brake Lexus IS F 2012 Owner's Guide

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2-4. Using other driving systems
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When driving
IS F_U
PCS (Pre-Collision System)∗
Radar sensorDetects vehicles or other obsta-
cles on or near the road ahead and
determines whether a collision is
imminent based on the position,
speed, and heading of the obsta-
cles. Grille cover
Radar sensor
∗: If equipped
When the radar sensor detects possibility of a frontal collision, the pre-
collision system such as the brakes and seat belts are automatically
engaged to lessen impact and injuries to occupants as well as vehicle dam-
age.
■Pre-collision seat belts
If the pre-collision sensor detects that a collision is unavoidable, the pre-
collision 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. 6 6 )
However, the system will not operate in the event of skidding when the
VSC system are disabled.
■ 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 unavoi dable, the brakes are automatically
applied to reduce the collision speed. The pre-collision braking function
can be turned on and off using the satellite switch.

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Disabling the pre-collision braking
The pre-collision braking function
can be turned on and off using the
satellite switch. (→P. 343)
Press “ <” or “ >” to display the
“PCS BRAKE” setting ( ). Then,
press the “ON/OFF” button in the
middle of the switch to select either
“ON” or “OFF” ( ).
It may take approximately 3 sec-
onds for the display to change after
the satellite switch is operated.
The “PCS” warning light flashes
when “OFF” is selected.
■Obstacles not detected
The sensor cannot detect plastic obstacles such as pylons. There may also be occa-
sions when the sensor cannot detect pedestrians, animals, bicycles, motorcycles,
trees, or snowdrifts.

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■The pre-collision system is operational when
●Pre-collision seat belts (type A):
• Vehicle speed is above 4 mph (5 km/h).
• The speed at which your vehicle is approaching the obstacle or oncomingvehicle exceeds about 19 mph (30 km/h).
• The front occupants are wearing a seat belt.
●Pre-collision seat belts (type B):
• Vehicle speed exceeds 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 above 19 mph (30 km/h).
• The speed at which your vehicle is approaching the obstacle or the vehicle is greater than 19 to 25 mph (30 to 40 km/h).
• The brake pedal is depressed.
●Pre-collision braking
• The pre-collision braking function is activated.
• Vehicle speed is above 10 mph (15 km/h).
• The relative speed difference between your vehicle and another vehicle that is forward of your vehicle, or the speed at which your vehicle is approaching
an obstacle is greater than 10 mph (15 km/h).
■Conditions that may trigger the system even if there is no possibility of 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 an overhead billboard or other metallic structure appears to be in the
vehicle’s direct line of travel due to driving on a hill.

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●When an extreme change in vehicle height occurs
●When the axis of the radar is out of adjustment
●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 retracted position, stop the
vehicle in a safe place, release the seat belt and refasten.
■When there is a malfunction in the system
Warning lights and/or warning messages will turn on or flash. ( →P. 463, 473)
■Situations in which the pre-collision system does not function properly
The system may not function effectively in situations such as the following:
●On roads with sharp bends or uneven surfaces
●If a vehicle suddenly moves in front of your vehicle, such as at an intersection
●If a vehicle suddenly cuts in front of your vehicle, such as when overtaking
●In inclement weather such as heavy rain, fog, snow or sand storms
●When your vehicle is skidding with the VSC system off
●When an extreme change in vehicle height occurs
●When the axis of the radar is out of adjustment
■Automatic cancelation of the pre-collision system
When a malfunction occurs due to sensor contamination, etc. that results in the
sensors being unable to detect obstacles, the pre-collision system will be automati-
cally disabled. In this case, the system will not activate even if there is a collision pos-
sibility.

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CAUTION
■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 safely. 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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2-5. Driving information
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CAUTION
■Things that must not be carried in the trunk
The following things may cause a fire if loaded in the trunk.
●Receptacles containing gasoline
●Aerosol cans
■Storage precautions
Observe the following precautions.
Failing to do so may result in death or serious injury.
●Do not place cargo or luggage in or on the following locations as the item may
get under the brake or accelerator pedal and prevent pedals from being
depressed properly, block the driver's vision, or hit the driver or passengers,
causing an accident.
• At the feet of the driver
• On the front passenger or rear seats (when stacking items)
• Package tray (behind the rear seatback)
• Instrument panel
•Dashboard
●Secure all items in the occupant compartment, as they may shift and injure some-
one during sudden braking, sudden swerving or an accident.
■Luggage capacity and distribution
Observe the following precautions. Failure to do so will not only put load on the
tires, but also reduce steering and braking performance. This could lead to an acci-
dent resulting in serious injury or even death.
●Do not overload the vehicle.
●Do not apply load to the vehicle unevenly.

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2-5. Driving information
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Winter driving tips
Carry out the necessary preparations and inspections before driving the
vehicle in winter. Always drive the vehicle in a manner appropriate to the
prevailing weather conditions.
■Pre-winter preparations
● Use fluids that are appropriate to the prevailing outside tempera-
tures.
• Engine oil
• Engine coolant
• Washer fluid
● Have a service technician inspect the level and specific gravity of
battery electrolyte.
● Have the vehicle fitted with four snow tires.
Ensure that all tires are the specified size and the same brand.
■Before driving the vehicle
Perform the following according to the driving conditions.
● Do not try to forcibly open a window or move a wiper that is fro-
zen. Pour warm water over the frozen area to melt the ice. Wipe
away the water immediately 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.
● Remove any ice that has accumulated on the vehicle chassis.
● Periodically check for and remove any excess ice or snow that
may have accumulated in the wheel well or on the brakes.

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CAUTION
■Driving with snow tires
Observe the following precautions to reduce the risk of accidents.
Failing to do so may result in a loss of vehicle control and cause death or serious
injury.
●Use tires of the size specified for your vehicle.
●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.
NOTICE
■Driving with tire chains
Do not fit tire chains. Tire chains may damage the vehicle body and adversely affect
driving performance.
■Repairing or replacing snow tires
Request repairs of and obtain replacement snow tires from Lexus dealers or legiti-
mate tire retailers.
This is because the removal and attachment of snow tires affects the operation of
the tire pressure warning system.
■When driving the vehicle
Accelerate the vehicle slowly and drive at a reduced speed suitable
to road conditions.
■ When parking the vehicle
Park the vehicle and move the shift lever to P without setting the
parking brake. The parking brake may freeze up, preventing it from
being released. If necessary, block the wheels to prevent inadvert-
ent sliding or creeping.

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4-2. Maintenance
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General maintenance
Engine compartment
ItemsCheck points
BatteryMaintenance-free. (→P. 4 0 6 )
Brake fluidAt the correct level? ( →P. 404)
Engine coolantAt the correct level? ( →P. 4 0 2 )
Engine oilAt the correct level? ( →P. 399)
Exhaust systemNo fumes or strange sounds?
Radiator/condenser/hosesNot blocked with foreign matter?
(→ P. 4 0 4 )
Wa s h e r f l u i dAt the correct level? ( →P. 4 0 9 )
Listed below are the general maintenance items that should be performed
at the intervals specified in the “Warranty and Services Guide” or “Owners
Manual Supplement”. It is recommended that any problem you notice
should be brought to the attention of your Lexus dealer or qualified service
shop for advice.

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4-2. Maintenance
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Maintenance and care
IS F_U
Vehicle interior
ItemsCheck points
Accelerator pedal• Moves smoothly (without uneven pedal effort or catching)?
Automatic transmission “Park”
mechanism• Can the vehicle be held securely on an incline with the shift lever in
P?
Brake pedal
• Moves smoothly?
• Does it have appropriate clearance and correct amount of free play?
Brakes
• Not pull to one side when applied?
• Loss of brake effectiveness?
• Spongy feeling brake pedal?
• Pedal almost touches floor?
Head restraints• Move smoothly and lock securely?
Indicators/buzzers•Function properly?
Lights
• Do all the lights come on?
• Headlights aimed correctly? (→ P. 4 4 5 )
Pa r k i n g b r a ke
• Moves smoothly?
• Can hold the vehicle securely on
an incline?
Seat belts
• Does the seat belt system operate smoothly?
• Are the belts undamaged?
Seats• Do the seat controls operate prop- erly?