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CAUTION
Conditions under which the vehicle-to-vehicle distance control may not
function correctly
Apply the brakes as necessary in the following conditions as the radar sen-
sor may not be able to correctly detect vehicles ahead, and a fatal or serious
accident may result:
When water or snow thrown up by the surrounding vehicles hinders the
functioning of the sensor
When your vehicle is pointing upwards (caused by a heavy load in the
trunk etc.)
When the road curves or when the lanes are narrow
When steering wheel operation or your position in the lane is unstable
When the vehicle ahead of you decelerates suddenly
Handling the radar sensor
Observe the following to ensure the cruise control system can function
effectively.
Otherwise, the system may not function correctly and could result in an
accident.
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 malfunc-
tion. If the sensor or surrounding area is subject to a strong impact, always
have the area inspected and adjusted by any authorized Lexus dealer or
repairer, or another duly qualified and equipped professional.
Do not disassemble the sensor.
Do not attach accessories or stickers to the sensor, grille cover or sur-
rounding area.
Do not modify or paint the sensor and grille cover.
Do not replace them with non-genuine parts.
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Driving assist systems
To help enhance driving safety and performance, the following sys-
tems 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.
TRC (Traction Control)
Maintains drive power and prevents the rear wheels from spinning
when starting the vehicle or accelerating on slippery roads.
Hill-start assist control (vehicles with an automatic transmis-
sion)
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.
PCS (Pre-Crash Safety System) (if equipped)
P. 230
VDIM (Vehicle Dynamics Integrated Management)
Provides integrated control of the ABS, brake assist, TRC, VSC,
hill-start assist control, and EPS systems.
Helps to maintain vehicle stability when swerving on slippery road
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When driving
IS250/220d/200d_EE
When the VSC/TRC/hill-start assist control systems are operating
The slip indicator flashes to
indicate that the VSC/TRC/hill-
start assist control systems have
been engaged.
The stop lights and high
mounted stoplight turn on when
the hill-start assist control sys-
tem is operating.
To disable TRC/VSC
If the vehicle gets stuck in fresh snow or mud, TRC and VSC may
reduce power from the engine to the wheels. You may need to turn
the system off to enable you to rock the vehicle in order to free it.
Turning off TRC
Quickly push and release the
switch to turn off TRC
A message will be shown on the
multi-information display.
Push the switch again to turn
the system back on.
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When driving
IS250/220d/200d_EE
Sounds and vibrations caused by the ABS, brake assist, VSC, TRC and hill-
start assist control systems
A sound may be heard from the engine compartment if the brake pedal is
depressed repeatedly when the engine 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
operating. 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 when the ABS is activated.
• The brake pedal may move down slightly after the ABS is activated.
Hill-start assist control is operational when
The shift lever is in the D or S position.
The brake pedal is not depressed.
The vehicle rolls backward.
EPS operation sound
When the steering wheel operates, a motor sound (whirring sound) may be
heard. This does not indicate a malfunction.
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 engine OFF. The
system should return to normal within 10 minutes.
If the slip indicator comes on
It may indicate a malfunction in the VSC, TRC or hill start assist control
function. Contact any authorized Lexus dealer or repairer, or another duly
qualified and equipped professional.
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When driving
IS250/220d/200d_EE
CAUTION
Replacing tires
Make sure that all tires are of the specified size, brand, tread pattern and
total load capacity. In addition, make sure that the tires are inflated to the
appropriate tire pressure level.
The ABS, VSC and TRC systems will not function correctly if different
tires are fitted on the vehicle.
Contact any authorized Lexus dealer or repairer, or another duly qualified
and equipped professional, 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 driving assist systems, and may cause the system to malfunction.
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Selecting tire chains
Tire chains can be mounted on 16- and 17-inch tires. They cannot
be mounted on 18-inch tires. Use the correct tire chain size when
mounting the tire chains.
Chain size is regulated for each tire size.
Side chain
(3 mm [0.12 in.] in diameter)
Cross chain
(4 mm [0.16 in.] in diameter)
Regulations on the use of tire chains
Regulations regarding the use of tire chains vary according to
location and type of road. Always check local regulations before
installing chains.
Install the chains on the rear tires.
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 (automatic
transmission) or 1 or R (manual transmission) without setting
the parking brake. The parking brake may freeze up, prevent-
ing it from being released. If necessary, block the wheels to
prevent inadvertent sliding or creeping.
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Guidance
Your vehicle will handle differently when towing a trailer. In order
to avoid accident, death or serious injury, keep the following in
mind when towing:
Checking connections between trailer and lights
Stop the vehicle and check the operation of the connection
between the trailer and lights after driving for a brief period as
well as before setting off.
Practicing driving with a coupled trailer
Get the feel for turning, stopping and reversing with the trailer
coupled by practicing in an area with no or light traffic.
When reversing with a coupled trailer, hold the section of the
steering wheel nearest to you and rotate clockwise to turn the
trailer left or counterclockwise to turn right. Always rotate
gradually to prevent steering error. Have someone guide you
when reversing to lessen the risk of accident.
Increasing vehicle-to-vehicle distance
At a speed of 10 km/h (6 mph), the distance to the vehicle run-
ning ahead of you should be equivalent to or greater than the
combined length of your vehicle and trailer. Avoid sudden brak-
ing that may cause skidding. Otherwise, the vehicle may spin
out of control. This is especially true when driving on wet or
slippery road surfaces.
Sudden acceleration/steering input/cornering
Executing sharp turns when towing may result in the trailer col-
liding with your vehicle. Decelerate well in advance when
approaching turns and take them slowly and carefully to avoid
sudden braking.
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When driving
IS250/220d/200d_EEImportant points regarding turning
The wheels of the trailer will travel closer to the inside of the
curve than the wheels of the vehicle. To make allowance for this,
take the turns wider than you would normally.
Important points regarding stability
Vehicle movement resulting from uneven road surfaces and
strong crosswinds will affect handling. The vehicle may also be
rocked by passing buses or large trucks. Frequently check
behind when moving alongside such vehicles. As soon as such
vehicle movement occurs, immediately start to decelerate
smoothly by slowly applying the brakes. Always steer the vehi-
cle straight ahead while braking.
Passing other vehicles
Consider the total combined length of your vehicle and trailer
and ensure that the vehicle-to-vehicle distance is sufficient
before executing lane changes.
Transmission information
Refrain from driving in 6 (manual transmission) or 4 range in S
mode (automatic transmission) to maintain the effectiveness of
the engine brake and the charge performance of electrical com-
ponents.
If the engine overheats...
Towing a loaded trailer up a long steep incline in temperatures
exceeding 30C (85F) may result in the engine overheating. If
the engine coolant temperature gauge indicates that the engine is
overheating, turn the air conditioning off immediately, leave the
road and stop the vehicle in a safe place. (P. 525)
When parking the vehicle
Always place wheel chocks under the wheels of both the vehicle
and trailer. Firmly set the parking brake and shift the shift lever
to P for automatic transmissions, and 1 or R for manual trans-
missions.