brakes Lexus IS250 2012 Owner's Manual

132
2-1. Driving procedures
IS350/250_U
■Starting off on a hill (vehicles with an automatic transmission)
Hill-start assist control will operate. (→P. 1 9 6 )
■Driving in the rain
●Drive carefully when it is raining, because visibility will be reduced, the windows
may become fogged-up, and the road will be slippery.
●Drive carefully when it starts to rain, because the road surface will be especially
slippery.
●Refrain from high speeds when driving on an expressway in the rain, because
there may be a layer of water between the tires and the road surface, preventing
the steering and brakes from operating properly.
■Engine speed while driving
In the following conditions, the engine spee d may become high while driving. This is
due to automatic up-shifting control or down-shifting implementation to meet driv-
ing conditions. It does not indicate sudden acceleration.
●The vehicle is judged to be driving uphill or downhill
●When the accelerator pedal is released
■Breaking in your new Lexus
To extend the life of the vehicle, the following precautions are recommended to
observe:
●For the first 186 miles (300 km):
Avoid sudden stops.
●For the first 621 miles (1000 km):
• Do not drive at extremely high speeds.
• Avoid sudden acceleration.
• Do not drive continuously in the low gears.
• Do not drive at a constant speed for extended periods.
■Drum-in-disc type parking brake system
Your vehicle has a drum-in-disc type parking brake system. This type of brake sys-
tem needs bedding-down of the brake shoes periodically or whenever the parking
brake shoes and/or drum are replaced. Have your Lexus dealer perform the bed-
ding down.

134
2-1. Driving procedures
IS350/250_U
CAUTION
●With automatic transmission vehicles, do not shift the shift lever to P while the
vehicle is moving.
Doing so can damage the transmission and may result in a loss of vehicle control.
●Do not shift the shift lever to R while the vehicle is moving forward.
Doing so can damage the transmission and may result in a loss of vehicle control.
●Do not shift the shift lever to D (vehicles with an automatic transmission) or 1
(vehicles with a manual transmission) while the vehicle is moving backward.
Doing so can damage the transmission and may result in a loss of vehicle control.
●Moving the shift lever to N while the vehicle is moving will disengage the engine
from the transmission. Engine braking is not available when N is selected.
●During normal driving, do not turn off the engine. Turning the engine off while
driving will not cause loss of steering or braking control, but the power assist to
these systems will be lost. This will make it more difficult to steer and brake, so you
should pull over and stop the vehicle as soon as it is safe to do so.
However, in the event of an emergency, such as if it becomes impossible to stop
the vehicle in the normal way: →P. 5 1 8
●Use engine braking (downshift) to maintain a safe speed when driving down a
steep hill.
Using the brakes continuously may cause the brakes to overheat and lose effec-
tiveness. (→ P. 1 4 7 )
●When stopped on an inclined surface, use the brake pedal and parking brake to
prevent the vehicle from rolling backward or forward and causing an accident.
●Do not adjust the position of the steering wheel, the seat, or the inside or outside
rear view mirrors while driving.
Doing so may result in a loss of vehicle control that can cause accidents that may
result in death or serious injury.

135
2-1. Driving procedures
2
When driving
IS350/250_U
CAUTION
●Always check that all passengers' arms, heads or other parts of their bodies are
not outside the vehicle, as this may result in death or serious injury.
●Do not drive the vehicle off-road.
This is not a AWD vehicle designed for real off-road driving. Proceed with all due
caution if it becomes unavoidable to drive off-road.
●Do not drive across river crossings or through other bodies of water.
This may cause electric/electronic components to short circuit, damage the
engine or cause other serious damage to the vehicle.
●Do not drive in excess of the speed limit. Even if the legal speed limit permits it, do
not drive over 85 mph (140 km/h) unless your vehicle has high-speed capability
tires. Driving over 85 mph (140 km/h) may result in tire failure, loss of control and
possible injury. Be sure to consult a tire dealer to determine whether the tires on
your vehicle are high-speed capability tires or not before driving at such speeds.
■When driving on slippery road surfaces
●Sudden braking, acceleration and steering may cause tire slippage and reduce
your ability to control the vehicle, resulting in an accident.
●Sudden changes in engine speed, such as engine braking caused by up-shifting
or down-shifting, may cause the vehicle to skid, resulting in an accident.
●After driving through a puddle, lightly depress the brake pedal to make sure that
the brakes are functioning properly. Wet brake pads may prevent the brakes from
functioning properly. If the brakes on only one side are wet and not functioning
properly, steering control may be affected, resulting in an accident.

138
2-1. Driving procedures
IS350/250_U
CAUTION
■When taking a nap in the vehicle
Always turn the engine off. Otherwise, you may accidentally move the shift lever or
depress the accelerator pedal, which could cause an accident or fire due to engine
overheating. Additionally, if the vehicle is parked in a poorly ventilated area, exhaust
gases may collect and enter the vehicle, leading to death or a serious health hazard.
■When braking the vehicle
●When the brakes are wet, drive more cautiously.
Braking distance increases when the brakes are wet, and may cause one side of
the vehicle to brake differently than the other side. Also the parking brake may
not securely hold the vehicle.
●If the power brake assist function does not operate, do not follow other vehicles
closely and avoid downhills or sharp turns that require braking.
In this case, braking is still possible, but it will require more force on the pedal than
usual. Braking distance may also increase.
●Do not pump the brake pedal if the engine stalls.
Each push on the brake pedal uses up the reserve for the power-assisted brakes.
●The brake system consists of 2 individual hydraulic systems: if one of the systems
fails, the other will still operate. In this case, the brake pedal should be depressed
more firmly than usual and braking distance becomes longer.
Do not drive your vehicle with only a single brake system. Have your brakes fixed
immediately.
■If the vehicle becomes stuck or bogged (AWD models)
Do not spin the wheels recklessly when any of the tires is up in the air, or stuck in
sand or mud, etc. This may damage the drive system components or propel the
vehicle forward (or in another direction) and cause an accident.

187
2-4. Using other driving systems
2
When driving
IS350/250_U
■Adjusting the set speed
To change the set speed, operate the lever until the desired set
speed is obtained.
Increases the speed
Decreases the speed
Fine adjustment: Momentarily
move the lever in the desired
direction.
Large adjustment: Hold the
lever in the desired direction.
The set speed will be increased or decreased as follows:
Fine adjustment: By approximately 1 mph (1.6 km/h) each time the lever is
operated.
Large adjustment: The set speed can be increased or decreased continu-
ally until the lever is released.
■ Canceling and resuming the constant speed control
Pulling the lever toward you
cancels the constant speed
control.
The speed setting is also can-
celed when the brakes are
applied or the clutch pedal
(manual transmission only) is
depressed.
Pushing the lever up resumes
the constant speed control.
Resuming is available when the
vehicle speed is more than
approximately 25 mph (40
km/h)

194
2-4. Using other driving systems
IS350/250_U
■Sensor detection information
●Certain vehicle conditions and the surrounding environment may affect the
ability of the sensor to correctly detect obstacles. Particular instances where this
may occur are listed below.
• There is dirt, snow or ice on the sensor.
• The sensor is frozen.
•The sensor is covered in any way.
• The vehicle is leaning considerably to one side.
• On an extremely bumpy road, on an incline, on gravel, or on grass.
• The vicinity of the vehicle is noisy due to vehicle horns, motorcycle engines,air brakes of large vehicles, or other loud noises producing ultrasonic waves.
• There is another vehicle equipped with parking assist sensors in the vicinity.
• The sensor is coated with a sheet of spray or heavy rain.
• The vehicle is equipped with a fender pole or wireless antenna.
• Towing eyelets are installed.
• The bumper or sensor receives a strong impact.
• The vehicle is approaching a tall or curved curb.
• In harsh sunlight or intense cold weather.
In addition to the examples above, there are instances in which, because of their
shapes, signs and other objects may be judged by the sensor to be closer than they
are.
●The shape of the obstacle may prevent the sensor from detecting it. Pay particu-
lar attention to the following obstacles.
• Wires, fences, ropes etc.
• Cotton, snow and other materials that absorb radio waves
• Sharply-angled objects
• Low obstacles
• Tall obstacles with upper sections projecting outwards in the direction of your
vehicle
■When the display flashes and a message is displayed
→ P. 4 8 1

196
2-4. Using other driving systems
IS350/250_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.
■TRAC (Traction Control)
Maintains drive power and prevents the rear wheels (2WD models) or all
wheels (AWD models) from spinning wh en starting the vehicle or acceler-
ating on slippery roads.
■ Hill-start assist control (vehicles with an automatic transmission)
Helps to prevent the vehicle from rolling backward when starting on an
incline or slippery slope.
■EPS (Electric Power Steering)
Employs an electric motor to reduce the amount of effort needed to turn
the steering wheel.

197
2-4. Using other driving systems
2
When driving
IS350/250_U
When the VSC/TRAC/hill-start assist control systems are operatingThe slip indicator light flashes to
indicate that the VSC/TRAC/hill-
start assist control systems have
been engaged.
The stop lights and high mounted
stoplight turn on when the hill-start
assist control system is operating.
■VDIM (Vehicle Dynamics Integrated Management)
Provides integrated control of the ABS, brake assist, TRAC, VSC, hill-start
assist control, and EPS systems.
Helps to maintain vehicle stability when swerving on slippery road sur-
faces by controlling the brakes, engine output and steering assist.

206
2-5. Driving information
IS350/250_U
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 or purchase a set of
tire chains for the rear tires.
Ensure that all tires are the specified size and the same brand, and that
chains match the size of the tires.
■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.

388
4-2. Maintenance
IS350/250_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?
Clutch pedal• Moves smoothly?
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 9 )
Parking brake
• 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?