2021 LEXUS RX450h warning

1974-2. Driving procedures
4
Driving
■If “Parking Brake Overheated Parking
Brake Unavailable” is displayed on the
multi-information display
If the parking brake is operated repeatedly
over a short period of time, the system may
restrict operation to prevent overheating. If
this happens, refrain from operating the
parking brake. Normal operation will return
after about 1 minute.
■If “EPB Activation Stopped Incom-
pletely” or “Parking Brake Unavailable”
is displayed on th e multi-information
display
Operate the parking brake switch. If the
message does not disappear after operat-
ing the switch several times, the system may
be malfunctioning. Have the vehicle
inspected by your Lexus dealer immedi-
ately.
■Parking brake operation sound
When the parking brake operates, a motor
sound (whirring sound) may be heard. This
does not indicate a malfunction.
■Parking brake indicator light and park-
ing brake light
●Depending on the power switch mode,
the parking brake in dicator light and
parking brake light will turn on and stay
on as described below:
ON mode: Comes on until the parking
brake is released.
Not in ON mode: Stays on for approxi-
mately 15 seconds.
●When the power switch is turned off with
the parking brake set, the parking brake
indicator light and parking brake light will
stay on for about 15 seconds. This does
not indicate a malfunction.
■Changing the mode
When changing the automatic mode on/off,
the message will be shown on the
multi-information display and the buzzer
sounds.
■Parking the vehicle
 P.164
■Parking brake engaged warning buzzer
A buzzer will sound if the vehicle is driven
with the parking brake engaged. “Release Parking Brake” is displayed on the
multi-information display.
■Warning messages and buzzers
Warning messages and buzzers are used to
indicate a system malfunction or to inform
the driver of the need for caution. If a warn-
ing message is shown on the multi-informa-
tion display, read the message and follow
the instructions.
■If the brake system warning light comes
on
 P.418
■Usage in winter time
 P.293
WARNING
■When parking the vehicle
Do not leave a child in the vehicle alone.
The parking brake may be released unin-
tentionally and there is the danger of the
vehicle moving that may lead to an acci-
dent resulting in death or serious injury.
■Parking brake switch
Do not set any objects near the parking
brake switch. Objects may interfere with
the switch and may lead the parking
brake to unexpectedly operate.
NOTICE
■When parking the vehicle
Before you leave the vehicle, shift the
shift lever to P, set the parking brake and
make sure that the vehicle does not
move.
■When the system malfunctions
Stop the vehicle in a safe place and
check the warning messages.

1984-2. Driving procedures
Turns the brake hold system on
The brake hold standby indicator (green) comes on. While the system is holding
the brake, the brake hold operated indica-
tor (yellow) comes on.
■Brake hold system operating conditions
The brake hold system cannot be turned on
in the following conditions:
●The driver’s door is not closed.
●The driver is not wearing the seat belt.
If any of the conditions above are detected
when the brake hold system is enabled, the
system will turn off and the brake hold
standby indicator light will go off. In addi-
tion, if any of the conditions are detected
while the system is holding the brake, a
warning buzzer will sound and a message
will be shown on the multi-information dis-
NOTICE
■When the parking brake cannot be
released due to a malfunction
Driving the vehicle with the parking
brake set will lead to brake components
overheating, which may affect braking
performance and increase brake wear.
Have the vehicle inspected by your
Lexus dealer immediately if this occurs.
Brake Hold
The brake hold system keeps the
brake applied when the shift lever is
in D, S or N with the system on and
the brake pedal has been
depressed to stop the vehicle. The
system releases the brake when the
accelerator pedal is depressed with
the shift lever in D or S to allow
smooth start off.
Enabling the system
A
B

1994-2. Driving procedures
4
Driving
play. The parking brake will then be set
automatically.
■Brake hold function
●If the brake pedal is left released for a
period of about 3 minutes after the sys-
tem has started holding the brake, the
parking brake will be set automatically. In
this case, a warning buzzer sounds and a
message is shown on the multi-informa-
tion display.
●To turn the system off while the system is
holding the brake, firmly depress the
brake pedal and press the button again.
●The brake hold function may not hold the
vehicle when the vehicle is on a steep
incline. In this situation, it may be neces-
sary for the driver to apply the brakes. A
warning buzzer will sound and the
multi-information display will inform the
driver of this situation. If a warning mes-
sage is shown on the multi-information
display, read the message and follow the
instructions.
■When the parking brake is set automati-
cally while the system is holding the
brakes
Perform any of the follo wing operations to
release the parking brake.
●Depress the accelerator pedal. (The
parking brake will not be released auto-
matically if the seat belt is not fastened.)
●Operate the parking brake switch with
the brake pedal depressed.
Make sure that the pa rking brake indicator
light goes off. ( P.195)
■When an inspection at your Lexus
dealer is necessary
When the brake hold standby indicator
(green) does not illuminate even when the
brake hold switch is pressed with the brake
hold system operating conditions met, the
system may be malfun ctioning. Have the
vehicle inspected at your Lexus dealer.
■If “Brake Hold Fault Depress Brake to
Deactivate Visit Your Dealer” or “Brake
Hold Malfunction Visit Your Dealer” is
displayed on the multi-information dis-
play
The system may be ma lfunctioning. Have
the vehicle inspected by your Lexus dealer.
■Warning messages and buzzers
Warning messages and buzzers are used to
indicate a system malfunction or to inform
the driver of the need for caution. If a warn-
ing message is shown on the multi-informa-
tion display, read the message and follow
the instructions.
■If the brake hold operated indicator
flashes
 P.425
WARNING
■When the vehicle is on a steep incline
When using the brake hold system on a
steep incline exercise caution. The brake
hold function may not hold the vehicle in
such a situation.
■When stopped on a slippery road
The system cannot stop the vehicle when
the gripping ability of the tires has been
exceeded. Do not use the system when
stopped on a slippery road.
NOTICE
■When parking the vehicle
The brake hold system is not designed
for use when parking the vehicle for a
long period of time. Turning the power
switch off while the system is holding the
brake may release the brake, which
would cause the vehicle to move. When
operating the power switch, depress the
brake pedal, shift the shift lever to P and
set the parking brake.

2034-3. Operating the lights and wipers
4
Driving
1Press the Automatic High Beam
switch.
2 Turn the headlight switch to the
or position.
The Automatic High Beam indicator will come on when the system is operating.
■Conditions to turn the high beams on/off
automatically
●When all of the follo
wing conditions are
met, the high beams will be turned on
automatically (after approximately 1 sec-
ond):
• The vehicle speed is approximately 21 mph (34 km/h) or more.
• The area ahead of the vehicle is dark.
• There are no vehicles ahead with head- lights or tail lights turned on.
• There are few streetlights on the road ahead.
●If any of the following conditions is met,
the high beams will turn off automatically:
• The vehicle speed is below approxi-
mately 17 mph (27 km/h).
• The area ahead of the vehicle is not dark.
• Vehicles ahead have their headlights or
tail lights turned on.
• There are many streetlights on the road ahead.
■Camera sensor dete ction information
●The high beams may not be automatically
turned off in the following situations:
• When a vehicle suddenly appears from around a curve
• When the vehicle is cut in front of by
another vehicle
• When vehicles ahead cannot be detected due to repeated curves, road
dividers or roadside trees
• When vehicles ahead appear in a far- away lane on a wide road
• When the lights of vehicles ahead are not
on
●The high beams may be turned off if a
vehicle ahead that is using fog lights with-
AHB (Automatic High
Beam)
The Automatic High Beam uses a
camera sensor located behind the
upper portion of the windshield to
assess the brightness of the lights of
vehicles ahead, streetlights, etc.,
and automatically turns the high
beams on or off as necessary.
WARNING
■Limitations of the Automatic High
Beam
Do not overly rely on the Automatic High
Beam. Always drive sa fely, taking care to
observe your surroundings and turning
the high beams on or off manually if nec-
essary.
■To prevent incorrect operation of the
Automatic High Beam system
Do not overload the vehicle.
Activating the Automatic High
Beam

2084-3. Operating the lights and wipers
●If the wiper switch is turned to the
“AUTO” position while the power switch
is in ON mode, the wipers will operate
once to show that AUTO mode is acti-
vated.
●When the sensor sensitivity ring is turned
toward high while in “AUTO” position, the
wipers will operate once to indicate that
the sensor sensitiv ity is enhanced.
●If the temperature of the raindrop sensor
is 194°F (90°C) or higher, or 5°F (-15°C)
or lower, automatic operation may not
occur. In this case, operate the wipers in
any mode other than AUTO mode.
■If no windshield washer fluid sprays
Check that the washer nozzles are not
blocked, if there is washer fluid in the
washer fluid tank.
■Front door opening linked windshield
wiper stop function
When “AUTO” is selected and the wind-
shield wipers are operatin g, if a front door is
opened, the operation of the windshield
wipers will be stopped to prevent anyone
near the vehicle from being sprayed by
water from the wipers, provided the vehicle
is stopped with the parking brake applied or
the shift lever in P. When the front door is
closed, wiper operation will resume.
■Customization
Some functions can be customized.
(  P.480)
When the windshield wipers are not
being used, they retract to below the
hood. To enable the windshield wipers
to be lifted when parking in cold condi-
tions or when replacing a windshield
wiper insert, change the rest position of
the windshield wipers to the service
position using the wiper lever.
WARNING
■Caution regarding the use of wind-
shield wipers in AUTO mode
The windshield wipers may operate
unexpectedly if the sensor is touched or
the windshield is subj ect to vibration in
A U T O m o d e . T a k e c a r e t h a t y o u r f i n g e r s ,
etc. do not become caught in the wind-
shield wipers.
■Caution regarding the use of washer
fluid
When it is cold, do not use the washer
fluid until the windshield becomes warm.
The fluid may freeze on the windshield
and cause low visibility. This may lead to
an accident, resulting in death or serious
injury.
NOTICE
■When the washer fluid tank is empty
Do not operate the switch continually as
the washer fluid pump may overheat.
■When a nozzle becomes blocked
In this case, contact your Lexus dealer.
Do not try to clear it with a pin or other
object. The nozzle will be damaged.
Changing the windshield wiper
rest position/Lifting the wind-
shield wipers

2114-4. Refueling
4
Driving
4-4.Refueling
Close all the doors and windows,
and turn the power switch off.
 Confirm the type of fuel.
■Fuel types
 P.469
■Fuel tank opening for unleaded gasoline
To help prevent incorrect fueling, your vehi-
cle has a fuel tank opening that only accom-
modates the special nozzle on unleaded
fuel pumps.
Opening the fuel tank cap
The fuel tank of your vehicle has a
special structure, which requires a
reduction in fuel tank pressure
before refueling. After the opener
switch has been pressed, it will take
several seconds until the vehicle is
ready for refueling.
Before refueling the vehicle
WARNING
■When refueling the vehicle
Observe the following precautions while
refueling the vehicle. Failure to do so may
result in death or serious injury.
●After exiting the vehicle and before
opening the fuel door, touch an
unpainted metal surface to discharge
any static electricity. It is important to
discharge static electricity before refu-
eling because sparks resulting from
static electricity can cause fuel vapors
to ignite while refueling.
●Always hold the grips on the fuel tank
cap and turn it slowly to remove it.
A whooshing sound may be heard
when the fuel tank cap is loosened.
Wait until the sound cannot be heard
before fully removing the cap. In hot
weather, pressurized fuel may spray
out of the filler neck and cause injury.
●Do not allow anyone that has not dis-
charged static electricity from their
body to come close to an open fuel
tank.
●Do not inhale vaporized fuel.
Fuel contains substances that are
harmful if inhaled.
●Do not smoke while refueling the vehi-
cle.
Doing so may cause the fuel to ignite
and cause a fire.
●Do not return to the vehicle or touch
any person or object that is statically
charged.
This may cause static electricity to
build up, resulting in a possible ignition
hazard.
■When refueling
Observe the following precautions to
prevent fuel overflowing from the fuel
tank:
●Securely insert the fuel nozzle into the
fuel filler neck.
●Stop filling the tank after the fuel noz-
zle automatically clicks off.
●Do not top off the fuel tank.
NOTICE
■Refueling
●Finish refueling within 30 minutes. If
more than 30 minutes passes, the
internal valve closes. In this condition,
fuel may overflow during the refueling
process.
Press the fuel filler door opener switch
again.

2134-4. Refueling
4
Driving
WARNING
■When replacing the fuel tank cap
Do not use anything but a genuine Lexus
fuel tank cap designed for your vehicle.
Doing so may cause a fire or other inci-
dent which may result in death or serious
injury.

2144-5. Using the driving support systems
4-5.Using the driving support systems
■PCS (Pre-Collision System)
 P.220
■LTA (Lane Tracing Assist)
 P.227
■AHB (Automatic High Beam)
 P.203
■RSA (Road Sign Assist)*
P.236
*:If equipped
■Dynamic radar cruise control with
full-speed range
 P.238 Two types of sensors, located behind
the front grille and windshield, detect
information necessary to operate the
drive assist systems.
Radar sensor
Front camera
Lexus Safety System + 2.0
The Lexus Safety System + 2.0 con-
sists of the following drive assist sys-
tems and contributes to a safe and
comfortable driving experience:
Driving assist system
WARNING
■Lexus Safety System + 2.0
The Lexus Safety System + 2.0 is
designed to operate under the assump-
tion that the driver wi ll drive safely, and is
designed to help reduce the impact to
the occupants and the vehicle in the case
of a collision or assist the driver in normal
driving conditions.
As there is a limit to the degree of recog-
nition accuracy and control performance
that this system can provide, do not
overly rely on this system. The driver is
always responsible for paying attention
to the vehicle’s surro undings and driving
safely.
Sensors
WARNING
■To avoid malfunction of the radar sen-
sor
Observe the following precautions.
Otherwise, the radar sensor may not
operate properly, possibly leading to an
accident resulting in death or serious
injury.
A
B