2019 LEXUS RC300 check

2536-3. Do-it-yourself maintenance
RC350AWD_RC350_RC300AWD_RC30
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Maintenance and care
■Brake fluid can absorb moisture from
the air
Excess moisture in the brake fluid can cause
a dangerous loss of braking efficiency. Use
only newly opened brake fluid.
Check the battery as follows.
■Battery exterior
Make sure that the battery terminals
are not corroded and that there are no
loose connections, cracks, or loose
clamps. Terminals
Hold-down clamp
■Before recharging
When recharging, the battery produces
hydrogen gas which is flammable and
explosive. Therefore, observe the following
before recharging:
●If recharging with the battery installed on
the vehicle, be sure to disconnect the
ground cable.
●Make sure the power switch on the char-
ger is off when connecting and discon-
necting the charger cables to the battery.
■After recharging/reconnecting the bat-
tery
The engine may not start. Follow the proce-
dure below to initialize the system.
1
Shift the shift lever to P.
2
Open and close either door.
3
Restart the engine.
●Unlocking the doors using the smart
access system with pu sh-button start may
not be possible immediately after recon-
necting the battery. If this happens, use
the wireless remote control or the
mechanical key to lock/unlock the doors.
●Start the engine with the engine switch in
ACCESSORY mode. The engine may
not start with the engine switch turned off.
However, the engine will operate nor-
mally from the second attempt.
●The engine switch mode is recorded by
the vehicle. If the battery is disconnected
and reconnected, the vehicle will return
the engine switch mode to the status it
was in before the battery was discon-
nected. Make sure to turn off the engine
before disconnecting the battery. Take
extra care when connecting the battery if
the engine switch mode prior to the bat-
tery being disconnected is unknown.
If the system will not start even after multi-
ple attempts, contact your Lexus dealer.
WARNING
■When filling the reservoir
Take care as brake fluid can harm your
hands and eyes and damage painted sur-
faces.If fluid gets on your hands or in your
eyes, flush the affected area with clean
water immediately.
If you still experience discomfort, see a
doctor.
NOTICE
■If the fluid level is low or high
It is normal for the brake fluid level to go
down slightly as the brake pads wear out
or when the fluid level in the accumulator
is high.
If the reservoir need s frequent refilling,
there may be a serious problem.
Battery
A
B

2556-3. Do-it-yourself maintenance
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Maintenance and care
RC300 Check if the treadwear indicators are
showing on the tires. Also check the
tires for uneven wear, such as excessive
wear on one side of the tread.
Check the spare tire condition and
pressure if not rotated.
New tread
Worn tread
Treadwear indicator
The location of treadwear indicators is
shown by a “TWI” or “ ” mark, etc.,
molded into the sidewall of each tire.
Replace the tires if the treadwear indica-
tors are showing on a tire.
WARNING
■When adding washer fluid
Do not add washer fluid when the engine
is hot or running as washer fluid contains
alcohol and may catch fire if spilled on
the engine, etc.
NOTICE
■Do not use any fluid other than
washer fluid
Do not use soapy water or engine anti-
freeze instead of washer fluid.
Doing so may cause streaking on the
vehicle’s painted surfaces, as well as
damaging the pump leading to problems
of the washer fluid not spraying.
■Diluting washer fluid
Dilute washer fluid with water as neces-
sary.
Refer to the freezing temperatures listed
on the label of the washer fluid bottle.
Tires
Replace or rotate tires in accor-
dance with maintenance schedules
and treadwear.
Checking tires
A
B
C

2566-3. Do-it-yourself maintenance
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■When to replace your vehicle’s tires
Tires should be replaced if:
●The treadwear indicators are showing on
a tire.
●You have tire damage such as cuts, splits,
cracks deep enough to expose the fabric,
and bulges indicating internal damage
●A tire goes flat repeatedly or cannot be
properly repaired due to the size or loca-
tion of a cut or other damage
If you are not sure, consult your Lexus
dealer.
■Tire life
Any tire over 6 years old must be checked
by a qualified technician even if it has sel-
dom or never been used or damage is not
obvious.
■Low profile tires
Generally, low profile tires will wear more
rapidly and tire grip performance will be
reduced on snowy and/or icy roads when
compared to standard ti res. Be sure to use
snow tires or tire chains on snowy and/or icy
roads and drive carefully at a speed appro-
priate for road and weather conditions.
■Maximum load of tire
Check that the maximum load of the
replacement tire is greater than 1/2 of the
Gross Axle Weight Ratings (GAWR) of
either the front axle or the rear axle, which-
ever is greater.
For the GAWR, see the Certification Label.
For the maximum load of the tire, see the
load limit at maximum cold tire inflation
pressure mentioned on the sidewall of the
tire. ( P.329)
■Tire types
●Summer tires Summer tires are high-speed performance
tires best suited to
highway driving under
dry conditions. Since summer tires do not
have the same traction performance as
snow tires, summer ti res are inadequate for
driving on snow-covered or icy roads. For
driving on snow-covered roads or icy
roads, the use of snow tires is recom-
mended. When installing snow tires, be
sure to replace all four tires.
●All season tires
All season tires are designed to provide
better traction in snow and to be adequate
for driving in most winter conditions as well
as for use year-round. All season tires,
however, do not have adequate traction
performance compared with snow tires in
heavy or loose snow. Also, all season tires
fall short in accelerati on and handling per-
formance compared with summer tires in
highway driving.
●Snow tires
For driving on snow-covered roads or icy
roads, we recommend using snow tires. If
you need snow tires, select tires of the
same size, construction and load capacity
as the originally instal led tires. Since your
vehicle has radial tires as original equip-
ment, make sure your snow tires also have
radial construction. Do not install studded
tires without first checking local regula-
tions for possible restrictions. Snow tires
should be installed on all wheels. ( P.196)
■If the tread on snow tires wears down
below 0.16 in. (4 mm)
The effectiveness of the tires as snow tires is
lost.

2586-3. Do-it-yourself maintenance
RC350AWD_RC350_RC300AWD_RC30
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If this accidentally oc
curs, either turn the
engine switch to off and then to IGNITION
ON mode, or initialize the system after
checking that the tire pressure is properly
adjusted.
Your vehicle is equipped with a tire
pressure warning system that uses tire
pressure warning valves and transmit-
ters to detect low tire inflation pressure
before serious problems arise.
 If the tire pressure drops below a
predetermined level, the driver is
warned by a screen display and a
warning light. ( P.287)
 The tire pressure detected by the
tire pressure warning system can be
displayed on the multi-information
display. ( P.71)
The illustration used is intended as an
example, and may differ from the image
that is actually displayed on the multi-infor-
mation display.
■Routine tire inflation pressure checks
The tire pressure warning system does not
replace routine tire inflation pressure
checks. Make sure to check tire inflation
pressure as part of your routine of daily
vehicle checks.
■Situations in which the tire pressure
warning system may not operate prop-
erly
●In the following cases, the tire pressure
warning system may not operate prop-
erly.
• If non-genuine Lexus wheels are used.
• A tire has been replaced with a tire that is not an OE (Original Equipment) tire.
• A tire has been replaced with a tire that is not of the specified size.
• Tire chains, etc. are equipped.
• An auxiliary-supported run-flat tire is equipped.
• If a window tint that affects the radio wave signals is installed.
• If there is a lot of snow or ice on the vehi-
cle, particularly around the wheels or
wheel housings.
• If the tire inflation pressure is extremely
higher than the specified level.
• If tires not equipped with tire pressure warning valves and transmitters are used.
• If the ID code on the tire pressure warn- ing valves and transmitters is not regis-
tered in the tire pressure warning
computer.
●Performance may be af fected in the fol-
lowing situations.
• Near a TV tower, electric power plant, gas station, radio stat ion, large display,
airport or other fac ility that generates
strong radio waves or electrical noise
• When carrying a portable radio, cellular
phone, cordless phone or other wireless
communication device
If tire position information is not correctly
displayed due to the radio wave conditions,
the display may be corrected by driving and
changing the radio wave conditions.
●When the vehicle is parked, the time
taken for the warning to start or go off
could be extended.
●When tire inflation pr essure declines rap-
idly for example when a tire has burst, the
warning may not function.
Tire pressure warning system

2616-3. Do-it-yourself maintenance
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Maintenance and care
●After carrying out the initialization proce-
dure, the tire pressure warning light
blinks for 1 minute then stays on after
driving for 20 minutes.
The tire pressure warning valve and
transmitter is equipped with a unique
ID code. When replacing a tire pres-
sure warning valve and transmitter, it is
necessary to register the ID code.
Have the ID code registered by your
Lexus dealer. The recommended cold tire inflation
pressure and tire size are displayed on
the tire and loading information label.
(
P.322)
Tire valve
Tire pressure gauge
WARNING
■When initializing the tire pressure
warning system
Do not operate the ti re pressure warning
reset switch without first adjusting the tire
inflation pressure to the specified level.
Otherwise, the tire pressure warning
light may not come on even if the tire
inflation pressure is low, or it may come
on when the tire inflation pressure is
actually normal.
Registering ID codes
Tire inflation pressure
Checking the specified tire infla-
tion pressure
Inspection and adjustment pro-
cedure
A
B

2626-3. Do-it-yourself maintenance
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1Remove the tire valve cap.
2
Press the tip of the tire pressure
gauge onto the tire valve.
3
Read the pressure using the gauge
gradations.
4
If the tire inflation pressure is not at
the recommended level, adjust the
pressure.
If you add too much air, press the
center of the valve to deflate.
5
After completing the tire inflation
pressure measurem ent and adjust-
ment, apply soapy water to the
valve and check for leakage.
6
Put the tire valve cap back on.
■Tire inflation pressure check interval
You should check tire inflation pressure
every two weeks, or at least once a month.
Do not forget to check the spare.
■Effects of incorrect tire inflation pres-
sure
Driving with incorrect ti re inflation pressure
may result in the following:
●Reduced fuel economy
●Reduced driving comfort and poor han-
dling
●Reduced tire life due to wear
●Reduced safety
●Damage to the drivetrain
If a tire needs frequent inflating, have it
checked by your Lexus dealer.
■Instructions for checking tire inflation
pressure
When checking tire inflation pressure,
observe the following:
●Check only when the tires are cold.
If your vehicle has been parked for at
least 3 hours or has not been driven for
more than 1 mile or 1.5 km, you will get an
accurate cold tire in flation pressure read- ing.
●Always use a tire pressure gauge.
It is difficult to judge if a tire is properly
inflated based only on its appearance.
●It is normal for the ti
re inflation pressure
to be higher after driving as heat is gen-
erated in the tire. Do not reduce tire infla-
tion pressure after driving.
●Never exceed the vehicle capacity
weight.
Passengers and luggage weight should
be placed so that the vehicle is balanced.
WARNING
■Proper inflation is critical to save tire
performance
Keep your tires properly inflated.
If the tires are not properly inflated, the
following conditions may occur which
could lead to an accident resulting in
death or serious injury:
●Excessive wear
●Uneven wear
●Poor handling
●Possibility of blowouts resulting from
overheated tires
●Air leaking from between tire and
wheel
●Wheel deformation and/or tire dam-
age
●Greater possibility of tire damage
while driving (due to road hazards,
expansion joints, sharp edges on the
road, etc.)
NOTICE
■When inspecting and adjusting tire
inflation pressure
Be sure to put the tire valve caps back on.
If a valve cap is not installed, dirt or mois-
ture may get into the valve and cause an
air leak, resulting in decreased tire infla-
tion pressure.

2636-3. Do-it-yourself maintenance
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Maintenance and care
When replacing wheels, care should
be taken to ensure that they are equiv-
alent to those removed in load capac-
ity, diameter, rim width and inset
*.
Replacement wheels are available at
your Lexus dealer.
*: Conventionally referred to as offset.
Lexus does not recommend using the
following:
 Wheels of different sizes or types
 Used wheels
 Bent wheels that have been straight-
ened
■When replacing wheels
The wheels of your vehicle are equipped
with tire pressure warning valves and trans-
mitters that allow the tire pressure warning
system to provide advance warning in the
event of a loss in tire inflation pressure.
Whenever wheels are replaced, tire pres-
sure warning valves an d transmitters must
be installed. ( P.259)
 Use only Lexus wheel nuts and
wrenches designed for use with
your aluminum wheels.
 When rotating, repairing or chang-
ing your tires, check that the wheel
nuts are still tight after driving 1000
miles (1600 km).
 Be careful not to damage the alumi-
num wheels when using tire chains.
 Use only Lexus genuine balance
weights or equivalent and a plastic
or rubber hammer when balancing
your wheels.
Wheels
If a wheel is bent, cracked or heavily
corroded, it should be replaced.
Otherwise, the tire may separate
from the wheel or cause a loss of
handling control.
Wheel selection
WARNING
■When replacing wheels
●Do not use wheels that are a different
size from those recommended in the
Owner’s Manual, as this may result in a
loss of handling control.
●Never use an inner tube in a leaking
wheel which is designed for a tubeless
tire. Doing so may result in an acci-
dent, causing death or serious injury.
NOTICE
■Replacing tire pressure warning
valves and transmitters
●Because tire repair or replacement
may affect the tire pressure warning
valves and transmitters, make sure to
have tires serviced by your Lexus
dealer or other qua lified service shop.
In addition, make sure to purchase
your tire pressure warning valves and
transmitters at your Lexus dealer.
●Ensure that only genuine Lexus wheels
are used on your vehicle.
Tire pressure warning valves and trans-
mitters may not work properly with
non-genuine wheels.
Aluminum wheel precautions

2646-3. Do-it-yourself maintenance
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1Turn the engine switch off.
2 Open the glove box. Lift up the side
with the stay, disconnect the stay
tabs and remove the partition by
pulling horizontally.
3 Press the tabs and remove the filter
cover. 4
Press the tabs and remove the filter
case.
5 Remove the air conditioning filter
from the filter case and replace it
with a new one.
The “ UP” marks shown on the filter
and the filter case sh ould be pointing up.
■Checking interval
Inspect and replace the air conditioning fil-
ter according to the maintenance schedule.
In dusty areas or areas with heavy traffic
flow, early replacement may be required.
(For scheduled maintenance information,
please refer to the “Owner’s Manual Sup-
plement” or “Scheduled Maintenance”.)
■If air flow from the vents decreases dra-
matically
The filter may be clogged. Check the filter
and replace if necessary.
■Air conditioning filt er with deodorizing
function
When fragrances are placed in your vehi-
cle, the deodorizing effect may become
significantly weakened in a short period.
Air conditioning filter
The air conditioning filter must be
changed regularly to maintain air
conditioning efficiency.
Removing the air conditioning
filter