snow chains Lexus IS250 2014 Do-it-yourself service precautions / LEXUS 2014 IS250,IS350 OWNERS MANUAL (OM53758U)

2124-5. Using the driving support systems
IS350/250_U (OM53758U)
●When driving on roads that are branching or merging
●When driving on a road surface that is wet du e to rain, previous rainfall, standing water,
etc.
●When the vehicle experiences strong up-and -down motion such as when driving on an
extremely rough road or on a seam in the pavement
●When headlight brightness at nighttime is reduced due to dirt on the lenses, or when
the headlights are misaligned
●When driving on winding roads or roads that are uneven
●When driving on rough or unpaved roads
■When changing the tires
Depending on the tires used, sufficient performance may not be maintainable.
■Warning messages for the LDA system
Warning messages are used to indicate a syst em malfunction or to inform the driver of
the need for caution while driving. ( P. 4 6 5 )
CAUTION
■Before using the LDA system
Do not rely solely on the LDA system. The LDA system does not drive the vehicle auto-
matically, nor does it reduce the amount of care you need to take. As such, the driver
must always assume full responsibility for understanding his/her surroundings, for
operating the steering wheel to correct the driving line, and for driving safely.
Inappropriate or negligent drivin g could lead to an accident.
■To avoid operating the LDA by mistake
Switch the LDA system off using the LDA switch when not in use.
■Situations unsuitable for LDA system
Do not use the LDA system in any of the following situations.
Otherwise, the system may not function correctly and could result in an accident.
●When driving with tire chains, a spare tire, or similar equipment
●When there are objects or structures along the roadside that might be misinterpreted
as lane markers (such as guardrails, a curb, reflector posts, etc.)
●When driving on snowy roads
●When pavement lane markers are difficult to see due to rain, snow, fog, sand dust, etc.
●When there are visible lines on the pavement from road repairs, or if the remains of
old lane markers are still visible on the road
●When driving on a road with lane closures due to maintenance, or when driving in a
temporary lane

2294-5. Using the driving support systems
4
Driving
IS350/250_U (OM53758U)
CAUTION
■When using the rear view monitor system
The rear view monitor system is a supplemental device intended to assist the driver
when backing up. When backing up, be sure to check visually behind and all around
the vehicle before proceeding.
Observe the following precautions to avoid an accident that could result in death or
serious injuries.
●Never depend on the rear view monitor system 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.
●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 rear view monitor 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 rear view monitor system in the following cases:
• On icy or slick road surfaces, or in snow
• When using tire chains or the compact spare tire
• When the trunk lid 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 fixed guide lines displayed on the
screen may change.
●The camera uses a special lens. The distances between objects and pedestrians that
appear in the image displayed on the screen will differ from the actual distances.
(  P. 2 2 4 )

2394-5. Using the driving support systems
4
Driving
IS350/250_U (OM53758U)
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 appropriate to the road conditions. As these
are the systems to ensure vehicle stability 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.

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IS350/250_U (OM53758U)4-6. Driving tips
●Use fluids that are appropriate to the prevailing outside temperatures.
•Engine oil
• Engine coolant
• Washer fluid
●Have a service technician inspect the condition of the battery.
●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 brand, and that chains match the size
of the tires.
*: Tire chains cannot be mounted on the 18-inch tires.
Perform the following according to the driving conditions:
●Do not try to forcibly open a window or move a wiper that is frozen. Pour
warm water over the frozen area to melt the ice. Wipe away the water imme-
diately 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.
●Check for and remove any excess ice or snow that may have accumulated on
the exterior lights, vehicle’s roof, chassis, around the tires or on the brakes.
●Remove any snow or mud from the bottom of your shoes before getting in the
vehicle.
Accelerate the vehicle slowly, keep a safe distance between you and the vehicle
ahead, and drive at a reduced speed suitable to road conditions.
Winter driving tips
Carry out the necessary preparations and inspections before driving the vehi-
cle in winter. Always drive the vehicle in a manner appropriate to the prevail-
ing weather conditions.
Preparation for winter
Before driving the vehicle
When driving the vehicle

2554-6. Driving tips
4
Driving
IS350/250_U (OM53758U)
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
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Regulations on the use of tire chains

2564-6. Driving tips
IS350/250_U (OM53758U)
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.

4157-3. Do-it-yourself maintenance
7
Maintenance and care
IS350/250_U (OM53758U)
■Low profile tires (except 16-inch tires)
Generally, low profile tires will wear more rapidly and tire grip performance will be
reduced on snowy and/or icy roads when compared to standard tires. Be sure to use
snow tires or tire chains
* on snowy and/or icy roads and drive carefully at a speed appro-
priate for road and weather conditions.
*: Tire chains cannot be mounted on the 18-inc h tires. Snow tires should be used instead.
■Maximum load of tire
Check that the maximum load of the replacem ent tire is greater than 1 /2 of the Gross
Axle Weight Ratings (GAWR) of either the front axle or the rear axle, whichever is
greater.
■Tire types
●Summer tires
Summer tires are high-speed performance tires best suited to highway driving under
dry conditions. Since summer tires do not have the same traction performance as
snow tires, summer tires are inadequate for driving on snow-covered or icy roads. For
driving on snow-covered roads or icy roads, the use of snow tires is recommended.
When installing snow tires, be sure to replace all four tires.
●All season tires
All season tires are designed to provide better traction in snow and to be adequate for
driving in most winter condit ions as well as for use year-round. All season tires, how-
ever, do not have adequate traction performance compared with snow tires in heavy
or loose snow. Also, all season tires fall short in acceleration and handling perfor-
mance compared with summer tires in highway driving.
●Snow tires
For driving on snow-covered roads or icy roads, we recommend using snow tires. If
you need snow tires, select tires of the same size, construction and load capacity as the
originally installed tires. Since your vehicle has radial tires as original equipment, make
sure your snow tires also have radial cons truction. Do not install studded tires without
first checking local regulations for possible re strictions. Snow tires should be installed
on all wheels. ( P. 2 5 4 )
For the GAWR, see the Certification Label. For
the maximum load of the tire, see the load limit
at maximum cold tire inflation pressure men-
tioned on the sidewall of the tire. (
P. 5 1 3 )

4167-3. Do-it-yourself maintenance
IS350/250_U (OM53758U)
■If the tread on snow tires wears down below 0.16 in. (4 mm)
The effectiveness of the tires as snow tires is lost.
■Situations in which the tire pressure warning system may not operate properly
●In the following cases, the tire pressure warning system may not operate properly.
• If non-genuine Lexus wheels are used.
• A tire has been replaced with a tire that is not an OE (Original Equipment) tire.
• A tire has been replaced with a tire that is not of the specified size.
• Tire chains etc. are equipped.
• Lock nuts are equipped.
• An auxiliary-supported run-flat tire is equipped.
• If a window tint that affects the radio wave signals is installed.
• If there is a lot of snow or ice on the vehicle, particularly around the wheels or wheel housings.
• If the tire inflation pressure is extremely higher than the specified level.
• If tires not equipped with tire pressure warning valves and transmitters are used.
• If the ID code on the tire pressure warning valves and transmitters is not registered in the tire pressure warning computer.
●Performance may be affected in the following situations.
• Near a TV tower, electric power plant, gas station, radio station, large display, air-
port or other facility th at generates strong radio waves or electrical noise
• When carrying a portable radio, cellular phone, cordless phone or other wireless
communication device
If tire position information is not correctl y displayed due to the radio wave conditions,
the display may be corrected by driving and changing the radio wave conditions.
●When the vehicle is parked, the time taken for the warning to start or go off could be
extended.
●When tire inflation pressure declines rapidly for example when a tire has burst, the
warning may not function.
■The initialization operation
●Make sure to carry out initialization af ter adjusting the tire inflation pressure.
Also, make sure the tires are cold before carry ing out initialization or tire inflation pres-
sure adjustment.
●If you have accidentally turned the engine swit ch off during initialization, it is not neces-
sary to press the reset switch again as init ialization will restart automatically when the
engine switch has been turned to IG NITION ON mode for the next time.
●If you accidentally press the reset switch when initialization is not necessary, adjust the
tire inflation pressure to the specified level when the tires are co ld, and conduct initial-
ization again.

4838-2. Steps to take in an emergency
8
When trouble arises
IS350/250_U (OM53758U)
■The compact spare tire
●The compact spare tire is identified by the label “TEMPORARY USE ONLY” on the
tire sidewall.
Use the compact spare tire temporarily, and only in an emergency.
●Make sure to check the tire inflation pressure of the compact spare tire.
(  P. 5 0 7 )
■When using the compact spare tire
As the compact spare tire is not equipped wi th a tire pressure warning valve and trans-
mitter, low inflation pressure of the spare ti re will not be indicated by the tire pressure
warning system. Also, if you replace the compact spare tire after the tire pressure warn-
ing light comes on, th e light remains on.
■When the compact spare tire is equipped
The vehicle becomes lower when driving with the compact spare tire compared to when
driving with standard tires.
■If you have a flat rear tire on a road covered with snow or ice (vehicles with front and
rear tires of the same size)
Install the compact spare tire on one of the front wheels of the vehicle. Perform the fol-
lowing steps and fit tire chains to the rear tires:
Replace a front tire with the compact spare tire.
Replace the flat rear tire with the tire removed from the front of the vehicle.
Fit tire chains to the rear tires.
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568Alphabetical index
IS350/250_U (OM53758U)
Tachometer .................................................81
Tail lights..................................................... 173Light switch .............................................173
Replacing light bulbs ........................ 442
Talk switch
*..............................................321
Telephone switches
*............................321
Theft deterrent system Alarm............................................................. 71
Engine immobilizer system..............69
Luggage security system .................. 110
Theft prevention labels ....................... 73
Tire inflation pressure ......................... 420 Maintenance data ............................. 507
Tire inflation pressure display function ..................................................412
Warning light .......................................457
Tire information ...................................... 513 Glossary ................................................ 520
Size ............................................................. 516
Tire identification number............... 515
Uniform Tire Quality Grading................................................ 518 Tire pressure warning system ........... 412
Function .................................................... 412
Initializing ................................................. 412
Installing tire pressure warning valves and transmitters.................. 412
Registering ID codes ......................... 414
Tire pressure warning reset switch ..................................................... 413
Warning light ....................................... 457
Tires ...............................................................411 Chains ..................................................... 255
Checking ...................................................411
If you have a flat tire .......................... 475
Inflation pressure................................ 507
Information..............................................513
Replacing ............................................... 475
Rotating tires ............................................411
Size ........................................................... 507
Snow tires .............................................. 256
Spare tire................................................ 475
Tire inflation pressure display function.................................................. 412
Tire pressure warning system ....... 412
Warning light ....................................... 457
T