2008 LEXUS RX400H Owners Manual

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CAUTION
■Before using dynamic laser cruise control
Do not overly rely on vehicle-to-vehicle distance control.
Be aware of the set vehicle speed. If automatic deceleration/acceleration is not
appropriate, adjust the vehicle speed, as well as the distance between your vehicle
and vehicles ahead by applying the brakes, etc.
■To avoid inadvertent cruise control activation
Keep the ON-OFF button off when not in use.
■Situations unsuitable for dynamic laser cruise control
Do not use dynamic laser cruise control in any of the following situations.
Doing so may result in inappropriate control of speed and could cause serious or
fatal accident.
●In heavy traffic
●On roads with sharp bends
●On winding roads
●On slippery roads, such as those covered with rain, ice or snow
●Where there are sudden changes between sharp up and down gradients
●At entrances to expressways
●When weather conditions are bad enough that they may prevent the sensors
from functioning correctly (fog, snow, sandstorm, etc.)
●When buzzer can be heard often

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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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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.

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CAUTION
Any of the following conditions may result in an accident which could cause death or
serious injury:
■The ABS does not operate effectively when
●The limits of tire gripping performance have been exceeded.
●The vehicle hydroplanes while driving at high speed on the wet or slick road.
■Stopping distance when the ABS is operating will exceed that of normal condi-
tions
The ABS is not designed to shorten the vehicle’s stopping distance. Always main-
tain a safe distance from the vehicle in front of you 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 roads with uneven roads
■Traction control may not operate effectively when
Directional control and power may not be achievable while driving on slippery road
surfaces, even if the traction control system is operating.
Do not drive the vehicle in conditions where stability and power may be lost.

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CAUTION
■When the slip indicator flashes and a warning buzzer sounds
This situation occurs immediately while VSC is activated. Always drive carefully.
Reckless driving may cause an accident. Exercise particular care when the indica-
tor light flashes and a buzzer sounds.
■Replacing tires
Make sure that all tires are of the same size, brand, tread pattern and total load
capacity. In addition, make sure that the tires are inflated to the recommended tire
pressure level.
The ABS and VSC systems will not function correctly if different tires are fitted on
the vehicle.
Contact your Lexus dealer for further information when replacing tires or wheels.
■Handling of tires and suspension
Using tires with any kind of problem or modifying the suspension will affect the
VDIM, and may cause the system to malfunction.

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2-5. Driving information
Utility vehicle precautions
Utility vehicle feature● Specific design characteristics give it a higher center of gravity than
ordinary passenger cars. This vehicle design feature causes this type of
vehicle to be more likely to rollover. And, utility vehicles have a signifi-
cantly higher rollover rate than other types of vehicles.
● It is not designed for cornering at the same speeds as ordinary passen-
ger cars any more than low-slung sports cars designed to perform sat-
isfactorily under off-road conditions. Therefore, sharp turns at
excessive speeds may cause rollover.
This vehicle belongs to the utility vehicle class, which has higher ground
clearance and narrower tread in relation to the height of its center of grav-
ity.

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CAUTION
■Utility vehicle precautions
Always observe the following precautions to minimize the risk of serious personal
injury or damage to your vehicle:
●In a rollover crash, an unbelted person is significantly more likely to die than a
person wearing a seat belt. Therefore, the driver and all passengers should fasten
their seat belts whenever the vehicle is moving.
●Avoid sharp turns or abrupt maneuvers, if at all possible.
Failure to operate this vehicle correctly may result in loss of control or vehicle roll-
over causing death or serious injury.
●Loading cargo on the roof luggage carrier will make the center of the vehicle
gravity higher. Avoid high speeds, sudden starts, sharp turns, sudden braking or
abrupt maneuvers, otherwise it may result in loss of control or vehicle rollover
due to failure to operate this vehicle correctly.
●Always slow down in gusty crosswinds. Because of its profile and higher center of
gravity, your vehicle is more sensitive to side winds than an ordinary passenger
car. Slowing down will allow you to have better control.
●Do not drive horizontally across steep slopes. Driving straight up or straight down
is preferred. Your vehicle (or any similar off-road vehicle) can tip over sideways
much more easily than forward or backward.