2022 LEXUS RC350 engine coolant

3047-2. Steps to take in an emergency
RC350/RC300 Owner's Manual
full-speed range
■If a message that indicates the malfunc-
tion of radar sensor is displayed
The following systems may be suspended
until the problem shown in the message is
resolved. P.158, 293
●PCS (Pre-Collision System)
■If “Maintenance Required Soon” is dis-
played
Indicates that all maintenance according to
the driven distance on the maintenance
schedule
* should be performed soon.
Comes on approximately 4500 miles
(7200 km) after the message has been
reset. If necessary, perform maintenance.
Please reset the message after the mainte-
nance is performed. ( P.246)
*: Refer to the separate “Scheduled Main-
tenance” or “Owner’s Manual Supple-
ment” for the maintenance interval
applicable to your vehicle.
■If “Maintenance Required Visit Your
Dealer” is displayed
Indicates that all maintenance is required to
correspond to the driven distance on the
maintenance schedule
*.
Comes on approximately 5000 miles
(8000 km) after the message has been
reset. (The indicator will not work properly
unless the message ha s been reset.) Per-
form the necessary maintenance. Please
reset the message after the maintenance is
performed. ( P.246)
*: Refer to the separate “Scheduled Main-
tenance” or “Owner’s Manual Supple-
ment” for the maintenance interval
applicable to your vehicle.
■If “Oil Maintenance Required Soon” is
displayed
Indicates that the engine oil is scheduled to
be changed. (The indicator will not work
properly unless the oil maintenance data
has been reset.)
Check the engine oil, and change if neces-
sary. After changing the engine oil, the oil
change system shou ld be reset. (P.258)
■If “Oil Maintenance Required” is dis-
played
Indicates that the engine oil should be
changed. (After the engine oil is changed
and the oil maintenance data has been
reset.)
Check and change the engine oil, and oil fil-
ter by your Lexus dealer. After changing the
engine oil, the oil change system should be
reset. ( P.258)
■If a message that indicates the need for
visiting your Lexus dealer is displayed
The system or part shown on the
multi-information displa y is malfunctioning.
Have the vehicle inspected by your Lexus
dealer immediately.
■If “See Owner’s Manual” is displayed
●If the following messages are shown, fol-
lowing the instructions, accordingly.
• “Engine Coolant Temp High” ( P.320)
●If any of the following messages are
shown on the multi-information display, it
may indicate a malf unction. Have the
vehicle inspected by your Lexus dealer
immediately.
• “Braking Power Low”
• “Access System with Elec. Key Malfunc- tion”
●If any of the following messages are
shown on the multi-info rmation display, it
may indicate a malfun ction. Immediately
stop the vehicle and contact your Lexus
dealer.
• “Oil Pressure Low”
• “Charging Syst em Malfunction”
NOTICE
■“High Power Consumption Partial
Limit On AC/Heater Operation” is
frequently shown
There is a possible malfunction relating
to the charging system or the battery
may be deteriorating. Have the vehicle
inspected by your Lexus dealer.

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

3217-2. Steps to take in an emergency
RC350/RC300 Owner's Manual
7
When trouble arises
Radiator
Cooling fans
If a large amount of coolant leaks, immedi-
ately contact your Lexus dealer.
RC300
Radiator
Cooling fans
If a large amount of coolant leaks, immedi-
ately contact your Lexus dealer.
4 The coolant level is satisfactory if it
is between the full (“FULL” or “F”)
and low (“LOW” or “L”) lines on the
reservoir.
 Engine (RC350/RC300 AWD) Reservoir cap
“FULL” or “F”
“LOW” or “L”
 Engine (RC300)
Reservoir cap
“FULL” or “F”
“LOW” or “L”
 Intercooler (RC300)
Reservoir cap
“FULL” or “F”
“LOW” or “L”
A
B
A
B
A
B
C
A
B
C
A
B
C

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.

3237-2. Steps to take in an emergency
RC350/RC300 Owner's Manual
7
When trouble arises
WARNING
●RC350/RC300 AWD: While the
engine and radiator are hot, do not
loosen or remove the coolant reser-
voir cap or coolant inlet cap. (The
coolant inlet cap is located under the
engine cover.)
High temperature steam or coolant
could spray out.
●RC300: While the engine and radia-
tors are hot, do not loosen or remove
the coolant reservoir cap, coolant inlet
cap, or intercooler coolant reservoir
cap.
High temperature steam or coolant
could spray out.
NOTICE
■When adding engine coolant
Add coolant slowly after the engine has
cooled down sufficiently. Adding cool
coolant to a hot engine too quickly can
cause damage to the engine.
■To prevent damage to the cooling sys-
tem
Observe the following precautions:
●Avoid contaminating the coolant with
foreign matter (such as sand or dust
etc.).
●Do not use any coolant additive.

3308-1. Specifications
RC350/RC300 Owner's Manual
*: The fluid capacity is a reference quantity.
If replacement is necessary, contact your Lexus dealer.
■Spark plug
Cooling system
Capacity*
RC350/RC3
00 AWD10.0 qt. (9.5 L, 8.4 Imp. qt.)
RC300
Gasoline engine
8.5 qt. (8.0 L, 7.0 Imp. qt.)
Intercooler
3.3 qt. (3.1 L, 2.7 Imp. qt.)
Coolant type
Use either of the following:
 “Toyota Super Long Life Coolant”
 Similar high-quality ethylene glycol-based non-silicate,
non-amine, non-nitrite, and non-borate coolant with
long-life hybrid orga nic acid technology
Do not use plain water alone.
Ignition system (spark plug)
RC350/RC300 AWDRC300
MakeDENSO FK20HBR8NGK DILFR7K9G
Gap0.031 in. (0.8 mm)0.035 in. (0.9 mm)
NOTICE
■Iridium-tipped spark plugs
Use only iridium-tipped spark plugs. Do not adjust the spark plug gap.
Electrical system (battery)
Open voltage at 68°F (20°C):
12.3 V or higher
If the voltage is lower than the standard value,
charge the battery.
(Voltage is checked 20 minutes after the engine
and all lights are turned off.)
Charging rates5 A max.

3438-1. Specifications
RC350/RC300 Owner's Manual
8
Vehicle specifications
cornering (turning) traction.
■Temperature A, B, C
The temperature grades are A (the
highest), B, and C, representing the
tire’s resistance to the generation of
heat and its ability to dissipate heat
when tested under controlled condi-
tions on a specified indoor laboratory
test wheel.
Sustained high temperature can cause the
material of the tire to degenerate and
reduce tire life, and excessive temperature
can lead to sudden tire failure. Grade C corresponds to
a level of perfor-
mance which all passenger car tires must
meet under the Federal Motor Vehicle
Safety Standard No. 109.
Grades B and A represent higher levels of
performance on the laboratory test wheel
than the minimum required by law.
Warning: The temperatur e grades of a tire
assume that it is properly inflated and not
overloaded.
Excessive speed, unde rinflation, or exces-
sive loading, either separately or in combi-
nation, can cause heat buildup and
possible tire failure.
Glossary of tire terminology
Tire related termMeaning
Cold tire inflation pressure
Tire pressure when the vehicle has been parked for
three hours or more, or has not been driven more
than 1 mile or 1.5 km under that condition
Maximum inflation pressureThe maximum cold inflated pressure to which a tire
may be inflated, shown on the sidewall of the tire
Recommended inflation pressureCold tire inflation pressure recommended by a
manufacturer
Accessory weight
The combined weight (in excess of those standard
items which may be replaced) of automatic trans-
mission, power steering, power brakes, power win-
dows, power seats, radio and heater, to the extent
that these items are available as factory-installed
equipment (whether installed or not)
Curb weight
The weight of a motor vehicle with standard equip-
ment, including the maximum capacity of fuel, oil
and coolant, and if so equipped, air conditioning
and additional weight optional engine

387Alphabetical Index
RC350/RC300 Owner's Manual
If the engine will not start ......................... 312
If your vehicle has to be stopped in an
emergency ................................................ 284
Ignition switch (engine switch) .............125
Overheating................................................. 320
Tachometer ..................................................... 66
Engine coolant Capacity .........................................................330
Checking .......................................................258
Preparing and checking before winter......................................................................... 203
Engine coolant temperature gauge ....... 66
Engine immobilizer system ........................ 56
Engine oil Capacity ......................................................... 328
Checking ....................................................... 256
Preparing and checking before winter......................................................................... 203
Warning light ............................................... 294
Engine oil maintenance data .................. 258
Engine oil pressure gauge ...........................74
Engine oil temperature gauge ...................74
Engine switch ..................................................125 Auto power off function ...........................128
Changing the engine switch modes.. 127
If your vehicle has to be stopped in an
emergency ................................................ 284
EPS (Electric Power Steering) ................199 Warning light ............................................... 295
Event data recorder (EDR) ............................7
F
First-aid kit storage belt .............................227
Flat tire Tire pressure warning system ............. 266
Vehicles with a spare tire ..................... 305
Floor mats ...........................................................22
Fluid Automatic transmission ............................331
Brake.................................................... 260, 332
Washer ........................................................... 262
Footwell light ................................................. 223 Front passenger occupant classification
system .............................................................. 36
Front position lights Wattage ..........................................................336
Front seats Adjustment ....................................................... 97
Cleaning ......................................................... 243
Correct driving posture ............................ 23
Driving position memory ........................ 100
Head restraints............................................. 103
Memory recall function............................ 102
Power easy access system .................... 100
Seat heaters .................................................... 221
Seat position memory .............................. 100
Seat ventilators .............................................. 221
Front side marker light Light switch .................................................... 140
Front turn signal lights Replacing light bulbs............................... 280
Turn signal lever ...........................................134
Wattage ..........................................................336
Fuel Capacity .........................................................328
Fuel gauge........................................................ 66
Fuel pump shut off system..................... 292
Information .................................................... 337
Refueling.......................................................... 153
Type ..................................................................328
Warning light ............................................... 297
Fuel consumption Average fuel economy .............................. 73
Current fuel consumption ........................ 73
Fuel filler door If the fuel filler do or cannot be opened
............................................................................314
Refueling.......................................................... 153
Fuel gauge ......................................................... 66
Fuel pump shut off system........................ 292
Fuses ..................................................................276
G
Garage door opener ................................. 230