brake SUBARU WRX 2018 Service Manual

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北米Model "A1700BE-B" EDITED: 2017/ 10/ 11
!Except STI
When you select the Sport Sharp (S#)
mode with the select lever in the“D”
position, the transmission gear ratio will
shift from variable speed to eight-speed.
The select lever/gear position indicator
display will change from“D”to the gear
position.
When selecting Sport Sharp (S#) mode,
the following controls will be applied.
.Uphill control
Prevents unnecessary shift-up/shift-down
during ascent.
.Cornering control
While turning, if there is a large centrifugal
force, shift-up will not occur: during re-
acceleration.
.Braking control
At the beginning of corners etc., heavy
application of the brake pedal will cause
automatic downshift and gently re-accel-
erate.
.Sudden acceleration return control
During acceleration, if acceleration pedal
is returned suddenly (for example, at
corners etc.), shift-up will not be applied.
&SI-DRIVE switch
NOTE.The next time you turn on the engine,
the following SI-DRIVE mode will be
selected.
–Intelligent (I) mode if you have
turned off the engine in the Intelli-
gent (I) mode
–Sport (S) mode if you have turned
off the engine in the Sport (S) mode
or Sport Sharp (S#) mode
.If the CHECK ENGINE warning light/
malfunction indicator light illuminates
during engine operation, the SI-DRIVE
mode changes to the Sport (S) mode. In
this case, it is not possible to change to
the Sport Sharp (S#) mode or Intelligent
(I) mode.
.If the engine coolant temperature
becomes so high that the engine could
overheat, it is not possible to change to
the Sport Sharp (S#) mode. While the
vehicle is in the Sport Sharp (S#) mode,
it changes to the Sport (S) mode when
the engine coolant temperature in-
creases.
.If any of the SI-DRIVE indicators
blink, the SI-DRIVE system may be
malfunctioning. Contact your SUBARU
dealer.!STI
SI-DRIVE switchTo select the Intelligent (I) mode:
Push the SI-DRIVE switch.
To select the Sport (S) mode:
Rotate the SI-DRIVE switch to the left.
To select the Sport Sharp (S#) mode:
Rotate the SI-DRIVE switch to the right.
After operating the SI-DRIVE switch, the
switch returns to its original position.
Starting and operating/SI-DRIVE
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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 causea 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 diagonally
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 the
vehicle.
!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, resulting 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 distance 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 obtain 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.NOTEWhen you depress the brake pedal
strongly or suddenly, the following
phenomena occur. However, even
though these occur, they do not indi-
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Starting and operating/Braking
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cate any malfunctions, and the brake
assist system is operating properly.
.You might feel that the brake pedal is
applied by lighter force and generates a
greater braking force.
.You might hear an ABS operating
noise from the engine compartment.&Disc brake pad wear warning
indicatorsThe 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.
&High performance brake sys-
tem (STI)Your vehicle is equipped with large, high
performance brake pads that provide
optimum braking force under various driv-
ing conditions. The brake pads have the
following characteristics.
Brake noises
The brake pads are made of iron-based
material. Therefore, unusual noise may be
heard when depressing the brake pedal
slightly before stopping completely. How-
ever, this does not indicate a malfunction.
Discoloration
Frequent severe driving, such as repeated
driving on sharp uphill or downhill grades,
can cause discoloration of the paint on the
brake calipers. The discoloration will not
affect the braking performance.
Stuck brake pads
.If the vehicle is left parked for an
extended period of time with the brake
system wet, the iron in the brake pads may
form rust and cause the brake pads and
disc rotors to stick together. This may
result in noise or vibration while driving. If
this occurs, fully depress the brake pedal
several times to free the brake pads.
.If the vehicle is left parked for an
extended period of time in a cold tempera-ture, the brake pads and disc rotors may
be frozen and stuck together. In this case,
it may be difficult to start the vehicle.
Brake dust
Due to the material used for the brake
pads, the wheels may become covered in
brake dust. This is not a malfunction, and
will not affect the brake performance.
&Red caliper with sports brake
pad (if equipped)Brake noises
The brake pads are made of iron-based
material. Therefore, unusual noise may be
heard when depressing the brake pedal
slightly before stopping completely. How-
ever, this does not indicate a malfunction.
Brake dust
Due to the material used for the brake
pads, the wheels may become covered in
brake dust. This is not a malfunction, and
will not affect the brake performance.
Starting and operating/Braking
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ABS (Anti-lock Brake Sys-
tem)The ABS prevents the lock-up of wheels
which may occur during sudden braking or
braking on slippery road surfaces. This
helps prevent the loss of steering control
and directional stability caused by wheel
lock-up.
When the ABS 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 will not operate when the vehicle
speed is below approximately 6 mph (10
km/h).
WARNING
Always use the utmost care in driv-
ing–overconfidence because you
are driving a vehicle with the ABS
could easily lead to a serious acci-
dent.
CAUTION
.The ABS does not always de-
crease 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 than
one without. When driving under
these conditions, therefore, re-
duce your speed and leave ample
distance from other vehicles.
.When you feel the ABS operating,
you should maintain constant
brake pedal pressure. Do not
pump the brake pedal since
doing so may defeat the opera-
tion of the ABS system.
&ABS self-checkJust 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 being carried out and does not
indicate any abnormal condition.&ABS warning lightRefer to“ABS warning light”F3-20.
Starting and operating/ABS (Anti-lock Brake System)
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Electronic Brake Force Dis-
tribution (EBD) systemThe 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 and uses some of the ABS compo-
nents to perform its function of optimizing
the distribution of braking 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
malfunctionsBrake and ABS warning lightIf 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
while 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 the vehicle’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. Apply the parking brake and turn off the
engine.
3. Restart the engine.
4. Release the parking brake.
Even if both warning lights turn off:
The EBD system may be malfunctioning.
Drive carefully to the nearest SUBARU
dealer and have the system inspected.
If both warning lights illuminate again
and remain illuminated after restarting
the engine:
1. Turn off the engine again.
2. Apply the parking brake.
3. Check the brake fluid level. For details
about checking the brake fluid level, refer
to“Checking the fluid level”F11-24.
.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.
.If the brake fluid level is below the“MIN”
mark, DO NOT drive the vehicle. Instead,
have the vehicle towed to the nearest
Starting and operating/Electronic Brake Force Distribution (EBD) system
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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 prop-
erly. If the light remains illumi-
nated, have the brakes inspected
by a SUBARU dealer immedi-
ately.
.If at all in doubt about whether the
brakes are operating properly, do
not drive the vehicle. Have your
vehicle towed to the nearest
SUBARU dealer for repair.
Vehicle Dynamics Control
system
WARNING
Always use the utmost care in driv-
ing–overconfidence because you
are driving a vehicle with the Vehicle
Dynamics Control system could ea-
sily lead to a serious 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 guaranteethat 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.
.Observe the following precau-
tions in order to ensure that the
Vehicle Dynamics Control sys-
tem is operating properly:
–Fit all four wheels with tires of
the same size, type, and
brand. Furthermore, 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 tempor-
ary spare tire to replace a flat
tire. With a temporary spare
tire, the effectiveness of the
Vehicle Dynamics Control
system is reduced and this
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Starting and operating/Vehicle Dynamics Control system
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should be taken into account
when driving the vehicle in
such a condition.
.If you use non-matching tires, the
Vehicle Dynamics Control sys-
tem may not operate correctly.
.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 neces-
sary. If you must turn off the
Vehicle Dynamics Control sys-
tem, drive very carefully accord-
ing to 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.
Activation of this function is shown byflashing the Vehicle Dynamics 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 shown by flashing
of the Vehicle Dynamics Control operation
indicator light.
Vehicle Dynamics Control operation indi-
cator lightNOTE.The Vehicle Dynamics Control sys-
tem may be considered normal when
the following conditions occur.
–Slight twitching of the brakepedal 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 circumstances shown in the
following list, 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 wheelto feel slightly
different compared to that for normal
conditions.
.It is always important to reduce
speed when approaching a corner,
even if your vehicle is equipped with
the Vehicle Dynamics Control system.
.Always turn off the engine before
replacing a tire. Failure to do so may
render the Vehicle Dynamics Control
Starting and operating/Vehicle Dynamics Control system
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off.
Creating an adequate driving wheel slip by
deactivating the Vehicle Dynamics Control
system temporarily may help to escape
from the following situations. Use the
Vehicle Dynamics Control OFF mode as
necessary.
.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
You should not deactivate the Vehicle
Dynamics Control system except under
the above-mentioned situations.NOTE.If you turn the ignition switch to the
“LOCK”/“OFF”position with the Vehi-
cle Dynamics Control system deacti-
vated, the system will be automatically
reactivated the next time the engine is
started.
.If you press and hold the switch for
30 seconds or longer, the Vehicle
Dynamics Control OFF 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”/“OFF”position and restart the
engine.
.When the Vehicle Dynamics Control
OFF mode is selected, the vehicle’s
running performance is comparable
with that of a vehicle that does not have
a Vehicle Dynamics Control system. 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.
Tire pressure monitoring
system (TPMS) (U.S.-spec.
models)Low tire pressure warning lightThe tire pressure monitoring system pro-
vides the driver with a warning message by
sending a signal from a sensor that is
installed in each wheel when tire pressure
is severely low.
The tire pressure monitoring system will
activate only when the vehicle is driven at
speeds above 20 mph (32 km/h). Also, this
system may not react immediately to a
sudden drop in tire pressure (for example,
a blow-out caused by running over a sharp
object).
Starting and operating/Tire pressure monitoring system (TPMS) (U.S.-spec. models)
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WARNING
.If the low tire pressure warning
light illuminates while driving,
never brake suddenly. Instead,
perform the following procedure.
Otherwise, an accident involving
serious vehicle damage and ser-
ious personal injury could occur.
(1) Keep driving straight ahead
while gradually reducing
speed.
(2) Slowly pull off the road to a
safe place.
(3) Check the pressure for all four
tires and adjust the pressure
to the COLD tire pressure
shown on the vehicle placard
on the door pillar on the
driver’s side.
Even when the vehicle is driven a
very short distance, the tires get
warm and their pressures in-
crease accordingly. Be sure to
let the tires cool thoroughly be-
fore adjusting their pressures to
the standard values shown on the
tire placard. Refer to“Tires and
wheels”F11-30. The tire pres-
sure monitoring system does not
function when the vehicle is sta-tionary. After adjusting the tire
pressures, increase the vehicle
speed to at least 20 mph (32 km/h)
to start the TPMS rechecking of
the tire inflation pressures. If the
tire pressures are now above the
severe low pressure threshold,
the low tire pressure warning
light should turn off a few min-
utes later.
If this light still illuminates while
driving after adjusting the tire
pressure, a tire may have signifi-
cant damage and a fast leak that
causes the tire to lose air rapidly.
If you have a flat tire, refer to“Flat
tires”F9-5.
.When a spare tire is mounted or a
wheel rim is replaced without the
original pressure sensor/trans-
mitter being transferred, the low
tire pressure warning light will
illuminate steadily after blinking
for approximately one minute.
This indicates the TPMS is unable
to monitor all four road wheels.
Contact your SUBARU dealer as
soon as possible for tire and
sensor replacement and/or sys-
tem resetting.
.When a tire is repaired with liquid
sealant, the tire pressure warningvalve and transmitter may not
operate properly. If a liquid sea-
lant is used, contact your nearest
SUBARU dealer or other qualified
service shop as soon as possi-
ble. Make sure to replace the tire
pressure warning valve and
transmitter when replacing the
tire. You may reuse the wheel if
there is no damage to it and if the
sealant residue is properly
cleaned off. Do not inject any tire
liquid or aerosol tire sealant into
the tires, as this may cause a
malfunction of the tire pressure
sensors. If the light illuminates
steadily after blinking for ap-
proximately one minute,
promptly contact a SUBARU
dealer to have the system in-
spected.
CAUTION
Do not place metal film or any metal
parts in the trunk. This may cause
poor reception of the signals from
the tire pressure sensors, and the
tire pressure monitoring system will
not function properly.
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Starting and operating/Tire pressure monitoring system (TPMS) (U.S.-spec. models)
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NOTEThis device complies with part 15 of the
FCC Rules. Operation is subject to the
following two conditions: (1) This de-
vice may not cause harmful interfer-
ence, and (2) this device must accept
any interference received, including
interference that may cause undesired
operation.
FCC CAUTION
Changes or modifications not ex-
pressly approved by the party respon-
sible for compliance could void the
user’s authority to operate the equip-
ment.
Parking your vehicle
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 them.
.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 passen-
ger compartment, occupants in
the vehicle could die from carbon
monoxide (CO) contained in the
exhaust gas.
CAUTION
TYPE RA: When parking the vehicle,
be careful not to contact a wheel
stop, etc. Doing so may damage the
bumpers, underside of the vehicle,
etc.&Parking brake (models with-
out electronic parking brake
system)To set the parking brake, depress the
brake pedal firmly and hold it down until
the parking brake lever is fully pulled up.To release the parking brake, perform the
following procedure.
1. Pull the lever up slightly.
Starting and operating/Parking your vehicle
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