2021 LEXUS RC350 engine coolant

2546-3. Do-it-yourself maintenance
Light bulbs
( P.281)
•Bulb with same num-
ber and wattage rat-
ing as original
• Phillips-head screw- driver
•Flathead screw- driver
•Wrench
Radiator, con-
denser and inter-
cooler radiator
(  P.262)

Tire inflation pres-
sure ( P.273)• Tire pressure gauge
•Compressed air
source
Washer fluid
( P.264)
• Water or washer
fluid containing anti-
freeze (for winter
use)
• Funnel (used only for adding water or
washer fluid)
WARNING
The engine compartment contains many
mechanisms and fluids that may move
suddenly, become hot, or become elec-
trically energized. To avoid death or seri-
ous injury, observe the following
precautions.
■When working on the engine com-
partment
●Keep hands, clothi ng and tools away
from the moving fans and engine drive
belt.
●Be careful not to touch the engine,
radiator, exhaust manifold, etc. right
after driving as they may be hot. Oil
and other fluids may also be hot.
ItemsParts and tools●Do not leave anything that may burn
easily, such as paper and rags, in the
engine compartment.
●Do not smoke, cause sparks or expose
an open flame to fuel or the battery.
Fuel and battery fumes are flammable.
●Be extremely cautious when working
on the battery. It contains poisonous
and corrosive sulfuric acid.
■When working near the electric cool-
ing fans or radiator grille
Be sure the engine switch is off.
With the engine switch in IGNITION
ON mode, the electric cooling fans may
automatically start to run if the air condi-
tioning is on and/or the coolant tempera-
ture is high. ( P.262)
■Safety glasses
Wear safety glasses to prevent flying or
falling material, fluid spray, etc. from get-
ting in your eyes.
NOTICE
■If you remove the air cleaner filter
Driving with the air cleaner filter
removed may cause excessive engine
wear due to dirt in the air.

2576-3. Do-it-yourself maintenance
6
Maintenance and care
RC350/RC300 AWDFuse boxes ( P.278)
Battery ( P.263)
Engine oil level dipstick ( P.258)
Engine coolant reservoir ( P.260)
Engine oil filler cap ( P.258)
Brake fluid reservoir ( P.262)
Washer fluid tank ( P.264)
Electric cooling fans
Condenser ( P.262)
Radiator ( P.262)
Engine compartment
Components
A
B
C
D
E
F
G
H
I
J

2586-3. Do-it-yourself maintenance
RC300Fuse boxes ( P.278)
Battery ( P.263)
Engine oil level dipstick ( P.258)
Engine oil filler cap ( P.258)
Engine coolant reservoir ( P.260)
Brake fluid reservoir ( P.262)
Washer fluid tank ( P.264)
Electric cooling fans
Condenser ( P.262)
Intercooler radiator ( P.262)
Radiator ( P.262)
Intercooler coolant reservoir ( P.260)
With the engine at operating tempera-
ture and turned off, check the oil level
on the dipstick.
■Checking the engine oil
1 Park the vehicle on level ground.
After warming up the engine and
turning it off, wait more than 5 min-
utes for the oil to drain back into the
bottom of the engine.
A
B
C
D
E
F
G
H
I
J
K
L
Checking and adding the engine
oil

2606-3. Do-it-yourself maintenance
RC300
1 Remove the oil filler cap by turning
it counterclockwise.
2 Add engine oil slowly, checking the
dipstick.
3 Install the oil filler cap by turning it
clockwise.
■Engine oil consumption
A certain amount of engine oil will be con-
sumed while driving. In the following situa-
tions, oil consumption may increase, and
engine oil may need to be refilled in
between oil maintenance intervals.
●When the engine is new, for example
directly after purchasing the vehicle or
after replacing the engine
●If low quality oil or oil of an inappropriate
viscosity is used
●When driving at high engine speeds or
with a heavy load, or when driving while
accelerating or decelerating frequently
●When leaving the engine idling for a long
time, or when driving frequently through
heavy traffic
■After changing the engine oil
The engine oil maintena nce data should be
reset. Perform the following procedures:
1 Select on the multi-information dis-
play. ( P.76)
2 Press the or meter control
switch on the steering wheel to select
“Vehicle Settings” then “Oil Mainte-
nance”. (To confirm setting, press .) 3
Select “Yes” and then press .
4 A message is displayed on the
multi-information display.
The coolant level is satisfactory if it is
between the “FULL” and “LOW” lines
WARNING
■Used engine oil
●Used engine oil contains potentially
harmful contaminants which may
cause skin disorders such as inflamma-
tion and skin cancer, so care should be
taken to avoid prolonged and
repeated contact. To remove used
engine oil from your skin, wash thor-
oughly with soap and water.
●Dispose of used oil and filters only in a
safe and acceptable manner. Do not
dispose of used oil and filters in house-
hold trash, in sewers or onto the
ground. Call your Lexus dealer, ser-
vice station or auto parts store for
information concerning recycling or
disposal.
●Do not leave used engine oil within the
reach of children.
NOTICE
■To prevent serious engine damage
Check the oil level on a regular basis.
■When replacing the engine oil
●Be careful not to spill engine oil on the
vehicle components.
●Avoid overfilling, or the engine could
be damaged.
●Check the oil level on the dipstick
every time you re fill the vehicle.
●Be sure the engine o il filler cap is prop-
erly tightened.
Checking the coolant

2616-3. Do-it-yourself maintenance
6
Maintenance and care
on the reservoir when the engine is
cold.
■Engine coolant reservoir
RC350/RC300 AWD
RC300Reservoir cap
“FULL” line
“LOW” line
If the level is on or below the “LOW” line,
add coolant up to the “FULL” line.
(  P.322)
■Intercooler coolant reservoir
(RC300)
The coolant level is satisfactory if it is
between the “F” and “L” lines on the
reservoir when the engine is cold. Reservoir cap
“F” line
“L” line
If the level is on or
below the “L” line, add
coolant up to the “F” line. ( P.322)
■Coolant selection
Only use “Toyota Super Long Life Coolant”
or a similar high qua lity ethylene glycol
based non-silicate, non-amine, non-nitrite,
and non-borate coolant with long-life
hybrid organic acid technology.
U.S.A.:
“Toyota Super Long Life Coolant” is a mix-
ture of 50% coolant and 50% deionized
water. (Minimum temperature: -31°F
[-35°C])
Canada:
“Toyota Super Long Life Coolant” is a mix-
ture of 55% coolant and 45% deionized
water. (Minimum temperature: -44°F
[-42°C])
For more details about coolant, contact
your Lexus dealer.
■If the coolant level drops within a short
time of replenishing
Visually check the radi ator, hoses, engine
and intercooler coolant reservoir caps,
drain cock and water pump.
If you cannot find a leak, have your Lexus
dealer test the cap and check for leaks in
the cooling system.
A
B
C
A
B
C

2626-3. Do-it-yourself maintenance
Check the radiator, condenser and
intercooler radiator and clear away
any foreign objects.
If any of the above parts are extremely
dirty or you are not sure of their condi-
tion, have your vehicle inspected by
your Lexus dealer.
■Checking fluid level
The brake fluid level should be
between the “MAX” and “MIN” lines
on the tank.
RC350/RC300 AWD
RC300
■Adding fluid
Make sure to check the fluid type and
prepare the necessary item.
 Fluid type
SAE J1703 or FMVSS No.116 DOT 3
brake fluid
SAE J1704 or FMVSS No.116 DOT 4
brake fluid
Item
Clean funnel
WARNING
■When the engine is hot
Do not remove the engine coolant reser-
voir cap, intercooler coolant reservoir
cap and coolant inlet cap. ( P.325)
The cooling system may be under pres-
sure and may spray hot coolant if the cap
is removed, causing serious injuries, such
as burns.
NOTICE
■When adding coolant
Coolant is neither plain water nor
straight antifreeze. The correct mixture
of water and antifreeze must be used to
provide proper lubrication, corrosion
protection and cooling. Be sure to read
the antifreeze or coolant label.
■If you spill coolant
Be sure to wash it off with water to pre-
vent it from damagi ng parts or paint.
Checking the radiator, con-
denser and intercooler radiator
(if equipped)
WARNING
■When the engine is hot
Do not touch the radiator, condenser or
intercooler radiator as they may be hot
and cause serious injuries, such as burns.
Checking and adding the brake
fluid

2937-2. Steps to take in an emergency
7
When trouble arises
Fluid leaks under the vehicle.
(Water dripping from the air condi-
tioning after use is normal.)
 Flat-looking tires or uneven tire
wear
 Engine coolant temperature gauge
continually points higher than nor-
mal.
 Changes in exhaust sound
 Excessive tire squeal when corner-
ing
 Strange noises related to the sus-
pension system
 Pinging or other noises related to
the engine
 Engine missing, stumbling or run-
ning roughly
 Appreciable loss of power
 Vehicle pulls heavily to one side
when braking 
Vehicle pulls heavily to one side
when driving on a level road
 Loss of brake effectiveness, spongy
feeling, pedal almost touches the
floor
If you think something is
wrong
If you notice any of the following
symptoms, your vehicle probably
needs adjustment or repair. Con-
tact your Lexus dealer as soon as
possible.
Visible symptoms
Audible symptoms
Operational symptoms

2957-2. Steps to take in an emergency
7
When trouble arises
■Brake system warning light
■Brake system warning light
■High coolant temperature warning light* (warning buzzer)
*: This light illuminates on the multi-information display.
If a warning light turns on or a warning buzzer sounds
Calmly perform the following actions if any of the warning lights comes on or
flashes. If a light comes on or flashes, bu t then goes off, this does not necessar-
ily indicate a malfunction in the system. However, if this continues to occur,
have the vehicle inspected by your Lexus dealer.
Actions to the warning lights or warning buzzers
Warning lightDetails/Actions
(U.S.A.)
or
(red)
(Canada)
Indicates that:
 The brake fluid level is low; or
 The brake system is malfunctioning
 Immediately stop the vehicle in a safe place and contact your Lexus
dealer. Continuing to drive the vehicle may be dangerous.
Warning lightDetails/Actions
(yellow)
Indicates a malfunction in the parking brake system
 Have the vehicle inspected by your Lexus dealer immediately.
Warning lightDetails/Actions
Indicates that the engine coolant temperature is too high
Immediately stop the vehicle in a safe place.
Handling method ( P.322)