the
vehicle beyond its braking capabil-
ity. Always use the utmost care
when driving regarding vehicle
speed and safe distance.
CAUTION
When you need to brake suddenly,
continue depressing the brake pedal
strongly to bring the effect of the
brake assist.
Brake assist is a driver assistance system.
It assists the brake power when the driver
cannot depress the brake pedal strongly
and the brake power is insufficient.
Brake assist generates the brake power
according to the speed at which the driver
depresses the brake pedal. NOTE
When you depress the brake pedal
strongly or suddenly, the following
phenomena occur. However, even
though these occur, they do not indi- cate any malfunctions, and the brake
assist system is operating properly. .
You might feel that the brake pedal
is applied by lighter force and gener-
ates a greater braking force.. You might hear the sound of ABS
operating from the engine compart-ment. & Disc brake pad wear warning indicators
The disc brake pad wear warning indica-
tors on the disc brakes give a warning
noise when the brake pads are worn.
If a squeaking or scraping noise is heard
from the disc brakes while braking, im-
mediately have your vehicle checked by
your SUBARU dealer. Starting and operating
7-25

7-26Starting and operating
ABS (Anti-lock Brake Sys- tem)
The ABS system prevents the lock-up of
wheels which may occur during sudden
braking or braking on slippery road sur-
faces. This helps prevent the loss of
steering control and directional stability
caused by wheel lock-up.
When the ABS system is operating, you
may hear a chattering noise or feel a slight
vibration in the brake pedal. This is normal
when the ABS operates.
The ABS system will not operate when the
vehicle speed is below approximately 6
mph (10 km/h).
WARNING
Always use the utmost care in driving –overconfidence because
youaredrivingwithanABS
equipped vehicle could easily lead
to a serious accident.
CAUTION
. The ABS system does not always
decrease stopping distance. You
should always maintain a safe
following distance from other vehicles.
. When driving on badly surfaced
roads, gravel roads, icy roads, or
over deep newly fallen snow,
stopping distances may be long-
er for a vehicle with the ABS
system than one without. When
driving under these conditions,
therefore, reduce your speed and
leave ample distance from othervehicles.
. When you feel the ABS system
operating, you should maintain
constant brake pedal pressure.
Do not pump the brake pedal
since doing so may defeat the
operation of the ABS system.
& ABS system self-check
Just after the vehicle is started, you may
feel on the brake pedal a vibration similar
to when the ABS operates, and you may
also hear the sound of the ABS working
from the engine compartment. This is
caused by an automatic functional test of
the ABS system being carried out and
does not indicate any abnormal condition. & ABS warning light
Refer to “ABS warning light ”F 3-18. Electronic Brake Force Dis-
tribution (EBD) system
The EBD system maximizes the effective-
ness of the brakes by allowing the rear
brakes to supply a greater proportion of
the braking force. It functions by adjusting
the distribution of braking force to the rear
wheels in accordance with the vehicle
’s
loading condition and speed.
The EBD system is an integral part of the
ABS system and uses some of the ABSsystem ’s components to perform its func-
tion of optimizing the distribution of brak-
ing force. If any of the ABS components
used by the EBD system malfunction, the
EBD system also stops working.
When the EBD system is operating, you
may hear a chattering noise or feel a slight
vibration in the brake pedal. This is normal
and does not indicate a malfunction.

&Steps to take if EBD system malfunctions
If a malfunction occurs in the EBD system,
the system stops working and the brake
system warning light and ABS warning
light illuminate simultaneously.
The EBD system may be malfunctioning if
the brake system warning light and ABS
warning light illuminate simultaneously
during driving.
Even if the EBD system malfunctions, the
conventional braking system will still func-
tion. However, the rear wheels will be
more prone to locking when the brakes
are applied harder than usual and thevehicle ’s motion may therefore become
somewhat harder to control.
If the brake system warning light and ABS warning light illuminate simultaneously,
take the following steps.
1. Stop the vehicle in the nearest safe,
flat location.
2. Shut down the engine, apply the
parking brake, and then restart it.
3. Release the parking brake. If both
warning lights turn off, the EBD system
may be malfunctioning. Drive carefully to
the nearest SUBARU dealer and have the
system inspected.
4. If both warning lights illuminate again
and remain illuminated after the engine
has been restarted, shut down the engine
again, apply the parking brake, and check
the brake fluid level. Refer to
“Brake fluid ”
F 11-18.
5. If the brake fluid level is not below the“ MIN ”mark, the EBD system may be
malfunctioning. Drive carefully to the
nearest SUBARU dealer and have the
system inspected.
6. If the brake fluid level is below the “ MIN ”mark, DO NOT drive the vehicle.
Instead, have the vehicle towed to the
nearest SUBARU dealer for repair.
WARNING
. Driving with the brake system
warning light illuminated is dan- gerous. This indicates your brake
system may not be working
properly. If the light remains
illuminated, have the brakes in-
spected by a SUBARU dealer
immediately.
. If at all in doubt about whether
the brakes are operating prop-
erly, do not drive the vehicle.
Have your vehicle towed to the
nearest SUBARU dealer for re-
pair. Starting and operating
7-27

7-34Starting and operating
When parking on a hill, always turn the
steering wheel. When the vehicle is
headed up the hill, the front wheels should
be turned away from the curb.
When facing downhill, the front wheels
should be turned into the curb.
WARNING
. Never leave unattended children
or pets in the vehicle. They could
accidentally injure themselves or
others through inadvertent op-
eration of the vehicle. Also, on
hot or sunny days, the tempera-
ture in a closed vehicle could
quickly become high enough to
cause severe or possibly fatal
injuries to people.
. Do not park the vehicle over
flammable materials such as dry
grass, waste paper or rags, as
they may burn easily if they come
near hot engine or exhaust sys-
tem parts.
. Be sure to stop the engine if you
take a nap in the vehicle. If
engine exhaust gas enters the
passenger compartment, occu-
pants in the vehicle could die
from carbon monoxide (CO) con-
tained in the exhaust gas.
CAUTION
If your vehicle has a front under-
spoiler and rear underspoiler (both
optional), pay attention to blocks and other obstructions on the
ground when parking. The under-
spoilers could be damaged by con-
tact with them.

Hill start assist system
CAUTION
The Hill start assist system is a
device only for helping the driver
to START the vehicle on an uphill
grade. To prevent accidents when
the vehicle is parked on a slope, be
sure to firmly set the parking brake.
When setting the parking brake,
make sure that the vehicle remains
stationary when the clutch pedal isreleased.
The Hill start assist system is a device to
make starting on an uphill grade easier.
On an uphill grade, when the clutch pedal is depressed while the brake pedal is also
depressed, braking power is maintained
temporarily by the Hill start assist system
when the brake pedal is released. The
driver is therefore able to start the vehicle
the same way as on a level grade, just
using the clutch and accelerator pedal.
The Hill start assist system does not
operate when the vehicle is facing down-
hill. And the Hill start assist system may
not operate on slight grades.
When starting in reverse and using the Hill
start assist system, a braking effect may
be felt even after the brake pedal has
been released. However, this braking
effect should disappear once the clutch
pedal is released.
A slight jolt may be felt when the vehiclebegins to move forward after being re- versed.
If the braking power of the Hill start assist
system is insufficient after the brake pedal
is released, apply more braking power by
depressing the brake pedal again. &
To activate/deactivate the Hill
start assist system (STI)
CAUTION
While the Hill start assist system is
deactivated, when starting on an
uphill grade, braking power is not
maintained if the brake pedal is
released. Start on an uphill grade
by using the parking brake.
You can activate/deactivate the Hill start
assist system according to the followingprocedure. ! To deactivate
1. Stop your vehicle in a flat and safe
place and apply the parking brake.
2. Turn off the engine.
3. Restart the engine. Starting and operating
7-35
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To resume the cruise control after it has
been temporarily canceled and with vehi-
cle speed of approximately 20 mph (32
km/h) or more, push the“RES/ACC ”
button to return to the original cruising
speed automatically.
The cruise control set indicator light on the
combination meter will automatically illu-
minate at this time. & To turn off the cruise control
There are two ways to turn off the cruise control: . Push the “CRUISE ”main switch button
again.. Turn the ignition switch to the “Acc ”or
“ LOCK ”position (but only when the
vehicle is completely stopped). &
To change the cruising speed
! To increase the speed (by button)
Push the “RES/ACC ”button and hold it
until the vehicle reaches the desired
speed. Then, release the button. The
vehicle speed at that moment will be
memorized and treated as the new setspeed.
When the difference between the actual
vehicle speed and the set speed is less
than 4 mph (6.8 km/h), the set speed can
be increased 1 mph (1.6 km/h) each time
by pressing the “RES/ACC ”button quickly. !
To increase the speed (by accel-
erator pedal)
1. Depress the accelerator pedal to
accelerate the vehicle to the desiredspeed.
2. Push the “SET/COAST ”button once.
Now the desired speed is set and the
vehicle will keep running at that speed
without depressing the accelerator pedal.
NOTE
If the difference between the actual
vehicle speed when the button is
pushed and the speed last time you
set is less than 4 mph (6.8 km/h), the
vehicle speed will be lowered by 1 mph
(1.6 km/h). This occurs because the
cruise control system unit regards this
operation as that intended to decrease
the vehicle speed. Starting and operating
7-39
– CONTINUED –