
2646-3. Do-it-yourself maintenance
RC350/RC300 Owner's Manual
■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 tires. 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.339)
■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-cov ered 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 us ing snow tires. If
you need snow tires, select tires of the
same size, construction and load capacity
as the originally installed 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 installe d on all wheels.
( P.203)
■If the tread on snow tires wears down
below 0.16 in. (4 mm)
The effectiveness of the tires as snow tires is
lost.

2676-3. Do-it-yourself maintenance
RC350/RC300 Owner's Manual
6
Maintenance and care
warning valves and transmitters are used.
• If the ID code on the tire pressure warn- ing valves and transm itters is not regis-
tered in the tire pressure warning
computer.
●Performance may be affected in the fol-
lowing situations.
• Near a TV tower, electric power plant,
gas station, radio stat ion, large display,
airport or other faci lity that generates
strong radio waves or electrical noise
• When carrying a portable radio, cellular phone, cordless phon e 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 pressure declines rap-
idly for example when a tire has burst, the
warning may not function.
When replacing the tires or wheels, the
tire pressure warning valve and trans-
mitters must be installed to the wheels
which will be installed to the vehicle.
When new tire pressure warning
valves and transmitte rs are installed,
new ID codes must be registered in the
tire pressure warning computer and
the tire pressure warning system must
be initialized. ( P.269)
■Replacing tires and wheels
If the ID code of the tire pressure warning
valve and transmitter is not registered, the
tire pressure warning system will not work
properly. After driving for about 20 min-
utes, the tire pressure warning light blinks
for 1 minute and stays on to indicate a sys- tem malfunction.
■The tire pressure warning system
must be initialized in the following
circumstances:
When rotating the tires.
When the tire inflation pressure is
changed such as when changing
traveling speed or load weight.
When changing the tire size.
Installing tire pressure warning
valves and transmitters
NOTICE
■Repairing or replac ing tires, wheels,
tire pressure warning valves, trans-
mitters and tire valve caps
●When removing or fitting the wheels,
tires or the tire pressure warning
valves and transmitters, contact your
Lexus dealer as the tire pressure warn-
ing valves and transmitters may be
damaged if not handled correctly.
●Make sure to install the tire valve caps.
If a tire valve cap is not installed, water
may enter the valve and cause it to
corrode, possibly leading to the valve
sticking or air to leak from the tire.
●When replacing tire valve caps, do not
use tire valve caps other than those
specified. The cap may become stuck.
■To avoid damage to the tire pressure
warning valves and transmitters
When a tire is repaired with liquid seal-
ants, the tire pressure warning valve and
transmitter may not operate properly. If a
liquid sealant is used , contact your Lexus
dealer or other qualified service shop as
soon as possible. Afte r use of liquid seal-
ant, make sure to re place the tire pres-
sure warning valve and transmitter when
repairing or replacing the tire. ( P.267)
Initializing the tire pressure
warning system

2726-3. Do-it-yourself maintenance
RC350/RC300 Owner's Manual
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 tire 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.
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 wa rning 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 and transmitters must
be installed. ( P.267)
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 in stalled, dirt or mois-
ture may get into the valve and cause an
air leak, resulting in decreased tire infla-
tion pressure.
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.

2736-3. Do-it-yourself maintenance
RC350/RC300 Owner's Manual
6
Maintenance and careUse 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. 1
Turn 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.
WARNING
●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 qual ified service shop.
In addition, make sure to purchase
your tire pressure warning valves and
transmitters at your Lexus dealer.
●Ensure that only ge nuine 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
Air conditioning filter
The air conditioning filter must be
changed regularly to maintain air
conditioning efficiency.
Removing the air conditioning
filter

2746-3. Do-it-yourself maintenance
RC350/RC300 Owner's Manual
4Press 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 should be pointing up.
■Checking interval
Inspect and replace the air conditioning fil-
ter according to the maintenance schedule.
In dusty areas or area s with heavy traffic
flow, early replacement may be required.
(For scheduled mainte nance information,
please refer to the “Owner’s Manual Sup-
plement” or “Scheduled Maintenance”.)
■If air flow from th e vents decreases dra-
matically
The filter may be clogged. Check the filter
and replace if necessary.
■Air conditioning filter with deodorizing
function
When fragrances are placed in your vehi-
cle, the deodorizing effect may become
significantly weakened in a short period. When an air conditioning odor comes out
continuously, replace the air conditioning
filter.
NOTICE
■When using the air conditioning sys-
tem
Make sure that a filter is always installed.
Using the air conditioning system without
a filter may cause damage to the system.

2997-2. Steps to take in an emergency
RC350/RC300 Owner's Manual
7
When trouble arises
■Brake hold operated indicator (warning buzzer)
■SRS warning light
This warning light sy stem monitors the
airbag sensor assembly, front impact sen-
sors, side impact sensors (door), side
impact sensors (front), side impact sensors
(rear), driver’s seat position sensor, driver’s
seat belt buckle switch, front passenger
occupant classification system, “AIR BAG
ON” indicator light, “AIR BAG OFF” indi-
cator light, front passe nger’s seat belt
buckle switch, seat belt pretensioners,
airbags, interconnect ing wiring and power
sources. ( P.29)
■Front passenger detection sensor, seat
belt reminder and warning buzzer
●If luggage is placed on the front passen-
ger seat, the front passenger detection
sensor may cause the warning light to
flash and the warning buzzer to sound
even if a passenger is not sitting in the
seat.
●If a cushion is placed on the seat, the sen-
sor may not detect a passenger, and the
warning light may not operate properly.
■If the malfunction indicator lamp comes
on while driving
First check the following:
●Is the fuel tank empty?
If it is, fill the fuel tank immediately.
●Is the fuel tank cap loose?
If it is, tighten it securely.
The light will go off after several driving
trips.
If the light does not go off even after several
trips, contact your Lexus dealer as soon as
possible.
■Electric power steering system warning
light (warning buzzer)
When the battery charge becomes insuffi- cient or the voltage temporarily drops, the
electric power steering system warning
light may come on and the warning buzzer
may sound.
■When the tire pressure warning light
comes on
Check the tire inflation pressure and adjust
to the appropriate leve l. Pushing the tire
pressure warning reset switch will not turn
off the tire pressure warning light.
■The tire pressure warning light may
come on due to natural causes
The tire pressure warning light may come
on due to natural causes such as natural air
leaks and tire inflation pressure changes
caused by temperature. In this case, adjust-
ing the tire inflation pressure will turn off the
warning light (after a few minutes).
■When a tire is replaced with the spare
tire
The spare tire is not equipped with a tire
pressure warning valve and transmitter. If a
tire goes flat, the tire pressure warning light
will not turn off even th ough the flat tire has
been replaced with the spare tire.
■Conditions that the tire pressure warn-
ing system may not function properly
P.266
■If the tire pressure warning light fre-
quently comes on after blinking for 1
minute
If the tire pressure warning light frequently
comes on after blinking for 1 minute when
the engine switch is turned to IGNITION
ON mode, have it checked by your Lexus
dealer.
■Warning buzzer
In some cases, the buzzer may not be heard
due to being in a noisy location or audio
sound.
Warning lightDetails/Actions
(flashes)
Indicates a malfunction in the brake hold system
Have the vehicle inspected by your Lexus dealer immediately.

3207-2. Steps to take in an emergency
RC350/RC300 Owner's Manual
1Stop the vehicle in a safe place and
turn off the air conditioning system,
and then stop the engine.
2 If you see steam:
Carefully lift the hood after the
steam subsides.
If you do not see steam:
Carefully lift the hood.
3 After the engine has cooled down
sufficiently, inspect the hoses and
radiator core (radiator) for any
leaks.
RC350/RC300 AWD
WARNING
●When working with the battery, always
wear safety glasses and take care not
to allow any battery fluids (acid) to
come into contact with skin, clothing
or the vehicle body.
●Do not lean over the battery.
●In the event that battery fluid comes
into contact with the skin or eyes,
immediately wash the affected area
with water and seek medical attention.
Place a wet sponge or cloth over the
affected area until medical attention
can be received.
●Always wash your hands after handling
the battery support, terminals, and
other battery-related parts.
●Do not allow children near the battery.
NOTICE
■When handling jumper cables
When connecting the jumper cables,
ensure that they do not become entan-
gled in the cooling fans or engine drive
belt.
If your vehicle overheats
The following may indicate that
your vehicle is overheating.
The engine coolant temperature
gauge ( P.66) is in the red zone
or a loss of engine power is expe-
rienced. (For example, the vehicle
speed does not increase.)
“Engine Coolant Temp High Stop
in a Safe Place See Owner’s
Manual” is shown on the
multi-information display.
Steam comes out from under the
hood.
Correction procedures

3227-2. Steps to take in an emergency
RC350/RC300 Owner's Manual
5Add coolant if necessary.
Water can be used in an emergency if
coolant is unavailable.
Engine (RC350/RC300 AWD)
Engine (RC300)
Intercooler (RC300)
6 Start the engine and turn the air
conditioning system on to check
that the radiator cooling fans oper-
ate and to check for coolant leaks
from the radiator or hoses.
The fans operate when the air conditioning
system is turned on immediately after a
cold start. Confirm that the fans are oper- ating by checking the fan sound and air
flow. If it is difficult to check these, turn the
air conditioning system
on and off repeat-
edly.
(The fans may not operate in freezing tem-
peratures.)
7 If the fans are not operating:
Stop the engine immediately and
contact your Lexus dealer.
If the fans are operating:
Have the vehicle inspected at the
nearest Lexus dealer.
WARNING
■When inspecting under the hood of
your vehicle
Observe the following precautions.
Failure to do so may result in serious
injury such as burns.
●If steam is seen coming from under the
hood, do not open the hood until the
steam has subsided. The engine com-
partment may be very hot.
●Keep hands and clothing (especially a
tie, a scarf or a muff ler) away from the
fans and belts. Failure to do so may
cause the hands or clothing to be
caught, resulting in serious injury.