2015 Lexus IS250 wheel

2354-5. Using the driving support systems
4
Driving
IS350/250_U (OM53C50U)
CAUTION
■When using the Lexus parking assist monitor system
The parking assist monitor is a supplemental device intended to assist the driver when
backing up. When backing up, be sure to chec k visually behind and all around the vehi-
cle before proceeding.
Observe the following precautions to avoid an accident that could result in death or
serious injuries.
●Never depend on the parking assist monitor entirely when backing up. The image
and the position of the guide lines displaye d on the screen may differ from the actual
state.
Use caution, just as you would when backing up any vehicle.
●Be sure to back up slowly, depressing the brake pedal to control vehicle speed.
●If you seem likely to hit nearby vehicles, obstacles, people or mount the shoulder,
depress the brake pedal to stop the vehicle.
●The instructions given are only guidelines.
When and how much to turn the steering wheel will vary according to traffic condi-
tions, road surface conditions, vehicle condit ion, etc. when parking. It is necessary to
be fully aware of this before using the parking assist system.
●When parking, be sure to check that the par king space will accommodate your vehi-
cle before maneuvering into it.
●Do not use the parking assist monitor in the following cases:
• On icy or slick road surfaces, or in snow
• When using tire chains or emergency tires
• When the trunk is not closed completely
• On roads that are not flat or straight, such as curves or slopes.
●In low temperatures, the screen may darken or the image may become faint. The
image could distort when the vehicle is moving, or you may become unable to see the
image on the screen. Be sure to check dire ct visually and with the mirrors all around
the vehicle before proceeding.
●If the tire sizes are changed, the position of the guide lines displayed on the screen
may change.
●The camera uses a special lens. The dist ances between objects and pedestrians that
appear in the image displayed on the screen will differ from the actual distances.
(  P. 2 2 9 )
●Estimated course line display mode: If the st eering wheel is straight and the vehicle
width guide lines and the estimated course li nes are not in alignment, have the vehicle
inspected by your Lexus dealer.

2404-5. Using the driving support systems
IS350/250_U (OM53C50U)
◆ABS (Anti-lock Brake System)
Helps to prevent wheel lock when the brakes are applied suddenly, or if the
brakes are applied while drivin g 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
◆Enhanced VSC (Enhanced Vehicle Stability Control)
Provides cooperative control of the ABS, TRAC, VSC and EPS.
Helps to maintain directional stability when swerving on slippery road sur-
faces by controlling steering performance.
◆TRAC (Traction Control)
Helps to maintain drive power and prevent the drive wheels from spinning
when starting the vehicle or accelerating on slippery roads
◆Hill-start assist control
Prevents the vehicle from rolling backward when starting on an incline or slip-
pery slope
◆VGRS (Variable Gear Ratio Steering) (if equipped)
Adjusts the front wheel turning angle in accordance with the vehicle speed
and steering wheel movement
Driving assist systems
To help enhance driving safety and performance, the following systems oper-
ate 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.

2414-5. Using the driving support systems
4
Driving
IS350/250_U (OM53C50U)
◆EPS (Electric Power Steering)
Employs an electric motor to reduce the amount of effort needed to turn the
steering wheel
◆Adaptive Variable Suspension system (if equipped)
By independently controlling the dampin g force of the shock absorbers for
each of the 4 wheels according to the road and driving conditions, this system
combines riding comfort with superior steering stability, and helps good vehi-
cle posture. ( P. 2 3 8 )
◆VDIM (Vehicle Dynamics Integrated Management)
Provides integrated control of the ABS, brake assist, TRAC, VSC, hill-start
assist control, EPS and VGRS (if equipped) systems
Helps to maintain vehicle stability when swerving on slippery road surfaces by
controlling the brakes, engine output, steering assist, and if equipped with
VGRS, steering ratio
◆PCS (Pre-Collision System) (if equipped)
 P. 2 4 6
◆BSM (Blind Spot Monitor) (if equipped)
P. 2 5 2
The slip indicator light will flash while
the TRAC/VSC systems are operating.
When the TRAC/VSC systems are operating

2434-5. Using the driving support systems
4
Driving
IS350/250_U (OM53C50U)
■VGRS is disabled when
VGRS may stop operating in the following situations.
In this event, the steering wheel may move from its straight forward position, but it will
return when the system restarts.
●When the steering wheel is operated for an extended period of time while the vehicle is
stopped or is moving very slowly
●When the steering wheel has been held fully to the left or right
The center position of the steering wheel may change when VGRS is disabled. However,
the position will return to normal after VGRS is reactivated.
■When the battery is disconnected
The steering wheel may move fr om its straight forward position, but this will be corrected
automatically when driving.
■Sounds and vibrations caused by the ABS, brake assist, VSC, TRAC, hill-start assist
control and VGRS systems
●A sound may be heard from the engine compartment when 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 sys-
tems.
●Any of the following condit ions 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 slig htly after the ABS is activated.
• The brake pedal may move down s lightly after the ABS is activated.
■EPS and VGRS operation sound
When the steering wheel is operated, a motor sound may be heard. This does not indi-
cate a malfunction.
■Reactivation of the TRAC/VSC systems
Even after the TRAC/VSC systems have been turned off, turning the engine off and then
on again will automatically reactivate the TRAC/VSC systems.
■Reactivation of the TRAC system linked to vehicle speed
When only the TRAC system is turned off, the TRAC system will turn on when vehicle
speed increases. However, when both TRAC /VSC systems are turned off, the systems
will not turn on even when vehicle speed increases.

2444-5. Using the driving support systems
IS350/250_U (OM53C50U)
■Reduced effectiveness of the EPS system
The effectiveness of the EPS system 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 of f. The EPS system should return to normal
within 10 minutes.
■Operating conditions of hill-start assist control
When the following four conditions are met, the hill-start assist control will operate:
●The shift lever is in a position other than P or N (when starting off forward/backward on
an upward incline).
●The vehicle is stopped.
●The accelerator pedal is not depressed.
●The parking brake is not engaged.
■Automatic system cancelation of hill-start assist control
The hill-start assist control will turn off in any of the following situations:
●The shift lever is moved to P or N.
●The accelerator pedal is depressed.
●The parking brake is engaged.
●Approximately 2 seconds elapse after the brake pedal is released.

2454-5. Using the driving support systems
4
Driving
IS350/250_U (OM53C50U)
CAUTION
■The ABS does not operate effectively when
●The limits of tire gripping performance have been exceeded (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 is operating may exceed that of normal conditions
The ABS is not designed to shorten the vehicle’s stopping distance. Always maintain a
safe distance from the vehicle in front of you, especially 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 uneven surfaces
■TRAC may not operate effectively when
Directional control and power may not be achievable while drivin g on slippery road
surfaces, even if the TRAC system is operating.
Drive the vehicle carefully in conditions where stability and power may be lost.
■Hill- start assist control does not operate effectively when
●Do not overly rely on hill-start assist contro l. Hill-start assist control may not operate
effectively on steep inclines and roads covered with ice.
●Unlike the parking brake, hill-start assist control is not intended to hold the vehicle
stationary for an extended period of time. Do not attempt to use hill-start assist con-
trol to hold the vehicle on an incline, as doing so may lead to an accident.
■When the VSC is activated
The slip indicator light flashes. Always drive carefully. Reckless driving may cause an
accident. Exercise particular care when the indicator light flashes.
■When the TRAC/VSC systems are turned off
Be especially careful and drive at a speed ap propriate to the road conditions. As these
are the systems to help ensure vehicle st ability and driving force, do not turn the
TRAC/VSC systems off unless necessary.
■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 recommended tire infla-
tion pressure level.
The ABS, TRAC and VSC systems will not function correctly if different tires are
installed on the vehicle.
Contact your Lexus dealer for further information when replacing tires or wheels.
■Handling of tires and the suspension
Using tires with any kind of problem or modi fying the suspension will affect the driving
assist systems, and may caus e a system to malfunction.

2614-6. Driving tips
4
Driving
IS350/250_U (OM53C50U)
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 inadvertent sliding or creeping.
Except vehicles with 18-inch tires
Use the correct tire chain size when mounting the tire chains.
Chain size is regulated for each tire size.
Side chain
(0.12 in. [3 mm] in diameter)
Cross chain
(0.16 in. [4 mm] in diameter)
Vehicles with 18-inch tires
Tire chains cannot be mounted.
Snow tires should be used instead.
Regulations regarding the use of tire chains vary depending on location and type
of road. Always check local regulations before installing chains.
■Tire chain installation
Observe the following precautions wh en installing and removing chains:
●Install and remove tire chains in a safe location.
●Install tire chains on the rear tires. Do not install tire chains on the front tires.
●Install tire chains on rear tires as tightly as possible. Retighten chains after driving 1 /4
 1 /2 mile (0.5  1.0 km).
●Install tire chains following the instru ctions provided with the tire chains.
When parking the vehicle
Selecting tire chains
1
2
Regulations on the use of tire chains

2624-6. Driving tips
IS350/250_U (OM53C50U)
CAUTION
■Driving with snow tires
Observe the following precautions to reduce the risk of accidents.
Failure to do so may result in a loss of ve hicle control and cause death or serious injury.
●Use tires of the specified size.
●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.
■Driving with tire chains (except vehicles with 18-inch tires)
Observe the following precautions to reduce the risk of accidents.
Failure to do so may result in the vehicle being unable to be driven safely, and may
cause death or serious injury.
●Do not drive in excess of the speed limit specified for the tire chains being used, or 30
mph (50 km/h), whichever is lower.
●Avoid driving on bumpy road surfaces or over potholes.
●Avoid sudden acceleration, ab rupt steering, sudden braking and shifting operations
that cause sudden engine braking.
●Slow down sufficiently before entering a cu rve to ensure that vehicle control is main-
tained.
●Do not use LDA (Lane Departure Alert) system.
NOTICE
■Repairing or replacing snow tires
Request repairs or replacement of snow tires from Lexus dealers or legitimate tire
retailers.
This is because the removal and attachment of snow tires affects the operation of the
tire pressure warning valves and transmitters.
■Fitting tire chains (except vehicles with 18-inch tires)
The tire pressure warning valves and transmitters may not function correctly when tire
chains are fitted.