2022 LEXUS RC350 coolant temperature

2937-2. Steps to take in an emergency
RC350/RC300 Owner's Manual
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 followin g 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.320)

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

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.

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

394Alphabetical Index
RC350/RC300 Owner's Manual
Driving mode select switch ....................196
M mode ............................................................ 132
Paddle shift switches ......................... 131, 132
Snow mode ..................................................... 131
Trip meters ........................................................ 70
Trunk .................................................................... 89 Smart access system with push-button start ................................................................... 90
Trunk features...............................................227
Trunk grip ........................................................... 91
Trunk light........................................................... 91
Trunk opener main switch ....................... 92
Trunk opener switch ................................... 90
Wireless remote control............................. 91
Trunk light ............................................................ 91
Turn signal lights Replacing light bulbs................................280
Turn signal lever ...........................................134
Wattage.......................................................... 336
V
Vanity lights.................................................... 229
Vanity mirrors ............................................... 229
Variable Gear Ratio Steering (VGRS)199
VDIM (Vehicle Dynamics Integrated Man-agement)........................................................199
Vehicle data recording ....................................6
Vehicle Dynamics Integrated Manage- ment (VDIM)................................................199
Vehicle identification number ................ 326
Vehicle Stability Control (VSC) ............ 198
Vehicle sway warning display ....................75
Ventilators (seat ventilators)..................... 221
VGRS (Variable Gear Ratio Steering)199
VSC (Vehicle Stabilit y Control) ............ 198
W
Warning buzzer
Open door warning................................. 297
Warning buzzers Approach warning...................................... 179 Brake hold .....................................................299
Brake Override System .........................295
Downshifting ....................................... 132, 133
Drive-Start Control...................................295
Electric power steering...........................295
High coolant temperature.....................293
LDA (Lane Departure Alert with steering
control) ..........................................................167
LDA (Lane Departure Alert) ...............296
Low engine oil pressure.........................294
Open door ............................................. 87, 88
Open window .................................................. 111
Pre-collision braking ................................... 161
Seat belt .......................................................... 297
Warning lights............................................... 293 ABS...................................................................295
Brake hold operated in dicator ...........299
Brake Override System .........................295
Brake system................................................293
Charging system........................................ 294
Drive-Start Control...................................295
Electric power steering...........................295
High coolant temperature.....................293
LDA indicator ..............................................296
Low engine oil pressure.........................294
Low fuel level ............................................... 297
Malfunction indicator lamp ................... 294
Master warning light................................ 298
Open door warning ................................. 297
Parking brake indicator ......................... 298
Pre-collision system..................................296
Seat belt reminder light........................... 297
Slip indicator.................................................296
SRS .................................................................... 294
Tire pressure ............................................... 298
Warning message display............................76
Warning messages ...................................... 301
Washer Checking ....................................................... 262
Preparing and checking before winter..........................................................................203
Switch................................................................ 145