service SUBARU WRX 2018 Repair Manual

(525,1)
北米Model "A1700BE-B" EDITED: 2017/ 10/ 11
Brake pedalCheck the brake pedal free play and
reserve distance according to the main-
tenance schedule in the“Warranty and
Maintenance Booklet”.&Checking the brake pedal free
play1) 0.02–0.11 in (0.5–2.7 mm)Stop the engine and firmly depress the
brake pedal several times. Lightly pull the
brake pedal up with one finger to check the
free play with a force of less than 2 lbf (10
N, 1 kgf).
If the free play is not within proper
specification, contact your SUBARU deal-
er.
&Checking the brake pedal re-
serve distance1) More than 2.56 in (65 mm)Depress the pedal with a force of approxi-
mately 66 lbf (294 N, 30 kgf) and measure
the distance between the upper surface of
the pedal pad and the floor.
When the measurement is smaller than
the specification, or when the pedal does
not operate smoothly, contact with your
SUBARU dealer.
Clutch pedal (MT models)Check the clutch pedal free play according
to the maintenance schedule in the“War-
ranty and Maintenance Booklet”.&Checking the clutch functionCheck the clutch engagement and disen-
gagement.
1. With the engine idling, check that there
are no abnormal noises when the clutch
pedal is depressed, and that shifting into
1st or reverse feels smooth.
2. Start the vehicle by releasing the pedal
slowly to check that the engine and
transmission smoothly couple without
any sign of slippage.
–CONTINUED–
Maintenance and service/Brake pedal
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(526,1)
北米Model "A1700BE-B" EDITED: 2017/ 10/ 11
&Checking the clutch pedal
free play1) 0.16–0.43 in (4.0–11.0 mm)Lightly depress the clutch pedal down with
your finger until you feel resistance, and
check the free play.
If the free play is not within proper
specification, contact your SUBARU deal-
er.
Hill start assist systemEnsure that the Hill start assist system
operates properly under the following
circumstances.
1. Stop the vehicle on an uphill grade by
depressing the brake pedal (all models)
and clutch pedal (MT models only), with
the engine running.
2. Make sure that the vehicle does not
move backward for several seconds after
the brake pedal is released.
3. Then make sure the vehicle starts
climbing the grade by following the normal
starting procedures.
If the Hill start assist system does not
operate as described above, contact your
SUBARU dealer.
Replacement of brake pad
and liningThe disc brakes have audible wear in-
dicators on the brake pads. If the brake
pads wear close to their service limit, the
wear indicator makes a very audible
scraping noise when the brake pedal is
applied.
If you hear this scraping noise each time
you apply the brake pedal, have the brake
pads serviced by your SUBARU dealer as
soon as possible.
Maintenance and service/Hill start assist system
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(527,1)
北米Model "A1700BE-B" EDITED: 2017/ 10/ 11
CAUTION
.It is recommended that you dis-
connect the vehicle battery be-
fore replacing the brake pad.
However, it is dangerous to dis-
connect the vehicle battery. We
recommend that you have your
SUBARU dealer replace the brake
pad.
.If you continue to drive despite
the scraping noise from the audi-
ble brake pad wear indicator, it
will result in the need for costly
brake rotor repair or replace-
ment.&Breaking-in of new brake
pads (models with electronic
parking brake system)When replacing the brake pad, use only
genuine SUBARU parts. After replace-
ment, break in the new parts as follows.
!Brake pad
While maintaining a speed of 30 to 40 mph
(50 to 65 km/h), step on the brake pedal
lightly. Repeat this five or more times. Also,
apply and release the electronic parking
brake five or more times.
&Breaking-in of new brake
pads and linings (models
without electronic parking
brake system)When replacing the brake pad or lining,
use only genuine SUBARU parts. After
replacement, break in the new parts as
follows.
!Brake pad and lining
While maintaining a speed of 30 to 40 mph
(50 to 65 km/h), step on the brake pedal
lightly. Repeat this five or more times.
!Parking brake lining
1. Drive the vehicle at a speed of approxi-
mately 22 mph (35 km/h).
2. With the parking brake release button
pushed in, pull the parking brake lever
SLOWLY and GENTLY (pulling with a
force of approximately 33.7 lbf [150 N,
15.3 kgf]).
3. Drive the vehicle for approximately 220
yards (200 meters) in this condition.
4. Wait 5 to 10 minutes for the parking
brake to cool down. Repeat this proce-
dure.
5. Check the parking brake stroke. If the
parking brake stroke is out of the specified
range, adjust it by turning the adjusting nut
located on the parking brake lever.
Parking brake stroke:
7–8 notches / 45 lbf (200 N, 20.4 kgf)
WARNING
Select a safe location and situation
for break-in driving.
CAUTION
Pulling the parking brake lever too
forcefully may cause the rear wheels
to lock. To avoid this, be certain to
pull the lever up slowly and gently.
Maintenance and service/Replacement of brake pad and lining
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(528,1)
北米Model "A1700BE-B" EDITED: 2017/ 10/ 11
Parking brake stroke (models
without electronic parking
brake system)Check the parking brake stroke according
to the maintenance schedule in the“War-
ranty and Maintenance Booklet”.
When the parking brake is properly ad-
justed, braking power is fully applied by
pulling the lever up 7 to 8 notches gently
but firmly (approximately 45 lbf [200 N,
20.4 kgf]). If the parking brake lever stroke
is not within the specified range, have the
brake system checked and adjusted at
your SUBARU dealer.
Tires and wheels&Types of tiresYou should be familiar with type of tires
present on your vehicle.
!All season tires
All season tires are designed to provide an
adequate measure of traction, handling
and braking performance in year-round
driving including snowy and icy road
conditions. However all season tires do
not offer as much traction performance as
winter (snow) tires in heavy or loose snow
or on icy roads.
All season tires are identified by“ALL
SEASON”and/or“M+S”(Mud & Snow) on
the tire sidewall.
!Summer tires
Summer tires are high-speed capability
tires best suited for highway driving under
dry conditions.
Summer tires are inadequate for driving on
slippery roads such as on snow-covered or
icy roads.
If you drive your vehicle on snow-covered
or icy roads, we strongly recommend the
use of winter (snow) tires.
When installing winter tires, be sure to
replace all four tires.!Winter (snow) tires
Winter tires are best suited for driving on
snow-covered and icy roads. However
winter tires do not perform as well as
summer tires and all season tires on roads
other than snow-covered and icy roads.
&Tire pressure monitoring
system (TPMS) (if equipped)The 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 monitor-
ing system will activate only when the
vehicle is driven. 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).
Maintenance and service/Parking brake stroke (models without electronic parking brake system)
11-30

(529,1)
北米Model "A1700BE-B" EDITED: 2017/ 10/ 11
Low tire pressure warning lightIf you adjust the tire pressures in a warm
garage and will then drive the vehicle in
cold outside air, the resulting drop in tire
pressures may cause the low tire pressure
warning light to illuminate. To avoid this
problem when adjusting the tire pressures
in a warm garage, inflate the tires to
pressures higher than those shown on
the tire placard. Specifically, inflate them
by an extra 1 psi (6.9 kPa, 0.07 kgf/cm
2) for
every difference of 108F (5.68C) between
the temperature in the garage and the
temperature outside. By way of example,
the following table shows the required tire
pressures that correspond to various out-
side temperatures when the temperature
in the garage is 608F (15.68C).Example:
Tire size: 245/40R18 97W
Standard tire pressures:
Front: 33 psi (230 kPa, 2.3 kgf/cm
2)
Rear: 32 psi (220 kPa, 2.2 kgf/cm2)
Garage temperature: 608F (15.68C)
Outside
temperatureAdjusted pressure
[psi (kPa, kgf/cm
2)]
Front Rear
308F(18C) 36 (250, 2.5) 35 (240, 2.4)
108F(128C) 38 (260, 2.6) 37 (255, 2.55)
108F(238C) 40 (275, 2.75)39 (270, 2.7)
If the low tire pressure warning light
illuminates when you drive the vehicle in
cold outside air after adjusting the tire
pressures in a warm garage, re-adjust the
tire pressures using the method described
above. Then, increase the vehicle speed
to at least 20 mph (32 km/h) and check to
see that the low tire pressure warning light
turns off a few minutes later. If the low tire
pressure warning light does not turn off,
the tire pressure monitoring system may
not be functioning normally. In this event,
go to a SUBARU dealer to have the
system inspected as soon as possible.
While the vehicle is driven, friction be-
tween tires and the road surface causes
the tires to warm up. After illumination ofthe low tire pressure warning light, any
increase in the tire pressures caused by an
increase in the outside air temperature or
by an increase in the temperature in the
tires can cause the low tire pressure
warning light to turn off.
System resetting is necessary when the
wheels are changed (for example, a switch
to snow tires) and new TPMS valves are
installed on the newly fitted wheels. Have
this work performed by a SUBARU dealer
following wheel replacement.
It may not be possible to install TPMS
valves on certain wheels that are on the
market. Therefore, if you change the
wheels (for example, a switch to snow
tires), use wheels that have the same part
number as the standard-equipment
wheels. Without four operational TPMS
valve/sensors on the wheels, the TPMS
will not fully function and the warning light
on the combination meter will illuminate
steadily after blinking for approximately
one minute.
When a tire is replaced, adjustments are
necessary to ensure continued normal
operation of the tire pressure monitoring
system. As with wheel replacement, there-
fore, you should have the work performed
by a SUBARU dealer.
–CONTINUED–
Maintenance and service/Tires and wheels
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(530,1)
北米Model "A1700BE-B" EDITED: 2017/ 10/ 11
WARNING
If the low tire pressure warning light
does not illuminate briefly after the
ignition switch is turned ON or the
light illuminates steadily after blink-
ing for approximately one minute,
you should have your Tire Pressure
Monitoring System checked at a
SUBARU dealer as soon as possi-
ble.
If this light illuminates while driving,
never brake suddenly. Instead, per-
form the following procedure. Other-
wise an accident involving serious
vehicle damage and serious perso-
nal injury could occur.
1) Keep driving straight ahead while
gradually reducing speed.
2) Slowly pull off the road to a safe
place.
If this light still illuminates while
driving after adjusting the tire pres-
sure, a tire may have significant
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/transmitter
being transferred, the low tire pres-sure warning light will illuminate
steadily after blinking for approxi-
mately 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 system resetting. If the light
illuminates steadily after blinking
for approximately one minute,
promptly contact a SUBARU dealer
to have the system inspected.
&Tire inspectionCheck on a daily basis that the tires are
free from serious damage, nails, and
stones. At the same time, check the tires
for abnormal wear.
Contact your SUBARU dealer immediately
if you find any problem.NOTE.When the wheels and tires strike
curbs or are subjected to harsh treat-
ment as when the vehicle is driven on a
rough surface, they can suffer damage
that cannot be seen with the naked eye.
This type of damage does not become
evident until time has passed. Try not to
drive over curbs, potholes or on other
rough surfaces. If doing so is unavoid-able, keep the vehicle’s speed down to
a walking pace or less, and approach
the curbs as squarely as possible. Also,
make sure the tires are not pressed
against the curb when you park the
vehicle.
.If you feel unusual vibration while
driving or find it difficult to steer the
vehicle in a straight line, one of the tires
and/or wheels may be damaged. Drive
slowly to the nearest authorized
SUBARU dealer and have the vehicle
inspected.
&Tire pressures and wearMaintaining the correct tire pressures
helps to maximize the tires’service lives
and is essential for good running perfor-
mance. Check and, if necessary, adjust
the pressure of each tire (including the
spare) at least once a month (for example,
during a fuel stop) and before any long
journey.
Maintenance and service/Tires and wheels
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(531,1)
北米Model "A1700BE-B" EDITED: 2017/ 10/ 11
Tire placardCheck the tire pressures when the tires are
cold. Use a pressure gauge to adjust the
tire pressures to the values shown on the
tire placard. The tire placard is located on
the door pillar on the driver’s side.
Driving even a short distance warms up
the tires and increases the tire pressures.
Also, the tire pressures are affected by the
outside temperature. It is best to check tire
pressure outdoors before driving the ve-
hicle.
When a tire becomes warm, the air inside it
expands, causing the tire pressure to
increase. Be careful not to mistakenly
release air from a warm tire to reduce its
pressure.
NOTE.The air pressure in a tire increases
by approximately 4.3 psi (30 kPa, 0.3
kgf/cm
2) when the tire becomes warm.
.The tires are considered cold when
you have parked the vehicle for at least
three hours or have driven less than
one mile (1.6 km).
WARNING
Do not let air out of warm tires to
adjust pressure. Doing so will result
in low tire pressure.
Incorrect tire pressures detract from con-
trollability and ride comfort, and they cause
the tires to wear abnormally..Correct tire pressure(tread worn
evenly)
Roadholding is good, and steering is
responsive. Rolling resistance is low, so
fuel consumption is also lower.
–CONTINUED–
Maintenance and service/Tires and wheels
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(532,1)
北米Model "A1700BE-B" EDITED: 2017/ 10/ 11
.Under inflated tire(tread worn on
shoulders)Rolling resistance is high, so fuel con-
sumption is also higher..Over inflated tire(tread worn in the
center)
Ride comfort is poor. Also, the tire magni-
fies the effects of road-surface bumps and
dips, possibly resulting in vehicle damage.
If the tire placard shows tire pressures for
the vehicle when fully loaded, adjust the
tire pressures to the values that match the
loading conditions.
WARNING
Driving at high speeds with exces-
sively low tire pressures can cause
the tires to deform severely and to
rapidly heat up. A sharp increase in
temperature could cause tread se-
paration, and destruction of the
tires. The resulting loss of vehiclecontrol could lead to an accident.
&Wheel balanceEach wheel was correctly balanced when
your vehicle was new, but the wheels will
become unbalanced as the tires become
worn during use. Wheel imbalance causes
the steering wheel to vibrate slightly at
certain vehicle speeds and detracts from
the vehicle’s straight-line stability. It can
also cause steering and suspension sys-
tem problems and abnormal tire wear. If
you suspect that the wheels are not
correctly balanced, have them checked
and adjusted by your SUBARU dealer.
Also have them adjusted after tire repairs
and after tire rotation.
CAUTION
Loss of correct wheel alignment
causes the tires to wear on one side
and reduces the vehicle’s running
stability. Contact your SUBARU
dealer if you notice abnormal tire
wear.
Maintenance and service/Tires and wheels
11-34

(533,1)
北米Model "A1700BE-B" EDITED: 2017/ 10/ 11
NOTEThe suspension system is designed to
hold each wheel at a certain alignment
(relative to the other wheels and to the
road) for optimum straight-line stability
and cornering performance.&Wear indicators1) New tread
2) Worn tread
3) Tread wear indicatorEach tire incorporates a tread wear in-
dicator, which becomes visible when the
depth of the tread grooves decreases to
0.063 in (1.6 mm). Replace the tire when
the tread wear indicator appears as a solid
band across the tread.
WARNING
When a tire’s tread wear indicator
becomes visible, the tire is worn
beyond the acceptable limit and you
must replace it immediately. With a
tire in this condition, driving at high
speeds in wet weather can cause the
vehicle to hydroplane. The resulting
loss of vehicle control can lead to an
accident.NOTEFor safety, inspect tire tread regularly
and replace the tires before their tread
wear indicators become visible.
&Rotational direction of tiresExample of rotational direction marked on
the sidewall
1) FrontIf the tires have specific rotational direc-
tion, refer to the arrow marked on the side
wall.
The arrow should be pointing forward
when the wheels are fitted.
–CONTINUED–
Maintenance and service/Tires and wheels
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(534,1)
北米Model "A1700BE-B" EDITED: 2017/ 10/ 11
&Tire rotationVehicles equipped with 4 non-unidirec-
tional tires
1) Front
Vehicles equipped with unidirectional
tires
1) FrontTire wear varies from wheel to wheel.
Move the tires to the positions shown in the
illustration each time they are rotated. For
the tire rotation schedule, refer to the
“Warranty and Maintenance Booklet”.
Replace any damaged or unevenly worn
tires at the time of rotation. After tire
rotation, adjust the tires pressures and
make sure the wheel nuts are correctly
tightened.
After driving approximately 600 miles
(1,000 km), check the wheel nuts again
and retighten any nut that has become
loose.
&Tire replacementThe wheels and tires are important and
integral parts of your vehicle’s design; they
cannot be changed arbitrarily. The tires
fitted as standard equipment are optimally
matched to the characteristics of the
vehicle and were selected to give the best
possible combination of running perfor-
mance, ride comfort, and service life. It is
essential for every tire to have a size and
construction matching those shown on the
tire placard and to have a speed symbol
and load index matching those shown on
the tire placard.
Using tires of a non-specified size detracts
from controllability, ride comfort, braking
performance, speedometer accuracy and
odometer accuracy. It also creates incor-
rect body-to-tire clearances and inappro-
priately changes the vehicle’s ground
clearance.
All four tires must be the same in terms of
manufacturer, brand (tread pattern), con-
struction, and size. You are advised to
replace the tires with new ones that are
identical to those fitted as standard equip-
ment.
For safe vehicle operation, SUBARU
recommends replacing all four tires at the
same time.
Maintenance and service/Tires and wheels
11-36