warning light LEXUS RX450H 2019 Workshop Manual

3054-5. Using the driving support systems
4
Driving
RX450h_RX450hL_U
■Conditions in which functions may not operate properly
In the following situations, the camera sensor may not detect white (yellow) lines and var-
ious functions may not operate normally.
●There are shadows on the road that run parallel with, or cover, the white (yellow) lines.
●The vehicle is driven in an ar ea without white (yellow) lines, such as in front of a tollgate
or checkpoint, or at an intersection, etc.
●The white (yellow) lines are cracked, “Botts ’ dots”, “Raised pavement marker” or stones
are present.
●The white (yellow) lines cannot be seen or are difficult to see due to sand, etc.
●The vehicle is driven on a road surface that is wet due to rain, puddles, etc.
●The traffic lines are yellow (which may be more difficult to recognize than lines that are
white).
●The white (yellow) lines cross over a curb, etc.
●The vehicle is driven on a bright surface, such as concrete.
●The vehicle is driven on a surface that is bright due to reflected light, etc.
●The vehicle is driven in an area where the brightness changes suddenly, such as at the
entrances and exits of tunnels, etc.
●Light from the headlights of an oncoming vehicle, the sun, etc., enters the camera.
●The vehicle is driven where the road diverges, merges, etc.
●The vehicle is driven on a slope.
●The vehicle is driven on a road which tilts left or right, or a winding road.
●The vehicle is driven on an unpaved or rough road.
●The vehicle is driven around a sharp curve.
●The traffic lane is excessively narrow or wide.
●The vehicle is extremely tilted due to carry ing heavy luggage or having improper tire
pressure.
●The distance to the preceding vehicle is extremely short.
●The vehicle is moving up and down a large am ount due to road conditions during driv-
ing (poor roads or road seams).
●The headlight lenses are dirty and emit a faint amount of light at night, or the beam axis
has deviated.
●The vehicle is struck by a crosswind.
●The vehicle has just changed lane s or crossed an intersection.
●Snow tires, etc., are equipped.
■If the LKA indicator is illuminated in ambe r and a warning message is displayed on the
multi-information display
 P. 660
■Customization
Some functions can be customized. ( P. 108)

3094-5. Using the driving support systems
4
Driving
RX450h_RX450hL_U
This mode employs a radar sensor to detect the presence of vehicles up to
approximately 328 ft. (100 m) ahead, determines the current vehicle-to-vehicle
following distance, and operates to main tain a suitable following distance from
the vehicle ahead.
Note that vehicle-to-vehicle distance will cl ose in when traveling on downhill slopes.
Example of constant speed cruising
When there are no vehicles ahead
The vehicle travels at the speed set by the driver. The desired vehicle-to-vehicle dis-
tance can also be set by operating the vehicle-to-vehicle distance switch.
Example of deceleration cruising and follow-up cruising
When a preceding vehicle driving slower than the set speed appears
When a vehicle is detected running ahead of you, the system automatically deceler-
ates your vehicle. When a greater reduction in vehicle speed is necessary, the system
applies the brakes (the stop lights will come on at this time). The system will respond to
changes in the speed of the vehicle ahead in order to maintain the vehicle-to-vehicle
distance set by the driver. Approach warning warns you when the system cannot
decelerate sufficie ntly to prevent your vehicle from closing in on the vehicle ahead.
When the vehicle ahead of you stops, your vehicle will also stop (vehicle is stopped by
system control). After the vehicle ahead starts off, pushing the cruise control lever up
or depressing the accelerator pedal will resume follow-up cruising.
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 reached. The system then returns to con-
stant speed cruising.
Driving in vehicle-to-vehicle distance control mode
1
2
3

3214-5. Using the driving support systems
4
Driving
RX450h_RX450hL_U
Press “” or “ ” of the meter control switches, select .
Press “ ” or “ ” of the meter control switches, select “BSM”.
Press “ ” or “ ” of the meter control switch es, select “BSM” or “RCTA”.
■Outside rear view mirror indicator visibility
In strong sunlight, the outside rear view mirror indicator may be difficult to see.
■Hearing the RCTA buzzer
The RCTA buzzer may be difficult to hear over loud noises, such as if the audio system
volume is high.
■When there is a malfunction in the Blind Spot Monitor
If a system malfunction is detected due to any of the following, a warning message will be
displayed: ( P. 667)
●A sensor is malfunctioning
●A sensor is dirty or covere d with snow or a sticker
●The outside temperature is extremely high or low
●Sensor voltage is abnormal
●A sensor is misaligned
■Certification for the Blind Spot Monitor
For vehicles sold in the U.S.A.
For vehicles sold in Canada
Turning the BSM function/RCTA function on/off
1
2
3

3224-5. Using the driving support systems
RX450h_RX450hL_U
■Customization
Some functions can be customized. ( P. 331, 667)
WARNING
■Handling the radar sensor
Blind Spot Monitor sensors ar e installed behind the left and right sides of the rear
bumper respectively. Observe the following to ensure the Blind Spot Monitor can
function correctly.
●Do not subject a sensor or its surrounding area on the rear bumper to a strong
impact.
If a sensor is moved even slightly off po sition, the system may malfunction and vehi-
cles may not be detected correctly.
In the following situations , have your vehicle inspected by your Lexus dealer.
• A sensor or its surrounding area is subject to a strong impact.
• If the surrounding area of a sensor is sc ratched or dented, or part of them has
become disconnected.
●Do not disassemble the sensor.
●Do not attach stickers to the sensor or surrounding area on the rear bumper.
●Do not modify the sensor or surrounding area on the rear bumper.
●Do not paint the rear bumper any colo r other than an official Lexus color.
●Keep the sensors and the surrounding areas
on the rear bumper clean at all times.
If a sensor or its surrounding area on the rear
bumper is dirty or covered with snow, the
Blind Spot Monitor may not operate and a
warning message (P. 667) will be dis-
played. In this situation, clear off the dirt or
snow and drive the vehicle with the operation
conditions of the BSM function ( P. 325)
satisfied for approximately 10 minutes. If the
warning message does not disappear, have
the vehicle inspected by your Lexus dealer.

3854-5. Using the driving support systems
4
Driving
RX450h_RX450hL_U
■Turning off both TRAC VSC and Trailer Sway Control systems
To turn the TRAC VSC and Trailer Sway Co ntrol systems off, press and hold for
more than 3 seconds whil e the vehicle is stopped.
The VSC OFF indicator light will come on an d the “Traction Control Turned Off” will be
shown on the multi-information display.
*
Press again to turn the systems back on.
*: On vehicles with PCS (Pre-Collision Sy stem), pre-collision brake assist and pre-
collision braking will also be disabled. The PCS warning light will come on and a
message will be displa yed on the multi-information display. (P. 296)
■When the message is displayed on the mu lti-information display showing that TRAC
has been disabled even if has not been pressed
TRAC cannot be operated. Contact your Lexus dealer.
■Operating conditions of hill-start assist control
When the following four conditions are met, the hill-start assist control will operate:
●The shift lever is in a position other than P or N (when starting off forward/backward on
an upward incline).
●The vehicle is stopped
●The accelerator pedal is not depressed
●The parking brake is not engaged
■Automatic system cancelation of hill-start assist control
The hill-start assist control will turn off in any of the following situations:
●The shift lever is shifted to P or N
●The accelerator pedal is depressed
●The parking brake is engaged
●2 seconds at maximum elapsed after the brake pedal is released
■Sounds and vibrations caused by the ABS, brake assist, VSC, Trailer Sway Control,
TRAC and hill-start assist control systems
●A sound may be heard from the engine compartment when the brake pedal is
depressed repeatedly, when the hybrid system is started or just after the vehicle begins
to move. This sound does not indicate that a malfunction has occurred in any of these
systems.
●Any of the following conditions may occur when the above systems are operating.
None of these indicates that a malfunction has occurred.
• Vibrations may be felt through the vehicle body and steering.
• A motor sound may be heard also after the vehicle comes to a stop.

3874-5. Using the driving support systems
4
Driving
RX450h_RX450hL_U
WARNING
■Hill-start assist control does not operate effectively when
●Do not overly rely on hill-start assist control. 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 TRAC/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 stab ility and driving force, do not turn the
TRAC/VSC/Trailer Sway Contro l systems off unless necessary.
Trailer Sway Control is part of the VSC syst em and will not operate if VSC is turned off
or experiences a malfunction.
■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, Trailer Sway Control and VS C systems will not function correctly if
different tires are installed on the vehicle.
Contact your Lexus dealer for further in formation 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 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. 234)

4055-1. Basic Operations
5
Lexus Display Audio system
RX450h_RX450hL_U
■When using the screen
●Under extremely cold conditions, the Lexus Display Audio controller may react slowly.
●If the screen is cold, the display may be dark, or the system may seem to be operating
slightly slower than normal.
●The screen may seem dark and hard to see when viewed through sunglasses. Change
your angle of viewing, adjust the display on the “Display” screen (P. 417) or remove
your sunglasses.
■Using cellular phones
Interference may be heard through the audi o system’s speakers if a cellular phone is
being used inside or close to the vehicle while the audio system is operating.
WARNING
■Using the Lexus Display Audio controller
Be careful when touching the Lexus Display Audio controller in extreme temperatures
as it may become very hot or cold due to the temperature inside the vehicle.
■Laser product
●CAUTION
USE OF CONTROL OR ADJUSTMENT OR PERFORMANCE OF PROCE-
DURES OTHER THAN THOSE SPECIFIED HEREIN MAY RESULT IN HAZARD-
OUS RADIATION EXPOSURE.
●CAUTION
THE USE OF OPTICAL INSTRUMENTS WITH THIS PRODUCT WILL
INCREASE EYE HAZARD.
NOTICE
■To prevent Lexus Display Au dio controller malfunction
●Do not allow the Lexus Display Audio controll er to come into contact with food, liq-
uid, stickers or lit cigarettes as doing so may cause it to change color, emit a strange
odor or stop functioning.
●Do not subject the Lexus Display Audio controller to excessive pressure or strong
impact as the controller may bend or break off.
■To prevent battery discharge
Do not leave the audio system on longer than necessary when the engine is off.
■To avoid damaging the audio system
Take care not to spill drinks or other fluids on the audio system.

5336-4. Using the storage features
6
Interior features
RX450h_RX450hL_U
RX450hL
Glove box (P. 534)
Auxiliary boxes (if equipped)
( P. 539)
Door pockets ( P. 537)
Bottle holders ( P. 537) Console box (
P. 534)
Cup holders ( P. 535)
Coin box ( P. 538)
WARNING
●Do not leave glasses, lighters or spray cans in the storage spaces, as this may cause
the following when cabin temperature becomes high:
• Glasses may be deformed by heat or cracke d if they come into contact with other
stored items.
• Lighters or spray cans may explode. If they come into contact with other stored
items, the lighter may catch fire or the spray can may release gas, causing a fire
hazard.
●When driving or when the storage compartments are not in use, keep the lids closed.
In the event of sudden braking or sudden swerving, an accident may occur due to an
occupant being struck by an open lid or the items stored inside.
1
2
3
4
5
6
7

5576-5. Using the other interior features
6
Interior features
RX450h_RX450hL_U
Use the front passenger footwell hooks
to help support and prevent objects
placed on the floor, such as a grocery
bag, from overturning.
Pull the sunshade up using the tab and
hook the sunshade on to the anchors.
To lower the sunshade, pull it up slightly
using the tab, unhook it from the
anchors, and lower it slowly.
Front passenger footwell hooks
NOTICE
To prevent the hooks from being damaged, do not hang anything from a hook or apply
excessive force to it.
Rear door sunshades (if equipped)
WARNING
When a rear door sunshade is in use, do not put fingers, etc. on the anchors or in the
groove of the rear door sunshade. Otherwise, a finger, etc. may get caught, possibly
causing an injury.
NOTICE
●Do not put anything in an area where it may interfere with the operation of a rear
door sunshade.
●To prevent damage to the rear door sunshades, do not apply excessive load or attach
items to the rear door sunshades.

5947-3. Do-it-yourself maintenance
RX450h_RX450hL_U
*: Vehicles with sing le-beam headlights
Washer fluid
( P. 604)• Water or washer fluid containing antifreeze (for winter use)
• Funnel (used only for adding water or washer fluid)
WARNING
The engine compartment contains many mechan isms and fluids that may move suddenly,
become hot, or become electrically energize d. To avoid death or serious injury, observe
the following precautions.
■When working on the engine compartment
●Make sure that the “ACCESSORY” or “I GNITION ON” on the multi-information
display and the “READY” indicator are both off.
●Keep hands, clothing and tools away from the moving fan and engine drive belt.
●Be careful not to touch the engine, power co ntrol unit, radiator, exhaust manifold, etc.
right after driving as they may be hot. Oil and other fluids may also be hot.
●Do not leave anything that may burn easily, such as paper and rags, in the engine
compartment.
●Do not smoke, cause sparks or expose an open flame to fuel. Fuel fumes are flamma-
ble.
■When working near the electric cooling fans or radiator grille
Be sure the power switch is off.
With the power switch in ON mode, the electric cooling fans may automatically start to
run if the air conditioning is on and/ or the coolant temperature is high. ( P. 602)
■Safety glasses
Wear safety glasses to prevent flying or falling material, fluid spray, etc. from getting in
your eyes.
NOTICE
■If you remove the air cleaner filter
Driving with the air cleaner f ilter removed may cause excessive engine wear due to dirt
in the air.
ItemsParts and tools