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CAUTION
■TRAC may not operate effectively when
Directional control and power may not be achievable while driving on slippery road
surfaces, even if the TRAC system is operating.
Do not drive the vehicle in conditions where stability and power may be lost.
■If hill-start assist control does not operate effectively
(vehicles with an automatic transmission)
Do not overly rely on the hill-start assist control. The hill-start assist control may not
operate effectively on steep inclines and roads covered in ice.
■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 TRAC and VSC are off
Be especially careful and drive at a speed appropriate to the road conditions. As
these are systems to ensure vehicle stability and driving force, do not turn off TRAC
and VSC 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
pressure level.
The ABS, VSC and TRAC systems will not function correctly if different tires are fit-
ted on the vehicle.
Contact your Lexus dealer 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 driv-
ing assist systems, and may cause the system to malfunction.
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When driving
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2-5. Driving information
Cargo and luggage
Capacity and distributionCargo capacity depends on the total weight of the occupants.
(Cargo capacity) = (Total load capacity) — (Total weight of occupants)
Steps for Determining Correct Load Limit
(1) Locate the statement “The combined weight of occupants and cargo should never exceed XXX kg or XXX lbs.” on your vehicle’s placard.
(2) Determine the combined weight of the driver and passengers that will be riding in your vehicle.
(3)Subtract the combined weight of the driver and passengers from XXX kg or XXX lbs.
(4) The resulting figure equals the available amount of cargo and luggage load capacity.
For example, if the “XXX” amount equals 1400 lbs. and there will be
five 150 lb passengers in your vehicle, the amount of available cargo
and luggage load capacity is 650 lbs. (1400 − 750 (5 × 150) = 650
lbs.)
(5)Determine the combined weight of luggage and cargo being loaded on the vehicle. That weight may not safely exceed the available cargo
and luggage load capacity calculated in Step 4.
Take notice of the following information about storage precautions, cargo
capacity and load.
●Stow cargo and luggage in the trunk whenever possible. Be sure
all items are secured in place.
● Be careful to keep the vehicle level. Placing the weight as far for-
ward as possible helps maintain vehicle balance.
● For better fuel economy, do not carry unnecessary weight.
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When driving
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.
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2-5. Driving information
IS350/250_U
Selecting tire chainsTire 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
(0.12 in. [3 mm] in diameter)
Cross chain
(0.16 in. [4 mm] 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.
● Retighten the chains after driving 1 /4 1 /2 mile (0.5 1.0 km).
■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 transmis-
sion) or 1 or R (manual transmission) without setting the parking
brake. The parking brake may freeze up, preventing it from being
released. If necessary, block the wheels to prevent inadvertent slid-
ing or creeping.
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When driving
IS350/250_U
■Snow chain installation
Observe the following precautions when installing and removing chains.
●Install and remove tire chains in a safe location.
●Install tire chains on the rear tires only. Do not install tire chains on front tires.
●Install the 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 instructions provided in the accompanying
instructions.
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.
■Driving with tire chains
Observe the following precautions to reduce the risk of accidents.
Failing 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 turns and braking, as use of chains may adversely affect vehicle
handling.
●Slow down sufficiently before entering a curve to ensure that vehicle control is
maintained.
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NOTICE
■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.
■Fitting tire chains
The tire pressure warning system may not function correctly when tire chains are fit-
ted.
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When driving
IS350/250_U
Dinghy towing (vehicles with a manual transmission)
Towing your vehicle with 4 wheels on the groundTo prevent damage to your vehicle, perform the following procedures
before towing. Shift the shift lever to neutral.
Switch to ACCESSORY mode. ( →P. 1 3 6 )
Ensure that the audio system and other powered devices have been
turned off.
Release the parking brake.
After towing, leave the engine in idle for at least 3 minutes before driv-
ing the vehicle.
■Necessary equipment and accessories
Specialized equipment and accessories are required for dinghy towing. Contact
the service branch of the motor home manufacturer regarding recommended
equipment.
Your vehicle can be dinghy towed in a forward direction (with 4 wheels on
the ground) behind a motor home.
STEP1
STEP2
STEP3
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NOTICE
■Dinghy towing direction
■To prevent the steering from locking
Ensure the “ENGINE START STOP” switch is in ACCESSORY mode.
Do not tow the vehicle backwards.
Doing so may cause serious damage.