3614-5. Using the driving support systems
4
Driving
RX450h_U_OM0E013U WA R N I N G ■
When using the Lexus parking assist monitor system
The parking assist monitor is a supplemental device intended to assist the driver when
backing up. When backing up, be sure to chec k visually behind and all around the vehi-
cle before proceeding.
Observe the following precautions to avoid an accident that could result in death or
serious injuries. ●
Never depend on the parking assist monitor entirely when backing up. The image
and the position of the guide lines displaye d on the screen may differ from the actual
state.
Use caution, just as you would when backing up any vehicle. ●
Be sure to back up slowly, depressing the brake pedal to control vehicle speed. ●
If you seem likely to hit nearby vehicles, obstacles, people or mount the shoulder,
depress the brake pedal to stop the vehicle. ●
The instructions given are only guidelines.
When and how much to turn the steering wheel will vary according to traffic condi-
tions, road surface conditions, vehicle condit ion, etc. when parking. It is necessary to
be fully aware of this before using the parking assist system. ●
When parking, be sure to check that the par king space will accommodate your vehi-
cle before maneuvering into it. ●
Do not use the parking assist monitor in the following cases:
• On icy or slick road surfaces, or in snow
• When using tire chains or emergency tires
• When the back door is not closed completely
• On roads that are not flat or straight, such as curves or slopes. ●
In low temperatures, the screen may darken or the image may become faint. The
image could distort when the vehicle is moving, or you may become unable to see the
image on the screen. Be sure to check dire ct visually and with the mirrors all around
the vehicle before proceeding. ●
If the tire sizes are changed, the position of the guide lines displayed on the screen
may change. ●
The camera uses a special lens. The dist ances between objects and pedestrians that
appear in the image displayed on the screen will differ from the actual distances.
( P. 3 5 5 ) ●
Estimated course line display mode: If the st eering wheel is straight and the vehicle
width guide lines and the estimated course li nes are not in alignment, have the vehicle
inspected by your Lexus dealer.
370 4-5. Using the driving support systems
RX450h_U_OM0E013U ■
Conditions under which the BSM func tion may not function correctly●
The BSM function may not detect vehicles correctly in the following situations:
• When the sensor is misaligned due to a strong impact to the sensor or its surround-
ing area
• When mud, snow, ice, a sticker, etc. is covering the sensor or surrounding area on
the rear bumper
• When driving on a road surface that is wet with standing water during bad weather,
such as heavy rain, snow, or fog
• When multiple vehicles are approaching wi th only a small gap between each vehicle
• When the distance between your vehicle and a following vehicle is short
• When there is a significant difference in speed between your vehicle and the vehicle
that enters the detection area
• When the difference in speed between your vehicle and another vehicle is changing
• When a vehicle enters a detection area traveling at about the same speed as your
vehicle
• As your vehicle starts from a stop, a vehicle remains in the detection area
• When driving up and down consecutive steep in clines, such as hills, dips in the road,
etc.
• When driving on roads with sharp bends, consecutive curves, or uneven surfaces
• When vehicle lanes are wide, or when drivin g on the edge of a lane, and the vehicle
in an adjacent lane is far away from your vehicle
• When towing a trailer (veh icles with towing package)
• When items such as a bicycle carrier ar e installed on the rear of the vehicle
• When there is a significant difference in height between your vehicle and the vehicle
that enters the detection area
• Immediately after the BSM function is turned on ●
Instances of the BSM function unnecessarily detecting a vehicle and/or object may
increase in the following situations:
• When the sensor is misaligned due to a strong impact to the sensor or its surround-
ing area
• When the distance between your vehicle and a guardrail, wall, etc. that enters the
detection area is short
• When driving up and down consecutive steep in clines, such as hills, dips in the road,
etc.
• When vehicle lanes are narrow, or when driving on the edge of a lane, and a vehicle
traveling in a lane other than the ad jacent lanes enters the detection area
• When driving on roads with sharp bends, consecutive curves, or uneven surfaces
• When the tires are slipping or spinning
• When the distance between your vehicle and a following vehicle is short
• When a bicycle carrier or other accessory is installed to the rear of the vehicle
• When towing a trailer (veh icles with towing package)
3854-5. Using the driving support systems
4
Driving
RX450h_U_OM0E013U ■
Reactivation of the TRAC system linked to vehicle speed
When only the TRAC system is turned off, the TRAC system will turn on when vehicle
speed increases. However, when TRAC, VS C and Trailer Sway Control systems are
turned off, the systems will not turn on even when vehicle speed increases.■
Reduced effectiveness of the EPS system
The effectiveness of the EPS system is reduced to prevent the system from overheating
when there is frequent steering input over an extended period of time. The steering
wheel may feel heavy as a result. Should this occur, refrain from excessive steering input
or stop the vehicle and turn the hybrid system off. The EPS system should return to nor-
mal within 10 minutes. ■
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 moved to P or N. ●
The accelerator pedal is depressed. ●
The parking brake is engaged. ●
Approximately 2 seconds elapse after the brake pedal is released.
WA R N I N G ■
The ABS does not operate effectively when ●
The limits of tire gripping performance have been exceeded (such as excessively
worn tires on a snow covered road). ●
The vehicle hydroplanes while driving at high speed on wet or slick roads. ■
Stopping distance when the ABS is operat ing may exceed that of normal conditions
The ABS is not designed to shorten the vehicle’s stopping distance. Always maintain a
safe distance from the vehicle in front of you, especially in the following situations:●
When driving on dirt, gravel or snow-covered roads ●
When driving with tire chains ●
When driving over bumps in the road ●
When driving over roads with potholes or uneven surfaces ■
TRAC may not operate effectively when
Directional control and power may not be achievable while drivin g on slippery road
surfaces, even if the TRAC system is operating.
Drive the vehicle carefully in conditions where stability and power may be lost.
386 4-5. Using the driving support systems
RX450h_U_OM0E013U WA R N I N G ■
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 extended period of time. Do not attempt 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 ap propriate to the road conditions. As these
are the systems to help ensure vehicle st ability 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 tires are inflated to the recommended tire infla-
tion pressure level.
The ABS, TRAC, VSC and Trailer Sway Control 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 caus e 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 Co ntrol 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 caus e death or serious injury.●
Firmly grip the steering wh eel. Steer straight ahead.
Do not try to control trailer swaying by turning the steering wheel. ●
Begin releasing the accelerator pedal i mmediately 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. 2 2 7 )
388 4-6. Driving tips
RX450h_U_OM0E013U ◆ Delays
Repeated acceleration and deceleration, as well as long waits at traffic lights,
will lead to bad fuel economy. Check traffic reports before leaving and avoid
delays as much as possible. When drivin g in a traffic jam, gently release the
brake pedal to allow the vehicle to move forward slightly while avoiding over-
use of the accelerator pedal. Doing so can help control excessive gasoline
consumption.
◆ Highway driving
Control and maintain the vehicle at a co nstant speed. Before stopping at a toll
booth or similar, allow plenty of time to release the accelerator and gently
apply the brakes. A greater amount of electrical energy can be regenerated
when slowing down.
◆ Air conditioning
Use the air conditioning only when necessary. Doing so can help reduce
excessive gasoline consumption.
In summer: When the ambient temperature is high, use the recirculated air
mode. Doing so will help to reduce th e burden on the air conditioning system
and reduce fuel consumption as well.
In winter: Because the gasoline engine will not automatically cut out until it
and the interior of the vehicle are warm, it will consume fuel. Also, fuel con-
sumption can be improved by avoiding overuse of the heater.
◆ Checking tire inflation pressure
Make sure to check the tire inflation pressure frequently. Improper tire infla-
tion pressure can cause poor fuel economy.
Also, as snow tires can cause large amou nts of friction, their use on dry roads
can lead to poor fuel economy. Use ti res that are appropriate for the season.
390 4-6. Driving tips
RX450h_U_OM0E013U ●
Use fluids that are appropriate to the prevailing outside temperatures.
•Engine oil
• Engine/power control unit coolant
• Washer fluid ●
Have a service technician inspect the condition of the 12-volt battery. ●
Have the vehicle fitted with four snow tires or purchase a set of tire chains for
the front tires. Ensure that all tires are of the specified size and the same brand, and that chains
match the size of the tires.
Perform the following according to the driving conditions: ●
Do not try to forcibly open a window or move a wiper that is frozen. Pour
warm water over the frozen area to melt the ice. Wipe away the water imme-
diately to prevent it from freezing. ●
To ensure proper operation of the climate control system fan, remove any
snow that has accumulated on the air inlet vents in front of the windshield. ●
Check for and remove any excess ice or snow that may have accumulated on
the exterior lights, vehicle’s roof, chassis, around the tires or on the brakes. ●
Remove any snow or mud from the bottom of your shoes before getting in the
vehicle.Winter driving tips Carry out the necessary preparations and inspections before driving the vehi-
cle in winter. Always drive the vehicle in a manner appropriate to the prevail-
ing weather conditions.
Pre-winter preparations
Before driving the vehicle
392 4-6. Driving tips
RX450h_U_OM0E013U To enable the windshield wipers to be lifted when heavy snow or icy conditions
are expected, change the rest position of the windshield wipers from the
retracted position below the hood to the service position using the wiper lever.
(
P. 2 6 3 ) ■
Tire chain installation
Observe the following precautions wh en installing and removing chains:●
Install and remove tire chains in a safe location. ●
Install tire chains on the front tires only. Do not install tire chains on the rear tires. ●
Install tire chains on front tires as tightl y as possible. Retighten chains after driving
1/4 -1/2 mile (0.5 - 1.0 km). ●
Install tire chains following the instru ctions provided with the tire chains. Windshield wipers
WA R N I N G ■
Driving with snow tires
Observe the following precautions to reduce the risk of accidents.
Failure to do so may result in a loss of ve hicle control and cause death or serious injury.●
Use tires of the specified size. ●
Maintain the recommended level of air pressure. ●
Do not drive in excess of 75 mph (120 km/h), regardless of the type of snow tires
being used. ●
Use snow tires on all, not just some wheels.■
Driving with tire chains
Observe the following precautions to reduce the risk of accidents.
Failure to do so may result in the vehicle being unable to be driven safely, and may
cause death or serious injury. ●
Do not drive in excess of the speed limit specified for the tire chains being used, or
30 mph (50 km/h), whichever is lower. ●
Avoid driving on bumpy road surfaces or over potholes. ●
Avoid sudden acceleration, ab rupt steering, sudden bra king and shifting operations
that cause sudden engine braking. ●
Slow down sufficiently before entering a cu rve to ensure that vehicle control is main-
tained. ●
Do not use the LKA (Lane-Keeping Assist) system. (if equipped) ●
Do not use the LDA (Lane Departure Alert with steering control) system. (if
equipped)
3934-6. Driving tips
4
Driving
RX450h_U_OM0E013U NOTICE ■
Repairing or replacing snow tires
Request repairs or replacement of snow tires from Lexus dealers or legitimate tire
retailers.
This is because the removal and attachment of snow tires affects the operation of the
tire pressure warning valves and transmitters. ■
Fitting tire chains
The tire pressure warning valves and transmitters may not function correctly when tire
chains are fitted.