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2-4. Using other driving systems
RX400h_U
CAUTION
■When the laser radar sensor may not be correctly detecting the vehicle ahead
Apply the brakes as necessary when any of the following types of vehicles are in
front of you.
As the sensor may not be able to correctly detect these types of vehicles, the prox-
imity alarm (→P. 164) will not be activated, and an accident may result.
●Vehicles that cut in suddenly
●Vehicles traveling at low speeds
●Vehicles that are not moving
●Vehicles with small rear ends (trailers with no load on board etc.)
●Motorcycles traveling in the same lane
■Conditions under which the vehicle-to-vehicle distance control may not function
correctly
Apply the brakes as necessary in the following conditions as the laser radar sensor
may not be able to correctly detect vehicles ahead, and an accident may result.
●When water or snow thrown up by the surrounding vehicles hinders the function-
ing of the sensor
●When your vehicle is pointing upwards (caused by a heavy load in the luggage
compartment, etc.)
●When the road curves or when the lanes are narrow
●When steering wheel operation or your position in the lane is unstable
■To ensure the laser radar sensor functions correctly
Do not do the following to the sensor as doing so may cause the sensor not to func-
tion correctly and could result in an accident.
●Stick or attach anything to them
●Leave them dirty
●Disassemble, subject them to strong shocks
●Modify or paint them
●Replace them with non-genuine parts

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2-4. Using other driving systems
2
When driving
RX400h_U
Driving assist systems
To help enhance driving safety and performance, the following systems
operate automatically in response to various driving situations. Be aware,
however, that these systems are supplementary and should not be relied
upon too heavily when operating the vehicle.
■ ABS (Anti-lock Brake System)
Helps to prevent wheel lock when the brakes are applied suddenly, or if
the brakes are applied while driving on a slippery road surface.
■Brake assist
Generates an increased level of braking force after the brake pedal is
depressed, when the system detects a panic stop situation.
■VSC (Vehicle Stability Control)
Helps the driver to control skidding when swerving suddenly or turning on
slippery road surfaces.
■Traction Control
Maintains drive power and prevents the front wheels (2WD models) or all
wheels (AWD models) from spinning wh en starting the vehicle or acceler-
ating on slippery roads.
■ EPS (Electric Power Steering)
Employs an electric motor to reduce the amount of effort needed to turn
the steering wheel.
■VDIM (Vehicle Dynamics Integrated Management)
Provides integrated control of the ABS, brake assist, VSC, traction control
and EPS systems.
Maintains vehicle stability when swerving on slippery road surfaces by
controlling the brakes, engine output, and the movement of the front
wheels.

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When the VSC/traction control are operatingIf the vehicle is in danger of slip-
ping, or if the front wheels (2WD
models) or all wheels (AWD mod-
els) spin, the slip indicator light
flashes to indicate that the VSC/
traction control have been
engaged.
A buzzer (intermittent) sounds to
indicate that VSC is operating.
■Sounds and vibrations caused by the ABS, brake assist, VSC and traction control
●A sound may be heard from the engine compartment 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 operat-
ing. 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 after the vehicle comes to a stop.
• The brake pedal may pulsate slightly after the ABS is activated.
• The brake pedal may move down slightly after the ABS is activated.
■Reduced effectiveness of EPS
The effectiveness of EPS 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 system should return to nor-
mal within 10 minutes.

176
2-5. Driving information
RX400h_U
CAUTION
■Off-road driving precautions
Always observe the following precautions to minimize the risk of serious personal
injury or damage to your vehicle:
●Drive carefully when off the road. Do not take unnecessary risks by driving in
dangerous places.
●Do not grip the steering wheel spokes when driving off-road. A bad bump could
jerk the wheel and injure your hands. Keep both hands and especially your
thumbs on the outside of the rim.
●Always check your brakes for effectiveness immediately after driving in sand,
mud, water or snow.
●After driving through tall grass, mud, rock, sand, rivers, etc., check that there is no
grass, bush, paper, rags, stone, sand, etc. adhering or trapped on the underbody.
Clear off any such matter from the underbody. If the vehicle is used with these
materials trapped or adhering to the underbody, a breakdown or fire could occur.
●When driving off-road or in rugged terrain, do not drive at excessive speeds,
jump, make sharp turns, strike objects, etc. This may cause loss of control or vehi-
cle rollover causing death or serious injury. You are also risking expensive dam-
age to your vehicle’s suspension and chassis.
NOTICE
■To prevent the water damage
Take all necessary safety measures to ensure that water damage to the hybrid bat-
tery, hybrid system or other components does not occur.
●Water entering the engine compartment may cause severe damage to the hybrid
system. Water entering the interior may cause the hybrid battery stowed under
the rear seats to short circuit.
●Water entering the hybrid transaxle will cause deterioration in transmission qual-
ity. The malfunction indicator may come on, and the vehicle may not be drivable.
●Water can wash the grease from wheel bearings, causing rusting and premature
failure, and may also enter the transaxle case, reducing the gear oil’s lubricating
qualities.

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2-5. Driving information
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CAUTION
■Storage precautions
●Do not place anything on the luggage cover, and do not stack anything in the lug-
gage compartment higher than the seatbacks.
Such items may be thrown about and possibly injure people in the vehicle during
sudden braking or in an accident.
●Do not drive with objects on top of the instrument panel.
They may interfere with the driver’s field of view or move during sharp accelera-
tion or turning, thus impairing the driver’s control of the vehicle. In an accident
they may injure the vehicle occupants.
●Secure all items in the occupant compartment, as they may shift and injure some-
one during an accident or sudden braking.
●Never allow anyone to ride in the luggage compartment. It is not designed for
passengers. They should ride in their seats with their seat belts properly fastened.
Otherwise, they are much more likely to suffer serious bodily injury, in the event
of sudden braking or a collision.
■Capacity and distribution
●Improper loading may cause deterioration of steering or braking control result-
ing in an accident which may cause death or serious injury.
●Do not exceed the maximum axle weight rating or the total vehicle weight rating.
●Even if the total load of occupant's weight and the cargo load is less than the total
load capacity, do not apply the load unevenly.

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When driving
RX400h_U
Vehicle load limits
■Total load capacity and seating capacity
These details are also described on the tire and loading information label.
(→ P. 3 4 0 )
CAUTION
■Overloading the vehicle
Do not overload the vehicle.
It may not only cause damage to the tires, but also degrade steering and braking
ability, resulting in an accident.
Vehicle load limits include total load capacity, seating capacity, towing
capacity and cargo capacity.
■Total load capacity: 925 lb. (420 kg)
Total load capacity means the combined weight of occupants, cargo and
luggage.
■Seating capacity: 5 occupants (Front 2, Rear 3)
Seating capacity means the maximum number of occupants whose esti-
mated average weight is 150 lb. (68 kg) per person.
Even if the number of occupants are within the seating capacity, do not
exceed the total load capacity.
■Towing capacity
Without towing package: 2000 lb. (907 kg)
With towing package: 3500 lb. (1588 kg)
Towing capacity means the maximum gross trailer weight (trailer weight
plus its cargo weight) that your vehicle is able to tow.
■Cargo capacity
Cargo capacity may increase or decrease depending on the weight and
the number of occupants.

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When driving
RX400h_U
Trailer towing tipsYour vehicle will handle differently when towing a trailer. The 3 main
causes of vehicle-trailer accidents are driver error, excessive speed and
improper trailer loading. Keep the following in mind when towing.
● Before starting out, check the trailer lights and the vehicle-trailer con-
nections. Recheck after driving a short distance.
● Practice turning, stopping and rever sing with the trailer attached in an
area away from traffic until you become accustomed to the feel of the
vehicle.
● Reversing with a trailer attached is difficult and requires practice. Grip
the bottom of the steering wheel and move your hand to the left to
move the trailer to the left. Move your hand to the right to move the
trailer to right. (This is generally opposite to reversing without a trailer
attached.) Avoid sharp or prolon ged turning. Have someone guide
you when reversing to reduce the risk of an accident.
● As stopping distance is increased when towing a trailer, vehicle-to-
vehicle distance should be increased. For each 10 mph (16 km/h) of
speed, allow at least one vehicle and trailer length.
NOTICE
■Safety chain
A safety chain must always be used between the towing vehicle and the trailer.
Leave sufficient slack in the chain for turns. The chain should cross under the trailer
tongue to prevent the tongue from dropping to the ground in the case that it
becomes damaged or separated. For the correct safety chain installation proce-
dure, ask your Lexus dealer.
■Do not directly splice trailer lights
Directly splicing trailer lights may damage your vehicle's electrical system and
cause a malfunction.

194
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Avoid sudden braking as you may sk id, resulting in jackknifing and loss
of control. This is especially true on wet or slippery surfaces.
● Avoid jerky starts or sudden acceleration.
● Avoid jerky steering and sharp turns, and slow down before making
turns.
● Note that when making a turn, the trailer wheels will be closer than the
vehicle wheels to the inside of the turn. Compensate by making a
larger than normal turning radius.
● Crosswinds and rough roads will adversely affect handling of your
vehicle and trailer, causing sway. Periodically check the rear to prepare
for being passed by large trucks or buses, which may cause your vehi-
cle and trailer to sway. If swaying occurs, firmly grip the steering wheel,
reduce speed immediately but gradually, and steer straight ahead.
Never increase speed. If you make no extreme correction with the
steering or brakes, your vehicle and trailer will stabilize.
● Take care when passing other vehicles. Passing requires considerable
distance. After passing a vehicle, do not forget the length of your
trailer, and be sure you have plenty of room before changing lanes.
● Due to the added load of the trailer, your vehicle's hybrid system may
overheat on hot days (at temperatures over 85°F [30°C]) when driv-
ing up a long or steep grade. If the coolant temperature gauge indi-
cates overheating, immediately turn off the air conditioning (if in use),
pull your vehicle off the road and stop in a safe spot. ( →P. 4 2 4 )