
3864-5. Using the driving support systems
RX450h_U_OM0E013U
WARNING
■Hill-start assist control does not operate effectively when
●Do not overly rely on the hill-start assist control. The hill-start assist control may not
operate effectively on steep inclines and roads covered with ice.
●Unlike the parking brake, hill-start assist control is not intended to hold the vehicle
stationary for an exte nded period of time. Do not atte mpt to use hill-start assist con-
trol to hold the vehicle on an incline, as doing so may lead to an accident.
■When the VSC/Trailer Sway Control is activated
The slip indicator light flashes. Always drive carefully. Reckless driving may cause an
accident. Exercise particular care when the indicator light flashes.
■When the TRAC/VSC/Trailer Sway Control systems are turned off
Be especially careful and drive at a speed appropriate to the road conditions. As these
are the systems to help ensure vehicle stability and driving force, do not turn the
TRAC/VSC/Trailer Sway Control systems off unless necessary.
■Replacing tires
Make sure that all tires are of the specified size, brand, tread pattern and total load
capacity. In addition, make sure that the tire s are inflated to the recommended tire infla-
tion pressure level.
The ABS, TRAC, VSC and Trailer Sway Contro l systems will not function correctly if
different tires are installed on the vehicle.
Contact your Lexus dealer for further information when replacing tires or wheels.
■Handling of tires and the suspension
Using tires with any kind of problem or modi fying the suspension will affect the driving
assist systems, and may cause a system to malfunction.
■Trailer Sway Control precaution
The Trailer Sway Control system is not able to reduce trailer sway in all situations.
Depending on many factors such as the condit ions of the vehicle, trailer, road surface,
and driving environment, the Trailer Sway Control system may not be effective. Refer to
your trailer owner’s manual for information on how to tow your trailer properly.
■If trailer sway occurs
Observe the following precautions.
Failing to do so may cause death or serious injury.
●Firmly grip the steering wh eel. Steer straight ahead.
Do not try to control trailer sway ing by turning the steering wheel.
●Begin releasing the accelerator pedal immediately but very gradually to reduce
speed.
Do not increase speed. Do not apply vehicle brakes.
If you make no extreme correction with the steering or brakes, your vehicle and trailer
should stabilize. ( P. 227)

5377-2. Steps to take in an emergency
7
When trouble arises
RX450h_U_OM0E013U
(U.S.A.)
(Canada)
ABS warning light Indicates a malfunction in:
• The ABS; or
• The brake assist system
Have the vehicle inspected by your Lexus dealer immediately.
(Flashes)
(U.S.A.)
(Flashes)
(Canada)
Parking brake indicator
It is possible that the parking br ake is not fully engaged or released
Operate the parking brake switch once again.
This light comes on when the parking brake is not released. If the
light turns off after the parking brak e is fully released, the system is
operating normally.
(Flashes)
Brake hold operated indicator Indicates a malfunction in the brake hold system
Have the vehicle inspected by your Lexus dealer immediately.
Electric power steering system warning light (warning buzzer)
Indicates a malfunction in the EPS (Electric Power Steering) sys-
tem
Have the vehicle inspected by your Lexus dealer immediately.
LKA indicator/LDA indicator
Indicates a malfunction in the LKA (Lane-Keeping Assist)/LDA
(Lane Departure Alert with steering control)
When “Lane Keeping Assist Unav ailable” or “Lane Departure
Alert Unavailable” is displayed on the multi-information display,
turn the LKA/LDA system off, drive the vehicle for a short time,
and then turn the LKA/LDA system back on. ( P. 296, 305)
When a message other than above is displayed, follow the
instructions displayed in the message.
Slip indicator
When the warning lig ht is illuminated:
Indicates a malfunction in:
• The VSC system;
• The TRAC system;
• The Trailer Sway Control; or
• The hill-start assist control system
Have the vehicle inspected by your Lexus dealer immediately.
When the warning light flashes:
Indicates that the ABS, VSC, TR AC or Trailer Sway Control sys-
tem is operating
Warning lightWarning light/Details/Actions

5387-2. Steps to take in an emergency
RX450h_U_OM0E013U
(If equipped)
PCS warning lightWhen the warning light flashes (and a buzzer sounds):
Indicates a malfunction in the PCS (Pre-Collision System)
Have the vehicle inspected by your Lexus dealer immediately.
When the warning light flashes (and a buzzer does not sound):
Indicates that the PCS (Pre-Collision System) is temporarily
unavailable, possibly due to either of the following:
• An area around the radar sensor or camera sensor being dirty,
fogged up or covered with condensation, ice, stickers, etc.
Clear the dirt, fog, condensation, ice, stickers, etc.
( P. 274, 275)
• Radar sensor or camera sensor temperature being outside of its
operational range
Wait for a while until the area around the front sensor has cooled
down sufficiently.
When the warning lig ht is illuminated:
Either the VSC (Vehicle Stability Control) system or PCS (Pre-
Collision System) is disabled or both are disabled.
To enable the PCS, enable bo th the VSC system and PCS.
( P. 283, 384)
Low fuel level warning light
Indicates that remaining fuel is approximately 2.9 gal. (11.0 L,
2.4 Imp. gal.) or less
Refuel the vehicle.
Seat belt reminder light (warning buzzer)*
Warns the driver and/or front passenger to fasten their seat belts
Fasten the seat belt.
If the front passenger’s seat is occupied, the front passenger’s
seat belt also needs to be fastened to make the warning light
(warning buzzer) turn off.
Tire pressure warning light
Indicates the following:
• Low tire pressure due to flat tire;
• Low tire pressure due to natural causes; or
• The tire pressure warnin g system is malfunctioning
Immediately stop the vehicle in a safe place.
Handling method ( P. 540)
Master warning light
A buzzer sounds and the warning light comes on and flashes to
indicate that the master warnin g system has detected a malfunc-
tion.
P. 543
Warning lightWarning light/Details/Actions

5597-2. Steps to take in an emergency
7
When trouble arises
RX450h_U_OM0E013U
WARNING
■When using the compact spare tire
●Remember that the compact spare tire provided is specifically 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 braking 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:
Also, not only can the following system not be utilized fully, but it may even negatively
affect the drive-train components:
• E-Four (AWD models)
■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 death 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 brak-
ing.
• ABS & Brake assist
• VSC
• TRAC
• EPS
• Trailer Sway Control
• VDIM
• Adaptive Variable Suspension System (if equipped)
• Cruise control (if equipped)
• Dynamic radar cruise control (if equipped)
• Dynamic radar cruise control with full- speed range (if equipped)
• PCS (Pre-Collision System) (if equipped)
• LDA (Lane Departure Alert with
steering control) (if equippedF
• LKA (Lane-Keeping Assist) (if
equipped)
• Automatic High Beam (if equipped)
• AFS (Adaptive Front-lighting System) (if equipped)
• Tire pressure warning system
• Intuitive parking assist
• Lexus parking assist monitor (if equipped)
• Panoramic view monitor (if equipped)
• BSM (Blind Spot Monitor)
• Navigation system

645Alphabetical index
RX450h_U_OM0E013U
EngineACCESSORY mode...................... 233
Compartment......................................475
Engine switch ....................................... 232
Hood ........................................................ 473
How to start the hybrid system .................................................. 232
Identification number ...................... 583
If your vehicle has to be stopped in an emergency ..........529
Ignition switch (power switch) .... 232
Overheating .........................................574
Power switch........................................ 232
Engine coolant Capacity ................................................ 587
Checking................................................ 479
Preparing and checking before winter ................................... 390
Engine coolant temperature gauge .........................................................97
Engine oil Capacity ................................................ 585
Checking................................................ 476
Preparing and checking before winter ................................... 390
Engine oil maintenance data ........... 478
Engine switch ......................................... 232
Enhanced VSC ...................................... 381
EPS (Electronic Power Steering) ......... 381 Warning light .......................................537
EV drive mode....................................... 237
EV indicator ............................................... 78
Event data recorder (EDR) .................... 11 Flat tire ...................................................... 549
Floor mats................................................... 28
Fluid
Brake....................................................... 588
Transmission ....................................... 588
Washer ................................................... 482
Fog lights Replacing light bulbs .........................513
Switch ...................................................... 259
Front passenger footwell hooks.......................................................442
Front passenger occupant classification system ............................. 51
Front passenger’s seat belt reminder light ..................................... 538
Front seat heaters .................................. 415
Front seats ................................................. 164 Adjustment..............................................164
Cleaning................................................. 462
Correct driving posture .................... 30
Driving position memory................. 174
Head restraints ..................................... 179
Power easy access system ............. 174
Seat heaters ............................................415
Seat position memory ....................... 174
Front side marker lights Light switch............................................. 251
Replacing light bulbs .........................513
Wattage ................................................ 590F

655Alphabetical index
RX450h_U_OM0E013U
Sun visors ................................................. 432
SunshadePanoramic moon roof .......................197
Rear door...............................................443
Roof............................................................ 194
Switches Automatic High Beam switch .... 255
Brake hold switch ..............................249
Cruise control switch............................... 311, 323, 335
Door lock switch ................................. 138
Driving mode select switch .......... 377
Driving position memory switches .................................................174
Electronic sunshade switch ............197
Emergency flashers switch .......... 528
EV drive mode switch ..................... 237
Fog light switch ...................................259
Garage door opener switches ...............................................445
Heated steering wheel switch..................................................... 415
HUD (Head-up display) switches .................................................. 118
Ignition switch ...................................... 232
LDA (Lane Departure Alert) switch................................................... 305
Light switch ............................................ 251
LKA (Lane-Keeping Assist) switch....................................................296
Meter control switches .................... 104
Moon roof switches........................... 193
“ODO/TRIP” switch ......................... 105
Outside rear view mirror switches ................................................ 185 Paddle shift switches.............. 240, 241
Panoramic moon roof
switches ................................................ 197
Parking brake switch ....................... 245
Power back door opener and closer switch .................. 143, 145
Power switch ....................................... 232
Power window switch ...................... 189
Rear window and outside rear view mirror
defoggers switch............................409
Rear window wiper and washer switch .................................. 265
Seat heater switches ............... 415, 416
Seat ventilator switches ....................416
“SOS” button ....................................... 452
Vehicle-to-vehicle distance button........................311, 323
VSC OFF switch ...............................383
Window lock switch ......................... 189
Windshield wipers and washer switch .................................. 260

657Alphabetical index
RX450h_U_OM0E013U
TransmissionDriving mode select switch .......... 377
Hybrid transmission..........................239
If the shift lever cannot be shifted from P .................................. 563
Paddle shift switches ............. 240, 241
S mode ......................................................241
Trip meters ................................................. 115
Turn signal lights Replacing light bulbs ......................... 513
Turn signal lever ................................. 244
Wattage ................................................. 590
Vanity lights............................................. 432 Wattage ................................................. 590
Vanity mirrors ........................................ 432 Vanity lights .......................................... 432 VDIM (Vehicle Dynamics
Integrated Management).............. 382
Vehicle data recordings......................... 10
Vehicle Dynamics Integrated Management (VDIM)..................... 382
Vehicle identification number ........ 583
Vehicle proximity notification system ........................................................ 77
Vehicle Stability Control (VSC) ......381
VSC (Vehicle Stability Control) ......381
Warning buzzers Approach warning ................ 318, 330
Downshifting ........................................ 242
Intuitive parking assist...................... 343
Lane departure alert function.................................... 293, 302
Light reminder .................................... 253
Open door .............................................140
Pre-collision warning.......................280
Seat belt reminder.............................538
Vehicle sway warning .........294, 303
V
W