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4-5. Using the driving support systems
●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 LKA
Warning messages are used to indicate a system malfunction or to inform the driver
of the need for caution while driving. (→P. 7 2 4 , 7 3 5 )
CAUTION
■Before using the LKA system
Do not rely solely on the LKA system. The LKA system does not drive the vehicle
automatically, 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 surround-
ings, for operating the steering wheel to correct the driving line, and for driving
safely.
Inappropriate or negligent driving could lead to an accident.
■To avoid operating the LKA by mistake
Switch the LKA off using the “LKA” switch when not in use.
■Situations unsuitable for LKA
Do not use LKA in any of the following situations.
Otherwise, the system may not function correctly and could result in an accident.
●When driving with snow tires, tire chains, a spare tire, or similar equipment
●When the tires have been excessively worn, or when the tire inflation pressure is
low.
●When there are objects or structures along the roadside that might be misinter-
preted as lane markers (such as guardrails, curb, reflector posts, etc.)
●When driving on snowy roads
●When pavement lane markers are difficult to see due to rain, snow, fog, 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 slippery roads, such as those covered with rain, ice or snow
●When driving in a lane other than the driving or passing lanes on a freeway or
highway
●When driving on a road with lane closures due to maintenance, or when driving
in a temporary lane
●When emergency towing
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2954-5. Using the driving support systems
4
Driving
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 recommended tire
inflation 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 modifying the suspension will affect the
driving assist systems, and may cause a system to malfunction.
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4-6. Driving tips
■Air conditioning
Use the air conditioning only when necessary. Doing so can help con-
trol excessive gasoline consumption.
In summer: In high temperatures, use the recirculated air mode. Doing
so will help to reduce the burden on the air conditioner and reduce fuel
consumption as well.
In winter: Because the gasoline engine will not automatically cut out
until the gasoline engine and the interior of the vehicle are warm, it will
consume fuel. Also, fuel consumption can be improved by avoiding
overuse of the heater.
■Checking tire inflation pressure
Make sure to check the tire inflation pressure frequently. Improper tire
inflation pressure can cause poor fuel consumption.
Also, as snow tires can cause large amounts of friction, their use on dry
roads can lead to poor fuel consumption. Use a tire that is appropriate
for the season.
■Luggage
Carrying heavy luggage can lead to poor fuel consumption. Avoid car-
rying unnecessary luggage. Installing a large roof rack can also cause
poor fuel consumption.
■Warming up before driving
Since the gasoline engine starts up and cuts out automatically when
cold, warming up the engine is unnecessary. Moreover, frequently driv-
ing short distances will cause the engine to repeatedly warm up, which
can lead to poor fuel consumption.
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3234-6. Driving tips
4
Driving
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 vehicle 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.
●Do not use LKA (Lane-Keeping Assist) system.
■Driving with tire chains
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, abrupt steering, as well as sudden braking and shift-
ing operation to engine braking.
●Slow down sufficiently before entering a curve to ensure that vehicle control is
maintained.
●Do not use LKA (Lane-Keeping Assist) system.
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4-6. Driving tips
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
The tire pressure warning valves and transmitters may not function correctly when
tire chains are fitted.
■When standing the windshield wipers up
Raise the wipers in line with the windshield. (→P. 3 2 2 )
Failure to do so may result in damage to the wipers and/or the hood.
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3295-1. Remote Touch screen
5
Interior features
CAUTION
■When using the Remote Touch
●Do not allow fingers, fingernails or hair to become caught in the Remote Touch as
this may cause an injury.
●Be careful when selecting the Remote Touch in extreme temperatures as it may
become very hot or cold due to the temperature inside the vehicle.
NOTICE
■To prevent damage to the Remote Touch
●Do not allow the Remote Touch to come into contact with food, liquid, stickers or
lit cigarettes as doing so may cause it to change color, emit a strange odor or stop
functioning.
●Do not subject the Remote Touch to excessive pressure or strong impact as the
knob may bend or break off.
●Do not allow coins, contact lenses or other such items to become caught in the
Remote Touch as this may cause it to stop functioning.
●Items of clothing may rip if they become caught on the Remote Touch knob.
●If your hand or any object is on the Remote Touch knob when the power switch is
turned to ACCESSORY mode, the Remote Touch knob may not operate prop-
erly.
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5-3. Using the audio system
CAUTION
■While driving
Do not connect an USB memory or operate the controls.
NOTICE
■To prevent damage to the USB memory or its terminal
●Do not leave USB memory in the vehicle. The temperature inside of the vehicle
may become high, resulting in damage to the USB memory.
●Do not push down on or apply unnecessary pressure to the USB memory while it
is connected.
●Do not insert foreign objects into the port.
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5-3. Using the audio system
CAUTION
■While driving
Do not connect an iPod or operate the controls.
NOTICE
■To prevent damage to the iPod or its terminal
●Do not leave the iPod in the vehicle. The temperature inside the vehicle may
become high, resulting in damage to the iPod.
●Do not push down on or apply unnecessary pressure to the iPod while it is con-
nected.
●Do not insert foreign objects into the port.
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