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■When the brake system operates continuously
The brake actuator may overheat. In this case, the TRAC or Active TRAC and hill-
start assist control systems will stop operating, a buzzer will sound and the TRAC
OFF will be shown on the multi-information display. Refrain from using the system
until the message goes off. (There is no problem with continuing normal driving.)
■If the slip indicator comes on...
It may indicate a malfunction in the VSC, TRAC/Active TRAC or hill-start assist
control system. Consult your Lexus dealer.
CAUTION
■The ABS/Multi Terrain ABS does not operate effectively when
●Tires with inadequate gripping ability are used (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/Multi Terrain ABS is operating may exceed
that of normal conditions
The ABS/Multi Terrain ABS is not designed to shorten the vehicle’s stopping dis-
tance. Always maintain a safe distance from the vehicle in front of you in the follow-
ing 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 surfaces
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PCS (Pre-Collision System)∗
∗: If equipped
When the radar sensor detects that a frontal collision is highly likely or
even unavoidable, safety systems such as the brakes and seat belts are
automatically engaged to lessen im pact as well as vehicle damage.
■Pre-collision seat belts (front seat belts only)
If the system detects that a collision is unavoidable, the system will
retract the seat belt before the collision occurs.
The same will happen if the driver makes an emergency braking or
loses control of the vehicle. ( →P. 9 1 )
However, when the VSC system is disabled, the system will not
operate in the event of skidding.
■ Pre-collision brake assist
When there is a high possibility of a frontal collision, the system
applies greater braking force in relation to how strongly the brake
pedal is depressed.
■ Pre-collision braking
When there is a high possibility of a frontal collision, the system
warns the driver using a warning light, warning display and buzzer. If
the system determines that a collision is unavoidable, the brakes are
automatically applied to reduce the collision speed. Pre-collision
braking can be disabled using the pre-collision braking off switch.
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■The pre-collision system is operational when
●Pre-collision seat belts (situation 1):
• Vehicle speed is greater than about 4 mph (5 km/h).
• The speed at which your vehicle is approaching the obstacle or the vehiclerunning ahead of you is greater than about 19 mph (30 km/h).
• The front occupants are wearing a seat belt.
●Pre-collision seat belts (situation 2):
• Vehicle speed greater than about 19 mph (30 km/h).
• The system detects sudden braking or skidding.
• The front occupants are wearing a seat belt.
●Pre-collision brake assist:
• Vehicle speed is greater than about 19 mph (30 km/h).
• The speed at which your vehicle is approaching the obstacle or the vehicle running ahead of you is greater than about 19 mph (30 km/h).
• The brake pedal is depressed.
●Pre-collision braking:
• The pre-collision braking off switch is not pressed.
• Vehicle speed is greater than about 10 mph (15 km/h).
• The speed at which your vehicle is approaching the obstacle or the vehicle running ahead of you is greater than about 10 mph (15 km/h).
●AVS (Adaptive Variable Suspension System) control (if equipped):
• Vehicle speed is greater than about 4 mph (5 km/h).
• The speed at which your vehicle is approaching the obstacle or the vehicle
running ahead of you is greater than about 19 mph (30 km/h).
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●Pre-collision alert braking (vehicle with driver monitor system):
• The pre-collision braking off switch is not pressed.
• The system determines that the driver is not facing forward.
• Vehicle speed is greater than about 10 mph (15 km/h).
• The speed at which your vehicle is approaching the vehicle running ahead ofyou is greater than about 25 mph (40 km/h).
■Conditions that may trigger the system even if there is no possibility of a collision
●When there is an object by the roadside at the entrance to a curve
●When passing an oncoming vehicle on a curve
●When driving over a narrow iron bridge
●When there is a metal object on the road surface
●When driving on an uneven road surface
●When passing an oncoming vehicle on a left-turn
●When your vehicle rapidly closes on the vehicle in front
●When a grade separation/interchange, sign, billboard, or other structure
appears to be directly in the vehicle’s line of travel
●When a billboard or other metallic structure appears to be in the direct line of
travel due to driving on a hill.
●When there are excessive changes in the vehicle height (when it tilts forwards
or backwards)
●When there is an abnormality in the radar sensor
●When passing through certain toll gates
●When driving on a bridge
When the system is activated in the situations described above, there is also a possi-
bility that the seat belts will retract quickly and the brakes will be applied with a force
greater than normal. When the seat belt is locked in the restricted position, stop the
vehicle in a safe place, release the seat belt and refasten it.
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CAUTION
■Limitations of the pre-collision system
Do not overly rely on the pre-collision system. Always drive safely, taking care to
observe your surroundings and checking for any obstacles or other road hazards.
Failure to do so may cause an accident resulting in death or serious injury.
■Cautions regarding the assist contents of the system
By means of alarms and brake control, the pre-collision system is intended to assist
the driver in avoiding collisions through the process of LOOK-JUDGE-ACT. There
are limits to the degree of assistance the system can provide, so please keep in mind
the following important points.
●Assisting the driver in watching the road
The pre-collision system is only able to detect obstacles directly in front of the
vehicle, and only within a limited range. It is not a mechanism that allows careless
or inattentive driving, and it is not a system that can assist the driver in low-visibil-
ity conditions. It is still necessary for the driver to pay close attention to the vehi-
cle’s surroundings.
●Assisting the driver in making correct judgment
When attempting to estimate the possibility of a collision, the only data available
to the pre-collision system is that from obstacles it has detected directly in front of
the vehicle. Therefore, it is absolutely necessary for the driver to remain vigilant
and to determine whether or not there is a possibility of collision in any given situ-
ation.
●Assisting the driver in taking action
The pre-collision system’s braking assist feature is designed to help reduce the
severity of a collision, and so only acts when the system has judged that a collision
is unavoidable. This system by itself is not capable of automatically avoiding a col-
lision or bringing the vehicle to a stop safety. For this reason, when encountering a
dangerous situation the driver must take direct and immediate action in order to
ensure the safety of all involved.
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CAUTION
■When the sensor may not be correctly detecting the vehicle ahead
Apply the brakes as necessary in any of the following situations.
●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.)
●Vehicles that cut in suddenly
●Vehicles with small rear ends (trailers with no load on board etc.)
●Motorcycles traveling in the same lane
■Handling the radar sensor
Observe the following to ensure the pre-collision system can function effectively:
●Keep the sensor and front grille cover clean at all times.
Clean the sensor and front grille cover with a soft cloth so you do not mark or
damage them.
●Do not subject the sensor or surrounding area to a strong impact.
If the sensor moves even slightly off position, the system may become inaccurate
or malfunction. If the sensor or surrounding area is subject to a strong impact,
always have the area inspected and adjusted by your Lexus dealer.
●Do not disassemble the sensor.
●Do not attach accessories or stickers to the sensor, grille cover or surrounding
area.
●Do not modify or paint the sensor and grille cover.
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CAUTION
■Off-road driving precautions
Always observe the following precautions to minimize the risk of death, serious
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.
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NOTICE
■To prevent the water damage
Take all necessary safety measures to ensure that water damage to the engine or
other components does not occur.
●Water entering the engine air intake will cause severe engine damage.
●Water entering the automatic transmission will cause deterioration in shift quality,
locking up of your transmission accompanied by vibration, and ultimately dam-
age.
●Water can wash the grease from wheel bearings, causing rusting and premature
failure, and may also enter the differentials, transmission and transfer case, reduc-
ing the gear oil’s lubricating qualities.
■When you drive through water
If driving through water, such as when crossing shallow streams, first check the
depth of the water and the bottom of the riverbed for firmness. Drive slowly and
avoid deep water.
■Inspection after off-road driving
●Sand and mud that has accumulated in brake drums and around brake discs may
affect braking efficiency and may damage brake system components.
●Always perform a maintenance inspection after each day of off-road driving that
has taken you through rough terrain, sand, mud, or water. For scheduled mainte-
nance information, refer to the “Warranty and Services Guide”, “Owner’s Manual
Supplement” or “Scheduled Maintenance”.
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