2021 LEXUS RX450h lane assist

2914-6. Driving tips
4
Driving
Use fluids that are appropriate to
the prevailing outside temperatures.
•Engine oil
• Engine/power control unit coolant
•Washer fluid
Have a service technician inspect
the condition of the 12-volt battery.
 Have the vehicle fitted with four
snow tires or purchase a set of tire
chains for the front tires.
Ensure that all tires ar e of the specified size
and the same brand, and that chains match
the size of the tires.
Perform the following according to the
driving conditions:
 Do not try to forcibly open a window
or move a wiper that is frozen. Pour
warm water over the frozen area to
melt the ice. Wipe away the water
Winter driving tips
Carry out the necessary prepara-
tions and inspections before driving
the vehicle in winter. Always drive
the vehicle in a manner appropriate
to the prevailing weather condi-
tions.
Pre-winter preparations
WARNING
■Driving with snow tires
Observe the following precautions to
reduce the risk of accidents.
Failure to do so may result in a loss of
vehicle control and cause death or seri-
ous injury.
●Use tires of the specified size.
●Maintain the recommended level of air
pressure.
●Do not drive in excess of 75 mph (120
km/h), regardless of the type of snow
tires being used.
●Use snow tires on all, not just some
wheels.
■Driving with tire chains
Observe the following precautions to
reduce the risk of accidents.
Failure to do so may result in the vehicle
being unable to be driven safely, and may
cause death or serious injury.
●Do not drive in excess of the speed
limit specified for the tire chains being
used, or 30 mph (50 km/h), which-
ever is lower.
●Avoid driving on bumpy road surfaces
or over potholes.
●Avoid sudden acceleration, abrupt
steering, sudden br aking and shifting
operations that cause sudden engine
braking.
●Slow down sufficiently before entering
a curve to ensure that vehicle control is
maintained.
●Do not use the LTA (Lane Tracing
Assist) system.
NOTICE
■Repairing or replacing snow tires
Request repairs or replacement of snow
tires from your Lexus dealer or legitimate
tire retailers.
This is because the removal and attach-
ment of snow tires affects the operation
of the tire pressure warning valves and
transmitters.
Before driving the vehicle

4227-2. Steps to take in an emergency
■Rear passengers’ seat belt reminder light*1 (warning buzzer)*2
*1: This light illuminates on the center panel.Regardless of whether or not a rear passenger is present, if the power switch is turned to
ON mode with the rear seat belts unfastened, this light will also illuminate for a certain
period of time.
*2: Rear passengers’ seat belt warning buzzer:
The rear passengers’ seat belt warning buzzer sounds to alert the rear passenger that his or
her seat belt is not fastened. If the seat belt is unfastened, the buzzer sounds intermittently
for a certain period of time, af ter the seat belt is fastened and unfastened and the vehicle
reaches a certain speed.
■Tire pressure warning light
■LTA indicator (warning buzzer)
Warning lightDetails/Actions
(RX450h)
or
(RX450hL)
Warns the rear passengers to fasten their seat belts
 Fasten the seat belt.
Warning lightDetails/Actions
Indicates the following:
Low tire pressure due to flat tire;
 Low tire pressure due to natural causes; or
 The tire pressure warning system is malfunctioning
 Immediately stop the vehicle in a safe place.
Handling method ( P.425)
Warning lightDetails/Actions
(orange)
Indicates a malfunction in th e LTA (Lane Tracing Assist)
 Follow the instructions displayed on the multi-information display.
(  P.235)

4307-2. Steps to take in an emergency
not be charged when the shift lever is in N,
shift the shift lever to P when the vehicle is
stopped.
■If “Traction Battery Needs to be Pro-
tected. Shift into P to Restart.” is dis-
played
This message is displayed when the hybrid
battery (traction battery) charge has
become extremely low because the shift
lever has been left in N for a certain amount
of time.
When operating the vehicle, shift to P and
restart the hybrid system.
■If “Shift Is in N Release Accelerator
Before Shifting” is displayed
Message is displayed when the accelerator
pedal has been depressed and the shift
lever is in N.
Release the accelerator pedal and shift the
shift lever to D or R.
■If “Depress Brake when Vehicle Is
Stopped Hybrid Syst em May Overheat”
is displayed
Message is displayed when the accelerator
pedal is depressed to maintain the vehicle
position when stopped on a upward slope,
etc.
If this continues, th e hybrid system may
overheat.
Release the accelerator pedal and depress
the brake pedal.
■If “Power Turned Off to Save Battery” is
displayed
This message is displayed when the power
was cut off due to the automatic power off
function. The next time the hybrid system is
started, increase the engine speed slightly
and maintain it at that speed for approxi-
mately 5 minutes to recharge the 12-volt
battery.
■If “Headlight System Malfunction Visit
Your Dealer” is displayed
The following systems may be malfunction-
ing. Have the vehicle inspected by your
Lexus dealer immediately.
●The LED headlight system
●AFS (Adaptive Front-lighting System) (if equipped)
●The automatic headlight leveling system
●Automatic High Beam
■If “Radar Cruise Control Unavailable
See Owner's Manual” is displayed
The dynamic radar cruise control with
full-speed range system is suspended tem-
porarily or until the problem shown in the
message is re solved. (causes and coping
methods: P.218)
■If “Radar Cruise Control Unavailable” is
displayed
The dynamic radar cruise control with
full-speed range system cannot be used
temporarily. Use the system when it
becomes available again.
■If a message that indicates the malfunc-
tion of front camera is displayed
The following systems may be suspended
until the problem shown in the message is
resolved. ( P.218, 424)
●PCS (Pre-Collision system)
●LTA (Lane Tracing Assist)
●Automatic High Beam
●RSA (Road Sign Assist) (if equipped)
●Dynamic radar cruise control with
full-speed range
■If “Maintenance Required Soon” is dis-
played (U.S.A. only)
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.362)
*: Refer to the separate “Scheduled Main-
tenance” or “Owner’s Manual Supple-
ment” for the main tenance interval
applicable to your vehicle.
■If “Maintenance Required Visit Your
Dealer” is displayed (U.S.A. only)
Indicates that all mainte nance is required to
correspond to the driven distance on the

4437-2. Steps to take in an emergency
7
When trouble arises
WARNING
• PCS (Pre-Collision System)
• LTA (Lane Tracing Assist)
• RSA (Road Sign Assist) (if equipped)
•Automatic High Beam
• AFS (Adaptive Front-lighting System) (if equipped)
• Tire pressure warning system
• Intuitive parking assist (if equipped)
• PKSB (Parking Support Brake) (if equipped)
• Lexus parking assist monitor (if equipped)
• Panoramic view monitor (if equipped)
• BSM (Blind Spot Monitor) (if equipped)
• Navigation system (if equipped)
Also, not only can the following system
not be utilized fully, but it may even nega-
tively affect the drive-train components:
•E-Four
■Speed limit when using the compact
spare tire
Do not drive at speeds in excess of 50
mph (80 km/h) when a compact spare
tire is installed on the vehicle.
The compact spare tire is not designed
for driving at high speeds. Failure to
observe this precaution may lead to an
accident causing deat h or serious injury.
■After using the tools and jack
Before driving, make sure all the tools
and jack are securely in place in their
storage location to reduce the possibility
of personal injury during a collision or
sudden braking.
NOTICE
■Be careful when driving over bumps
with the compact spare tire installed
on the vehicle
The vehicle becomes lower when driving
with the compact spar e tire compared to
when driving with standard tires. Be
careful when driving over uneven road
surfaces.
■Driving with tire chains and the com-
pact spare tire
Do not fit tire chains to the compact
spare tire. Tire chains may damage the
vehicle body and adversely affect driving
performance.
■When replacing the tires
When removing or fitting the wheels,
tires or the tire pr essure warning valve
and transmitter, contact your Lexus
dealer as the tire pressure warning valve
and transmitter may be damaged if not
handled correctly.
■When stowing the flat tire
(RX450hL)
●Ensure that there is no object caught
between the tire and the vehicle
underbody.
●Securely tighten the spare tire clamp
bolt to hold the spare wheel carrier by
the hook.
●Stow the flat tire in the spare tire loca-
tion. Failure to do so may cause dam-
age to the spare tire carrier. Proper
storage reduces the possibility of injury
in a collision or during sudden braking.
●Have the flat tire repaired and the
spare tire replaced with it as soon as
possible.

4888-2. Customization
■PCS (Pre-Collision System) (P.220)
■LTA (Lane Tracing Assist) ( P.227)
■RSA (Road Sign Assist)* ( P.236)
*:If equipped
FunctionDefault settingCustomized setting
PCS (Pre-Collision System)OnOff—O—
Adjust alert timingMiddleEarly—O—Late
FunctionDefault settingCustomized setting
Lane centering functionOnOff—O—
Steering assist functionOnOff—O—
Alert typeSteering wheel
vibrationBuzzer—O—
Alert sensitivityHighStandard—O—
Vehicle sway warning functionOnOff—O—
Vehicle sway warning sensitiv-
ityStandardHigh—O—Low
FunctionDefault settingCustomized setting
RSA (Road Sign Assist)OnOff—O—
Excess speed notification
methodDisplay onlyNo notification—O—Display and buzzer
Excess speed notification level1 mph (2 km/h)3 mph (5 km/h)—O—5 mph (10 km/h)
Other notifications method
(No-entry notification)Display onlyNo notification—O—Display and buzzer
ABC
ABC
ABC

515Alphabetical Index
DifferentialRear differential oil ....................................465
Dimension ...................................................... 460
Dinghy towing................................................ 183
Display Center Display........................................... 300
Dynamic radar cruise control with full-speed range ...................................... 238
Energy monitor.............................................. 99
Head-up display ........................................... 95
Intuitive parking assist.............................. 255
LTA (Lane Tracing Assist).................... 232
Multi-information display ..........................88
RCTA ................................................................ 261
Warning message..................................... 428
Distance until next engine oil change .... 87
Do-it-yourself maintenance .................... 363
Door courtesy lights .....................................321 Wattage..........................................................468
Door lock Power back door.......................................... 113
Side doors ...................................................... 109
Smart access system with push-button start ..................................................................125
Wireless remote control..........................107
Door pockets ................................................ 328
Doors Automatic door lock ing and unlocking
system ..............................................................112
Door glasses ..................................................153
Door lock warning buzzer ...................... 110
Open door warning buzzer ....................112
Outside rear view mirrors ..................... 150
Rear door child-protectors ......................112
Side doors ...................................................... 109
Drive distance .................................................. 90
Driver’s seat position memory Driving position memory......................... 142
Memory recall function ............................143
Power easy access system ..................... 142
Drive-start control ........................................165 Driving
Break-in tips .................................................. 165
Correct driving posture ............................ 25
Driving mode select switch ................... 281
Hybrid vehicle driving tips ................... 289
Procedures .................................................... 164
Winter drive tips ...........................................291
Driving assist system information ............ 92
Driving information display ........................ 90
Driving position memory............................ 142 Memory recall function.............................143
Power easy access system .....................142
Driving range ................................................... 90
Dynamic radar cruise control with full-speed range ........................................ 238Warning message ..................................... 246
E
ECB (Electronically Controlled Brake Sys-
tem) ................................................................ 283
EDR (Event data recorder) ........................... 8
E-Four .............................................................. 284
Elapsed time ..................................................... 90
Electric motor (traction motor) ................ 66
Electric Power Steering (EPS) .............. 284 Warning light .................................................421
Electronic key ................................................ 106 Battery-saving function.............................126
If the electronic key does not operate properly ....................................................... 447
Replacing the battery ...............................393
Electronic sunshade Jam protection function ........................... 159
Operation ....................................................... 158
Electronically Controlled Brake System (ECB) ............................................................ 283
Emergency flashers ..................................... 410
Emergency, in case of If a warning buzzer sounds.................... 418
If a warning light turns on........................ 418
If a warning message is displayed .....428
If the 12-volt battery is discharged ....449

518Alphabetical Index
High voltage components ....................... 69
Hybrid system precautions ..................... 69
If the hybrid system will not start ........ 444
Overheating.................................................456
Power (ignition) switch............................ 184
Regenerative braking ................................. 67
Starting the hybrid system...................... 184
Hybrid System Indicator......................85, 99
Hybrid transmission....................................... 191 M mode ............................................................193
Paddle shift switches ....................... 192, 193
Hybrid vehicle driving tips ....................... 289
I
I/M test ............................................................ 366
Identification Engine ...............................................................461
Vehicle ............................................................460
If your vehicle has to be stopped in an
emergency ................................................... 410
Ignition switch (power switch) ................ 184 Auto power off function ...........................187
Changing the power switch modes ..187
If your vehicle has to be stopped in an
emergency ................................................. 410
Immobilizer system .........................................73
Indicators ........................................................... 80
Initialization Items to initialize ......................................... 493
Maintenance .................................... 362, 373
Power windows............................................153
Tire pressure warning system ............ 385
Inside rear view mirror ................................149
Instrument panel light control ................... 87
Interior lights....................................................321 Front interior light ........................................ 321
Rear interior light ......................................... 321
Intuitive parking assist.....................253, 255 Function .......................................................... 255
Warning message..................................... 257
J
JackPositioning a floor jack ........................... 369
Vehicle-equipped jack ...........................433
Jack handle .................................................... 433
Jam protection function Electronic sunshade .................................. 159
Moon roof ...................................................... 156
Panoramic moon roof .............................. 159
Power back door.......................................... 119
Power windows ........................................... 153
Rear seats ........................................................132
K
Keyless entrySmart access system with push-button start ................................................................. 125
Wireless remote control ......................... 107
Keys Battery-saving function.............................126
Electronic key ............................................... 106
If the electronic key does not operate properly ....................................................... 447
If you lose your keys .................................446
Key number plate ....................................... 106
Keyless entry ....................................... 107, 125
Mechanical key ............................................ 106
Power switch................................................. 184
Replacing the battery ...............................393
Warning buzzer .......................................... 125
Wireless remote control ......................... 107
Knee airbags .................................................... 30
L
Lane Tracing Assist (LTA) Operation ...................................................... 227
Warning messages...................................235
Language (multi-information display) ... 92
LATCH anchors ............................................. 54

519Alphabetical Index
LeverAuxiliary catch lever .................................369
Hood lock release lever.........................369
Shift lever........................................................... 191
Turn signal lever ...........................................194
Wiper lever...................................................206
Lexus climate concierge .......................... 303
Lexus Enform Safety Connect.................. 60
Lexus Safety System + 2.0 AHB (Automatic High Beam)............ 203
Dynamic radar cruise control with full-speed range ...................................... 238
LTA (Lane Tracing Assist).....................227
PCS (Pre-Collision System)................ 220
RSA (Road Sign Assist) ......................... 236
License plate lights Light switch ...................................................200
Replacing light bulbs............................... 400
Light bulbs Replacing .......................................................399
Lights Automatic High Beam system............ 203
Fog light switch ...........................................206
Front interior lights ...................................... 321
Front personal lights................................. 322
Headlight switch ........................................200
Interior lights................................................... 321
Interior lights list............................................ 321
Rear interior lights ....................................... 321
Rear personal lights.................................. 322
Replacing light bulbs............................... 400
Turn signal lever ...........................................194
Vanity lights .................................................. 345
Wattage..........................................................468
Lock steering column ................................. 185
LTA (Lane Tracing Assist) Operation.......................................................227
Warning messages .................................. 235
Luggage cover ............................................. 330M
Maintenance Do-it-yourself maintenance ................. 367
General maintenance .............................363
Maintenance data ..................................... 460
Maintenance requirements ..................362
Malfunction indicator lamp .......................419
Master warning light .................................. 425
Menu icons........................................................ 89
Meter Clock...................................................................83
Hybrid System Indicator ...........................85
Indicators.......................................................... 80
Instrument panel light control................. 87
Meter control switches ..............................89
Meters.................................................................83
Multi-information display ......................... 88
Settings............................................................... 92
Units.......................................................................91
Warning lights .............................................. 418
Warning message .....................................428
Micro dust and pollen filter ........................ 311
Mirrors Inside rear view mirror ............................. 149
Outside rear view mirror defoggers306
Outside rear view mirrors...................... 150
Vanity mirrors ..............................................345
Moon roof Door lock linked moon roof operation........................................................................... 156
Door lock linked panoramic moon roof operation ..................................................... 159
Jam protection function ........................... 156
Operation ....................................................... 155
Multi-information display ............................ 88 Audio system-linked display ................... 92
AWD Control ..................................................91
Drive information ..........................................90
Driving assist system information ......... 92
Driving information display ......................90