SUBARU IMPREZA WRX 2007 3.G Owners Manual

7-14Starting and operating
!Center differential control dial and
indicator light
The control dial is located beside the
parking brake lever. By turning the control
dial forward and rearward, it is possible to
change the initial LSD torque.
The center differential indicator lights in
the combination meter give six levels of
indication. The indicator lights and control
dial are linked; when the dial is turned to
change the initial LSD torque, the illumi-
nation position of the indicator lights
changes accordingly.
Turn the dial forward to increase the initial
LSD torque; when the white line on the
dial reaches the frontmost position, the
initial LSD torque setting is maximum. The
center differential will then be almost
completely locked and the “LOCK ”indica-
tor light will come on.Turn the dial rearward to reduce the initial
LSD torque; when the white line reaches
the rearmost position, the initial LSD
torque will be minimum and the “
”
indicator light will come on. Under this
condition, only the Mechanical LSD torque
will limit the differential action.
CAUTION
. Do not turn the control dial when
a wheel slippage occurs. Wait
until the wheelspin has been
brought under control.
. Under any of the following con-
ditions, turn the center differen-
tial control dial to the rearmost
position 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. If you become stuck in
snow or mud, turning the center differ-
ential control dial to the frontmost
position will help move the vehicle
out. (The “LOCK ”indicator will come
on at the frontmost position.). During cornering or when making
turns (especially when getting 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 you turn the center
differential control dial to the rearmost position (minimum initial LSD torqueposition).
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 dial while quickly accelerating
or turning a tight corner, you may feel
slight shocks. This is due to differential
action by the center differential 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 in 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. Automatic transmission
The automatic transmission is electroni-
cally controlled and provides 4 forward
speeds and 1 reverse speed. NOTE .
When the engine coolant tempera-
ture is still low, your vehicle ’s auto-
matic transmission will up-shift at high-
er engine speeds than when the cool-
ant temperature is sufficiently high in
order to shorten the warm-up time and
improve driveability. The gearshift tim-
ing will automatically shift to the nor-
mal timing after the engine has warmedup. . Immediately after ATF (automatic
transmission fluid) is replaced, you
may feel that the automatic transmis-
sion operation is somewhat unusual.
This results from invalidation of data
the on-board computer has collected
and stored in memory to allow the
transmission to shift at the most appro-
priate times for the current condition of
your vehicle. Optimized shifting will be
restored as the vehicle continues to be
driven for a while. Starting and operating
7-15
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7-16Starting and operating
WARNING
Do not shift from the “P ” or “N ”
position into the “D ”, “3 ”, “2 ”, “1 ” or
“ R ” position while depressing the
accelerator pedal. This may cause
the vehicle to jump forward or back-ward.
CAUTION
. Shift into the “P ” or “R ” position
only after the vehicle is comple-
tely stopped. Shifting while the
vehicle is moving may cause
damage to the transmission.
. Do not race the engine for more
than 5 seconds in any position
except the “N ” or “P ” position
when the brake is set or when
chocks are used in the wheels.
This may cause the automatic
transmission fluid to overheat.
. Avoid shifting from one of the
forward driving positions into the“ R ” position or vice versa until
the vehicle has completely
stopped. Such shifting may
cause damage to the transmis-sion.
. When parking the vehicle, first securely apply the parking brake
and then place the selector lever
in the
“P ” position. Avoid parking
for a long time with the selector
lever in any other position as
doing so could result in a dead
battery.
& Selector lever
: With the brake pedal depressed, move
the lever along the gate.
: Move the lever along the gate.
The selector lever has seven positions. ! P (Park)
This position is for parking the vehicle and
starting the engine.
In this position, the transmission is me-
chanically locked to prevent the vehicle
from rolling freely.
When you park the vehicle, first set the
parking brake fully, then shift into the “P ”
position. Do not hold the vehicle with only
the transmission.
A shift interlock function is employed in the
automatic transmission system to ensure
safe starting of the vehicle.

To shift the selector lever from the“P ”
position to any other position, you have to
depress the brake pedal fully when the
ignition switch is in the “ON ”position. This
prevents the vehicle from lurching when it
is started.
If the shift lever does not move from the “ P ” position with the brake pedal de-
pressed, refer to the “Shift lock release ”
section in this chapter. ! R (Reverse)
This position is for backing the vehicle.
To shift from the “N ” to “R ” position, first
stop the vehicle completely then move the
lever to the “R ”position.
! N (Neutral)
This position is for restarting a stalledengine.
In this position the wheels and transmis-
sion are not locked. In this position, the
transmission is neutral; the vehicle will roll
freely, even on the slightest incline unless
the parking brake or foot brake is on.
Avoid coasting with the transmission neutral.
During coasting, there is no engine brak-
ing effect. NOTE
If you stop the engine with the selector
lever in the
“N ” position, move the
selector lever to the “P ” position
immediately. Otherwise, you may find
that the selector lever soon cannot be
moved to the “P ” position. If you find
that the selector lever cannot be moved
from the “N ” position to the “P ” posi-
tion, turn the ignition switch to the“ ON ”position and try again.
WARNING
Do not drive the vehicle with the
selector lever in the “N ” (neutral)
position. Engine braking has no
effect in this condition and the risk
of an accident is consequently in-creased.
! D (Drive)
This position is for normal driving.
The transmission automatically shifts into
a suitable gear from 1st to 4th according to
the vehicle speed and the acceleration
you require.
When more acceleration is required in this
position, press the accelerator pedal fully
to the floor and hold that position. The
transmission will automatically downshift to 3rd, 2nd or 1st gear. When you release
the pedal, the transmission will return to
the original gear position. !
While climbing a grade
When driving up hill, undesired upshift to
4th gear is prevented from taking place
when the accelerator pedal is released.
This minimizes the chances of subse-
quent downshifting to a lower gear when
accelerating again. This prevents re-
peated upshifting and downshifting result-
ing in a smoother operation of the vehicle. NOTE
The transmission may downshift to 2nd
or 1st gear, depending on the way the
accelerator pedal is pressed to accel-
erate the vehicle again. ! While going down a hill
When descending a steep hill, depressing
the brake pedal will cause the transmis-
sion to downshift to 3rd gear, thus apply-
ing engine braking. Reacceleration for a
short time will cause the transmission to
upshift normally. NOTE
In some cases, depressing the brake
pedal on a downhill grade does not
result in an automatic downshift to 3rd
gear. This can happen when the auto- Starting and operating
7-17
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7-18Starting and operating
matic transmission fluid temperature is
very low, for example, during driving
shortly after the vehicle has been
parked for an extended period of time.
When the ATF temperature has risen to
a certain level, automatic downshift
normally takes place. In the meantime,
downshift manually for engine braking
as required.
Also, downshifting when braking
downhill will not occur at speeds above
approximately 48 mph (78 km/h). !3 (Third)
This position is for using engine braking
when going down a hill or for climbing agrade.
The transmission automatically shifts into
a suitable gear from 1st to 3rd according
to the vehicle speed and the acceleration
you require.
When more acceleration is required in this
position, press the accelerator pedal fully
to the floor and hold that position. The
transmission will automatically downshift
to 2nd or 1st gear. When you release the
pedal, the transmission will return to the
original gear position. ! 2 (Second)
This position is for using engine braking
when going down a hill or for climbing a steep grade.
In this position, the transmission holds in
the 2nd gear.
Use this position when starting off from a
standstill on slippery road surfaces such
as mud or snow. It will ensure greatertraction. !
1 (First)
This position is for driving up or down very
steep grades, or driving through mud or
sand, or on slippery surfaces. In this
position, the transmission holds in the
1st gear. ! Maximum speeds
The following table shows the maximum
speeds that are possible with each differ-
ent gear.
When shifting down a gear, it is important
to confirm that the current vehicle speed is
not in excess of the Maximum Allowable
Speed of the gear which is about to beselected. mph (km/h)
Non-turbo models Turbo models
1 28 (45) 28 (45)
2 62 (100) 65 (104)
3 97 (156) 104 (167) NOTE
In order to prevent over-revving during
deceleration of the vehicle, the trans-
mission will remain in the current gear
if the speed of the vehicle is in excess
of the Maximum Allowable Speed for
the gear to which the selector lever has
been moved.
WARNING
When shifting down a gear, ensure
that the vehicle is not travelling at a
speed exceeding the Maximum Al-
lowable Speed for the gear which is
about to be selected. Failure to
observe this precaution can lead to
engine over-revving and this in turn
can result in engine damage.
In addition, sudden application of
engine brakes when the vehicle is
travelling on a slippery surface can
lead to wheel locking; as a conse-
quence, control of the vehicle may
be lost and the risk of an accidentincreased.
! Driving tips
. Always apply the foot or parking brake
when the vehicle is stopped in the “D ”, “3 ”,
“ 2 ”, “1 ” or “R ”position.

.Always set the parking brake when
parking your vehicle. Do not hold the
vehicle with only the transmission. . Do not keep the vehicle in a stationary
position on an uphill grade by using the “ D ”, “3 ”, “2 ”,or “1 ” position. Use the brake
instead.
The engine may, on rare occasions, knock
when the vehicle rapidly accelerates or
rapidly pulls away from a standstill. This
phenomenon is not an indication of a
problem in your vehicle.
& Shift lock release
If the selector lever does not move fromthe “P ” position with the brake pedal
depressed and the ignition switch in the“ ON ”position, perform the following steps:
To override the shift lock:
1. Set the parking brake and stop the engine.
2. Take out the screwdriver from the tool bag.
3. Remove the cover by prying on the
edge with the screwdriver.
4. Insert the screwdriver into the hole.
5. Push down on the screwdriver and
move the selector lever from the “P ”to the
“ N ”position.
6. Remove the screwdriver from the hole.
Depress the brake pedal and start the engine.
Take your vehicle to the nearest SUBARU
dealer immediately to have the systemrepaired.
Starting and operating
7-19

7-20Starting and operating
Limited slip differential (LSD)
(if equipped)
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. 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.
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. 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 push the pedal much harder than normal and the braking distance willincrease.
& 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. 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
you are driving with an ABS
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 Starting and operating
7-21
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7-22Starting and operating
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
The ABS warning light comes on when the
ignition switch is turned to the “ON ”
position and goes out after approximately
2 seconds.
This is an indication that the ABS system
is working properly.
When driving with an insufficient battery
voltage such as when the engine is jump
started, the ABS warning light may come
on. This is due to the low battery voltage
and does not indicate a malfunction.
When the battery becomes fully charged,
the light will go out.
CAUTION
If the warning light behaves as
follows, the ABS system may not
be working properly.
When the warning light is on, the
ABS function shuts down; however,
the conventional brake system con-
tinues to operate normally. . The warning light does not come
on when the ignition switch is
turned to the “ON ”position.
. The warning light comes on when
the ignition switch is turned tothe “ON ”position, but it does not
go out even when the vehicle
speed exceeds approximately 8
mph (12 km/h).
. The warning light comes on dur-
ing driving.
If these occur, have the ABS system
repaired at the first available oppor-
tunity by your SUBARU dealer.
NOTE
If the warning light behavior is as
described in the following, the ABS
system may be considered normal. . The warning light comes on right
after the engine is started but goes out

immediately, remaining off. .The warning light remains on after
the engine has been started, but it goes
out when the vehicle speed reaches
approximately 8 mph (12 km/h).. The warning light comes on during
driving, but it goes out immediately and
remains off. 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 function fail, 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 fails
If a malfunction occurs in the EBD system,
the system stops working and the brake
system warning light and ABS warning
light come on simultaneously.
The EBD system may be faulty if the
brake system warning light and ABS
warning light illuminate simultaneously
during driving.
Even if the EBD system fails, the conven-
tional braking system will still function.
However, the rear wheels will be more
prone to locking when the brakes are
applied harder than usual and the vehi-cle’s motion may therefore become some-
what harder to control.
If the brake system warning light and ABS Starting and operating
7-23
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