2021 LEXUS RX450h brake

510What to do if... (Troubleshooting)
1-1.What to do if... (Troubleshooting)What to do if... (Troubleshooting)
If you lose your mechanical keys,
new genuine mechanical keys can
be made by your Lexus dealer.
( P.446)
 If you lose your electronic keys, the
risk of vehicle theft increases signifi-
cantly. Contact your Lexus dealer
immediately. ( P.446)
 Is the electronic key battery weak or
depleted? ( P.393)
 Is the power switch in ON mode?
When locking the doors, turn the power
switch off. ( P.187)
 Is the electronic key left inside the
vehicle?
When locking the doors, make sure that
you have the electronic key on your per-
son.
The function may not operate prop- erly due to the condition of the radio
wave. (
P.126)
 Is the child-protector lock set?
The rear door cannot be opened from
inside the vehicle when the lock is set.
Open the rear door from outside and then
unlock the child-protector lock. ( P.112)
 Did you press the power switch
while firmly depressing the brake
pedal? ( P.184)
 Is the shift lever in P? ( P.184)
 Is the electronic key anywhere
detectable inside the vehicle?
( P.125)
 Is the steering wheel unlocked?
( P.185)
 Is the electronic key battery weak or
depleted?
In this case, the hy brid system can be
started in a temporary way. ( P.448)
 Is the 12-volt battery discharged?
( P.449)
 Is the power switch in ON mode?
If you have a problem, check the
following before contacting your
Lexus dealer.
The doors cannot be locked,
unlocked, opened or closed
You lose your keys
The electronic key does not
operate properly
The doors cannot be locked or
unlocked
The rear door cannot be opened
If you think something is wrong
The hybrid system does not start
The shift lever cannot be shifted
from P even if you depress the
brake pedal

511What to do if... (Troubleshooting)
If you cannot release the shift lever by
depressing the brake pedal with the power
switch in ON mode (P.192)
It is locked automatically to prevent
theft of the vehicle. ( P.185)
 Is the window lock switch pressed?
The power window except for the one at
the driver’s seat cannot be operated if the
window lock switch is pressed. ( P.155)
 The auto power off function will be
operated if the vehicle is left in
ACCESSORY or ON mode (the
hybrid system is not operating) for a
period of time. ( P.187)
 The seat belt reminder light is flash-
ing
Are the driver and the passengers wearing
the seat belts? ( P.421)
 The parking brake indicator is on
Is the parking brake released? ( P.195)
Depending on the situation, other
types of warning buzzer may also
sound. ( P.418, 428) 
Did anyone inside the vehicle open
a door during setting the alarm?
The sensor detects it and the alarm sounds.
( P.75)
Do one of the following to stop the
alarms:
 Unlock the doors.
 Turn the power switch to ACCES-
SORY or ON mode, or start the
hybrid system.
 Is the message displayed on the
multi-information display?
Check the message on the multi-informa-
tion display. ( P.428)
 When a warning light turns on or a
warning message is displayed, refer
to P.418, 428.
 Stop the vehicle in a safe place and
replace the flat tire with the spare
tire. ( P.432)
The steering wheel cannot be
turned after the hybrid system is
stopped
The windows do not open or
close by operating the power
window switches
The power switch is turned off
automatically
A warning buzzer sounds during
driving
An alarm is activated and the
horn sounds
A warning buzzer sounds when
leaving the vehicle
A warning light turns on or a
warning message is displayed
When a problem has occurred
If you have a flat tire

513Alphabetical Index
Alphabetical Index
A
A/CAir conditioning filter ...............................390
Front automatic air conditioning system.........................................................................304
Front seat concentr ated airflow mode
(S-FLOW)................................................... 312
Micro dust and pollen filter...................... 311
Rear automatic air conditioning system ...........................................................................315
ABS (Anti-lock Brake System).............. 283 Warning light ............................................... 420
ACA (Active Cornering Assist) ........... 284
Active Cornering Assist (ACA) ........... 284
Adaptive Front-lighting System (AFS)202
Adaptive Variable Suspension System284
AFS (Adaptive Front-lighting System)202
AHB (Automatic High Beam) ............... 203
Air conditioning filter ................................. 390
Air conditioning system Air conditioning filter ...............................390
Front automatic air conditioning system.........................................................................304
Front seat concentr ated airflow mode
(S-FLOW)................................................... 312
Micro dust and pollen filter...................... 311
Rear automatic air conditioning system ...........................................................................315
Airbags Airbag operating conditions................... 33
Airbag precautions for your child ........ 36
Correct driving posture ............................ 25
Curtain shield airbag operating condi- tions .................................................................. 33
Curtain shield airbag precautions ....... 36
Front passenger occupant classification system ............................................................. 39
General airbag precautions ................... 36
Locations of airbags.................................... 30
Modification and disposal of airbags . 38
Side airbag operating conditions ......... 33 Side airbag precautions ............................ 36
Side and curtain shie
ld airbags operating
conditions ...................................................... 33
Side and curtain shield airbags precau- tions .................................................................. 36
SRS airbags......................................................30
SRS warning light.......................................420
Alarm ................................................................... 75 Warning buzzer .......................................... 418
Anchor brackets ..................................... 46, 57
Antennas (smart acc ess system with
push-button start).......................................125
Anti-lock Brake System (ABS).............. 283 Warning light ...............................................420
Approach warning...................................... 244
Armrest............................................................ 342
Assist grips ..................................................... 342
Audio system-linked display ...................... 92
Automatic headlight leveling system ....201
Automatic High Beam .............................. 203
Automatic light control system..............200
Auxiliary boxes ................................... 329, 331
Average fuel economy................................. 90
Average vehicle speed ................................ 90
AWD Control.................................................... 91
B
Back door .......................................................... 113
Back-up light Wattage ......................................................... 468
Back-up lights Replacing light bulbs ...................400, 406
Battery (12-volt battery) Battery checking ........................................ 376
If the 12-volt battery is discharged ....449
Preparing and checking before winter............................................................................291
Warning light ................................................ 419
Battery (traction batter y) ............................ 69
Blind Spot Monitor (BSM)........................247
Bottle holders ................................................ 328

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

516Alphabetical Index
If the electronic key does not operate properly....................................................... 447
If the fuel filler door cannot be opened ......................................................................... 446
If the hybrid system will not start ........ 444
If the vehicle is trapped in rising water411
If you have a flat tire .................................. 432
If you lose your keys................................. 446
If you think something is wrong ........... 417
If your vehicle becomes stuck............. 457
If your vehicle has to be stopped in an
emergency ................................................. 410
If your vehicle needs to be towed ....... 413
If your vehicle overheats ........................ 454
Energy monitor ..................................... 99, 100
Engine ACCESSORY mode ...............................187
Compartment ............................................... 371
Engine switch................................................ 184
Hood................................................................369
How to start the hybrid system ........... 184
Identification number .................................461
If the hybrid system will not start ........ 444
If your vehicle has to be stopped in an
emergency ................................................. 410
Ignition switch (power switch) ............. 184
Overheating................................................. 454
Power switch ................................................ 184
Tachometer ..................................................... 83
Engine coolant Capacity ......................................................... 464
Checking ....................................................... 373
Preparing and checking before winter........................................................................... 291
Engine coolant temperature gauge ....... 83
Engine oil Capacity ......................................................... 463
Checking ......................................................... 371
Preparing and checking before winter........................................................................... 291
Warning light .................................................419
Engine oil maintenance data .................. 373 Engine switch (power switch) ................. 184
If your vehicle has to be stopped in an emergency .................................................. 410
EPS (Electric Power Steering) .............. 284 Warning light .................................................421
EV drive mode............................................... 189
EV indicator .......................................................67
Event data recorder (E DR) ........................... 8
F
Flat tire
Tire pressure warning system .............382
Vehicles with a spare tire....................... 432
Floor mats .......................................................... 24
Fluid Brake ............................................................... 465
Hybrid transmission................................. 465
Washer ...........................................................375
Fog lights Switch.............................................................. 206
Footwell light ...................................................321
Front automatic air conditioning system .......................................................................... 304
Front fog lights Replacing light bulbs ............................... 400
Front passenger footwell hooks ............ 345
Front passenger occupant classification system .............................................................. 39
Front seats Adjustment ....................................................... 131
Cleaning ........................................................ 359
Correct driving posture ............................ 25
Driving position memory .........................142
Head restraints............................................. 145
Memory recall function.............................143
Power easy access system .....................142
Seat heaters ................................................... 318
Seat position memory ...............................142
Seat ventilators ............................................. 318
Front side marker light Light switch .................................................. 200
Replacing light bulbs ............................... 400

520Alphabetical Index
Dynamic radar cruise control with full-speed range ...................................... 238
Energy monitor............................................ 100
G-force................................................................ 91
LTA (Lane Tracing Assist).................... 232
Menu icons ...................................................... 89
Meter control switches .............................. 89
Navigation system-linked display ........ 92
Pop-up display...............................................88
Settings .............................................................. 92
Suggestion function..................................... 93
Tire pressure ................................................ 382
Units ...................................................................... 91
Warning message..................................... 428
N
Navigation system-linked display....92, 98
Noise from under vehicle ...............................6
O
“ODO TRIP” switch ...................................... 87
Odometer ......................................................... 87
Odometer and trip meter display Display items ................................................... 87
“ODO TRIP” switch .................................... 87
Pop-up display............................................... 87
Oil Engine oil ....................................................... 463
Rear differential oil ....................................465
Opener Fuel filler door..................................................211
Hood................................................................369
Outer foot lights Location............................................................ 321
Outside door handle lights........................321
Outside rear view mirrors Adjustment..................................................... 150
BSM (Blind Sport Monitor) ................. 247
Folding ............................................................... 151
Linked mirror functi on when reversing
.......................................................................... 150 Mirror position memory ...........................142
Outside rear view mirror defoggers306
RCTA function ..............................................261
Outside temperature.................................... 83
Overheating .................................................. 454
P
Paddle shift switches ..........................192, 193
Panic mode ......................................................107
Panoramic moon roof Jam protection function ........................... 159
Operation ....................................................... 158
Parking assist sensors (intuitive parking assist) ............................................................. 255
Parking brake Operation ....................................................... 195
Parking brake engaged warning buzzer............................................................................197
Warning light ............................................... 424
Warning message .......................................197
Parking lights Light switch .................................................. 200
Replacing light bulbs ............................... 400
Parking Support Brake function (for rear-crossing vehicles) ...........................277Function .......................................................... 277
Parking Support Brake function (static objects) ........................................................... 271Function ............................................................ 271
PCS (Pre-Collision System) Function ..........................................................220
PCS OFF switch ........................................ 222
Warning light ............................................... 424
Personal lights.................................................321
PKSA (Parking Support Alert) .............. 253
PKSB (Parking Support Brake)............. 266 Warning message ..................................... 270
Power back door ............................................ 113 Hands Free Power Back Door ............. 116
Smart access system with push-button start ................................................................... 114
Power control unit.......................................... 69

522Alphabetical Index
Cleaning and maintaining the seat belt.........................................................................359
Emergency Locking Retractor .............. 28
How to wear your seat belt ......................27
How your child should wear the seat belt .............................................................................27
Pregnant women, proper seat belt use ............................................................................ 26
Reminder light and buzzer ......... 421, 422
Seat belt extender .........................................27
Seat belt pretensioners .............................. 29
SRS warning light ...................................... 420
Seat heaters .................................................... 318
Seat position memory.................................. 142
Seat ventilators .............................................. 318
Seating capacity............................................. 172
Seats Adjustment............................................. 131, 133
Adjustment precautions .................. 131, 132
Child seats/child restraint system installa-tion .................................................................... 45
Cleaning.........................................................359
Driving position memory......................... 142
Folding down the rear seatbacks........133
Head restraints .............................................145
Power easy access system ..................... 142
Properly sitting in the seat ........................ 25
Seat heaters ................................................... 318
Seat position memory ............................... 142
Seat ventilators............................................. 318
Sensor Automatic headlight system.................200
Automatic High Beam system............ 203
Inside rear view mirror..............................149
Intuitive parking assist.............................. 255
LTA (Lane Tracing Assist).....................227
Parking Support Brake function (rear-crossing vehicles).......................277
Parking Support Brake function (static objects).........................................................272
Radar sensor...................................... 214, 249
Rain-sensing windshield wipers......... 207 RCTA............................................................... 262
Service plug ...................................................... 69
Service reminder message ..................... 362
Shift lever Hybrid transmission..................................... 191
Shift lever light ................................................321
Side airbags ...................................................... 30
Side doors........................................................ 109
Side marker lights Light switch .................................................. 200
Replacing light bulbs ............................... 400
Side mirrors Adjustment ..................................................... 150
BSM (Blind Sport Monitor).................. 247
Folding................................................................ 151
Linked mirror functi on when reversing
........................................................................... 150
Mirror position memory ...........................142
RCTA function ..............................................261
Side turn signal lights Replacing light bulbs ............................... 400
Turn signal lever .......................................... 194
Side windows ..................................................153
Smart access system with push-button startAntenna location ......................................... 125
Entry functions ..................................... 109, 114
Starting the hybrid system ...................... 184
Smartphone holder..................................... 326
Snow tires .........................................................291
Spare tire......................................................... 432 Storage location .........................................433
Spark plug ...................................................... 464
Specifications ................................................ 460
Speedometer ................................................... 83
Steering lock Column lock release ................................. 185
Steering lock system warning message........................................................................... 185
Steering wheel Adjustment ..................................................... 148
Heated steering wheel ............................. 318