2021 LEXUS RX450h cruise control

2424-5. Using the driving support systems
signal lever is operated in the opposite direction to the overtaking lane (e.g., if the driver
normally operates the vehicle in a region where the overtaking lane is to the right but then
drives to a region where the overtaking lane is to the left, the vehicle may accelerate when
the right turn signal is activated).
Example of acceleration
When there are no longer any preceding vehicles driving slower than the set
speed
The system accelerates until the set speed is re ached. The system then returns to constant
speed cruising.
1 Press the “ON/OFF” button to acti-
vate the cruise control.
Dynamic radar cruise control indicator will
come on and a message will be displayed
on the multi-information display. Press the
button again to deactivate the cruise con-
trol.
If the “ON/OFF” button is pressed and
held for 1.5 seconds or more, the system
turns on in constant speed control mode.
( P.245)
2 Accelerate or decelerate, with
accelerator pedal operation, to the
desired vehicle speed (at or above
approximately 20 mph [30 km/h])
and push the lever down to set the
speed.
Cruise control “SET” indicator will come
on. The vehicle speed at the moment the lever
is released beco
mes the set speed.
To change the set speed, operate the
lever until the desired set speed is dis-
played.
1Increases the speed (Except when
the vehicle has been stopped by
system control in vehicle-to-vehi-
cle distance control mode)
2 Decreases the speed
Fine adjustment: Mo mentarily move the
C
Setting the vehicle speed (vehi-
cle-to-vehicle distance control
mode)
Adjusting the set speed

2444-5. Using the driving support systems
After the vehicle ahead of you starts
off, push the lever up.
Your vehicle will also resume follow-up
cruising if the accelerator pedal is
depressed after the vehicle ahead of
you starts off.
1Pulling the lever toward you can-
cels the speed control.
The speed control is also canceled when
the brake pedal is depressed. (When the
vehicle has been stopped by system con-
trol, depressing the brake pedal does not
cancel the setting.)
2Pushing the lever up resumes the
cruise control and returns vehicle
speed to the set speed.
When your vehicle is too close to a
vehicle ahead, and sufficient automatic
deceleration via the cruise control is
not possible, the display will flash and
the buzzer will sound to alert the driver.
An example of this would be if another
driver cuts in front of you while you are
following a vehicle. Depress the brake
pedal to ensure an appropriate vehi-
cle-to-vehicle distance.
■Warnings may not occur when
In the following instances, warnings
may not occur even when the vehi-
cle-to-vehicle distance is small.
 When the speed of the preceding
vehicle matches or exceeds your
vehicle speed
 When the preceding vehicle is trav-
eling at an extremely slow speed
 Immediately after the cruise control
speed was set
 When depressing the accelerator
Resuming follow-up cruising
when the vehicle has been
stopped by system control (vehi-
cle-to-vehicle distance control
mode)
Canceling and resuming the
speed control
Approach warning (vehi-
cle-to-vehicle distance control
mode)

2454-5. Using the driving support systems
4
Driving
pedal
When constant speed control mode is
selected, your vehicle will maintain a
set speed without controlling the vehi-
cle-to-vehicle distance. Select this
mode only when vehicle-to-vehicle dis-
tance control mode does not function
correctly due to a dirty radar, etc.
1 With the cruise control off, press
and hold the “ON/ OFF” button for
1.5 seconds or more.
Immediately after the “ON/OFF” button is
pressed, the dynamic radar cruise control
indicator will come on. Afterwards, it
switches to the cruise control indicator.
Switching to constant speed control mode
is only possible when operating the lever
with the cruise control off.
2 Accelerate or decelerate, with
accelerator pedal operation, to the
desired vehicle speed (at or above
approximately 20 mph [30 km/h])
and push the lever down to set the
speed.
Cruise control “SET” indicator will come
on.
The vehicle speed at the moment the lever
is released becomes the set speed.
Adjusting the sp eed setting: P.242 Canceling and resuming the speed setting:

P.244
■Dynamic radar cruise control with
full-speed range can be set when
●The shift lever is in D.
●The desired set spee d can be set when
the vehicle speed is approximately 20
mph (30 km/h) or more.
(However, when the vehicle speed is set
while driving at belo w approximately 20
mph [30 km/h], the se t speed will be set
to approximately 20 mph [30 km/h].)
■Accelerating after setting the vehicle
speed
The vehicle can accelerate by operating the
accelerator pedal. After accelerating, the
set speed resumes. Ho wever, during vehi-
cle-to-vehicle distance control mode, the
vehicle speed may decrease below the set
speed in order to main tain the distance to
the preceding vehicle.
■When the vehicle stops while follow-up
cruising
●Pushing the lever up while the vehicle
ahead stops will resu me follow-up cruis-
ing if the vehicle ahead starts off within
approximately 3 seconds after the lever
is pushed up.
●If the vehicle ahead starts off within 3 sec-
onds after your vehicle stops, follow-up
cruising will be resumed.
■Automatic cancelation of vehi-
cle-to-vehicle dist ance control mode
Vehicle-to-vehicle distance control mode is
automatically canceled in the following situ-
ations.
●VSC is activated.
Selecting constant speed con-
trol mode

2464-5. Using the driving support systems
●TRAC is activated for a period of time.
●When the VSC or TRAC system is
turned off.
●The sensor cannot detect correctly
because it is covered in some way.
●Pre-collision braking is activated.
●The parking brake is operated.
●The vehicle is stopped by system control
on a steep incline.
●The following are detected when the
vehicle has been stopped by system con-
trol:
• The driver is not wearing a seat belt.
• The driver’s door is opened.
• The vehicle has been stopped for about 3 minutes.
If vehicle-to-vehicle distance control mode
is automatically canceled for any reasons
other than the above, there may be a mal-
function in the system . Contact your Lexus
dealer.
■Automatic cancelation of constant
speed control mode
Constant speed control mode is automati-
cally canceled in the following situations:
●Actual vehicle speed is more than
approximately 10 mph (16 km/h) below
the set vehicle speed.
●Actual vehicle speed falls below approxi-
mately 20 mph (30 km/h).
●VSC is activated.
●TRAC is activated for a period of time.
●When the VSC or TRAC system is
turned off.
●Pre-collision braking is activated.
If constant speed cont rol mode is automati-
cally canceled for any reasons other than
the above, there may be a malfunction in the
system. Contact your Lexus dealer.
■Brake operation
A brake operation sound may be heard and
the brake pedal respon se may change, but
these are not malfunctions.
■Warning messages and buzzers for
dynamic radar cruise control with
full-speed range
Warning messages and buzzers are used to
indicate a system malfunction or to inform
the driver of the need for caution while driv-
ing. If a warning messa ge is shown on the
multi-information displa y, read the message
and follow the instructions.( P.218,428)
■When the sensor may not be correctly
detecting the vehicle ahead
In the case of the fo llowing and depending
on the conditions, operate the brake pedal
when deceleration of the system is insuffi-
cient or operate the accelerator pedal
when acceleration is required.
As the sensor may not be able to correctly
detect these types of vehicles, the approach
warning ( P.244) may not be activated.
●Vehicles that cut in suddenly
●Vehicles traveling at low speeds
●Vehicles that are not moving in the same
lane
●Vehicles with small rear ends (trailers
with no load on board, etc.)
●Motorcycles traveling in the same lane
●When water or snow thrown up by the
surrounding vehicles hinders the detect-
ing of the sensor
●When your vehicle is pointing upwards
(caused by a heavy load in the luggage
compartment, etc.)

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

4427-2. Steps to take in an emergency
7Confirm it is not loose after tighten-
ing:
1 Push and pull the tire
2 Try rotating
Visually check to ensure tire is not hung on
surrounding parts.
If looseness or misassembly exists, repeat
steps 2 to 7.
8 Repeat step 7, any time the tire is
lowered or disturbed.
9 Stow the jack and all tools.
■The compact spare tire
●The compact spare tire is identified by the
label “TEMPORARY USE ONLY” on
the tire sidewall. Use the compact spare
tire temporarily, and only in an emer-
gency.
●Make sure to check the tire inflation pres-
sure of the compact spare tire. ( P.466)
■When using the compact spare tire
As the compact spare tire is not equipped
with a tire pressure warning valve and trans-
mitter, low inflation pressure of the spare
tire will not be indicated by the tire pressure
warning system. Also, if you replace the
compact spare tire after the tire pressure
warning light comes on, the light remains
on.
■When the compact spare tire is
equipped
When driving with the compact spare tire
installed, the vehicle he ight will be different
than when driving with standard tires.
■If you have a flat front tire on a road cov-
ered with snow or ice
Install the compact spare tire on one of the
rear wheels of the vehicle. Perform the fol-
lowing steps and fit tire chains to the front
tires:
1 Replace a rear tire with the compact
spare tire.
2 Replace the flat front tire with the tire
removed from the rear of the vehicle.
3 Fit tire chains to the front tires.
WARNING
■When using the compact spare tire
●Remember that the compact spare tire
provided is specific ally designed for
use with your vehicle. Do not use your
compact spare tire on another vehicle.
●Do not use more than one compact
spare tire simultaneously.
●Replace the compact spare tire with a
standard tire as soon as possible.
●Avoid sudden acceleration, abrupt
steering, sudden br aking and shifting
operations that cause sudden engine
braking.
■When the compact spare tire is
attached
The vehicle speed may not be correctly
detected, and the following systems may
not operate correctly:
• ABS & Brake assist
•VSC
•TRAC
• Trailer Sway Control
•EPS
•VDIM
• Adaptive Variable Suspension System (if equipped)
• Dynamic radar cruise control with full-speed range

514Alphabetical Index
BrakeBrake hold...................................................... 198
Fluid ......................................................375, 465
Parking brake ............................................... 195
Regenerative braking ................................. 67
Warning light ................................................ 418
Brake assist .................................................... 283
Break-in tips.....................................................165
Brightness control Instrument panel light control ................ 87
BSM (Blind Spot Monitor)........................247
Buzzer Hands off steering wheel warning (LTA)......................................................................... 234
C
Care Exterior ...........................................................356
Interior .............................................................359
Seat belts........................................................359
Wheels and wheel ornaments............356
Cargo capacity..................................... 169, 172
Cargo hooks ................................................. 329
Cargo net hooks .......................................... 329
Center Display .............................................300
Chains .............................................................. 292
Child restraint system Fixed with a LATCH system .................. 54
Fixed with a seat belt...................................50
Front passenger occupant classification system ............................................................. 39
Points to remember .................................... 45
Riding with children ..................................... 45
Types of child restraint system installation method ........................................................... 46
Using an anchor bracket .......................... 57
Child safety 12-volt battery precautions .......378, 453
Airbag precautions...................................... 36
Child restraint system................................. 46
Heated steering wheel and seat heater precautions................................................. 318 How your child should wear the seat belt
............................................................................. 27
Moon roof precautions.............................157
Panoramic moon roof precautions ... 160
Power back door precautions ............... 113
Power window lock switch .................... 155
Power window precautions .................. 154
Rear door child-protectors ..................... 112
Seat belt extender precautions.............. 27
Seat belt precautions .................................. 45
Child-protectors............................................. 112
Cleaning Exterior........................................................... 356
Interior ............................................................ 359
Radar sensor ..................................................214
Seat belts ....................................................... 359
Wheels and wheel ornaments ........... 356
Clock ........................................................83, 343
Coat hooks..................................................... 343
Coin box.......................................................... 328
Compass ......................................................... 352
Condenser ..................................................... 374
Console box .................................................. 326
Cooling system............................................. 373 Engine overheating...................................454
Hybrid system overheating ................. 456
Cornering lights ........................................... 202 Replacing light bulbs ............................... 400
Cruise control Dynamic radar cruise control with full-speed range ......................................238
Cup holders ................................................... 327
Current fuel consumption .......................... 90
Curtain shield airbags .................................. 30
Customizable features ..............................480
D
Daytime running light system .................200
Defogger Outside rear view mirrors.................... 306
Rear window ............................................... 306
Windshield ................................................... 306

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