
2344-3. Operating the lights and wipers
IS300h_EE(OM53D56E)
■The Automatic High Beam can be operated when
The power switch is in ON mode.
■Camera sensor detection information
●High beam may not be automatically turned off in the following situations:
• When oncoming vehicles suddenly appear from a curve
• When the vehicle is cut in front of by another vehicle
• When oncoming or preceding vehicles are hidden from sight due to repeatedcurves, road dividers or roadside trees
●High beam may be turned off if an oncomi ng vehicle that is using fog lights without
using the headlights is detected.
●House lights, street lights, red traffic sign als, and illuminated billboards or signs may
cause the high beam to turn off.
●The following factors may affect the amount of time taken to turn high beam on or off:
• The brightness of headlights, fog lights, and tail lights of oncoming and preceding
vehicles
• The movement and direction of oncoming and preceding vehicles
• When an oncoming or preceding vehicle only has operational lights on one side
• When an oncoming or preceding vehicle is a two-wheeled vehicle
• The condition of the road (gradient, curve, condition of the road surface etc.)
• The number of passengers and amount of luggage
●High beam may be turned on or off when unexpected by the driver.
●Small vehicles, such as bicycles, may not be detected.
●In the situations below, the system may not be able to correctly detect the surrounding
brightness levels, and may flash or expose nearby pedestrians to the high beam. There-
fore, you should consider turning the high be ams on or off manually rather than relying
on the Automatic High Beam system.
• In bad weather (rain, snow, fog, sandstorms etc.)
• The windshield is obscured by fog, mist, ice, dirt etc.
• The windshield is cracked or damaged.
• The camera sensor is deformed or dirty.
• Surrounding brightness levels are equal to th ose of headlights, tail lights or fog lights.
• Vehicles ahead have headlights or tail lights that are either switched off, dirty, chang-
ing color, or have improperly adjusted aim.
• When driving through an area of intermittently changing brightness and darkness.
• When frequently and repeatedly driving ascending/descending roads, or roads with
rough, bumpy or uneven surfaces (such as stone-paved roads, gravel tracks etc.).
• When frequently and repeatedly taking curves or driving on a winding road.
• There is a highly reflective object ahead of the vehicle, such as a sign or a mirror.
• The vehicle’s headlights are damaged or dirty.
• The vehicle is listing or titling, due to a flat tire, a trailer being towed etc.
• The driver believes that the high beam may be causing problems or distress to other drivers or pedestrians nearby.
• The vehicle is used in a territory in which vehicles travel on the opposite side of the
road of the country for which the vehicle is approved, for example using a vehicle
designed for right-hand traffic in a left-hand traffic territory, or vice versa.

2734-5. Using the driving support systems
4
Driving
IS300h_EE(OM53D56E)
■Temporary cancelation of the LDA system functions
If any of the following occurs, the LDA system functions will be temporarily canceled. The
functions will resume after the necessary operating conditions have returned.
●The turn signal lever is operated.
●The vehicle speed deviates from the operating range of the LDA system functions.
●When the lane lines cannot be recognized while driving.
●When the lane departure warning sounds.
The lane departure warning function will not operate again for a several seconds after it
has been activated, even if the vehicle leaves the lane again.
■The lane departure warning
Depending on the audio system sound level or air conditioning fan noise while the audio
system or air conditioning system is in use, it may be difficult to hear the warning sound.
■After the vehicle has been parked in the sun
The LDA system may not be available and a warning message ( →P. 533) will be dis-
played for a while after driving has started. When the temperature in the cabin decreases
and the temperature around the camera sensor ( →P. 270) becomes suitable for its
operation, the functions will begin to operate.
■If there are lane markers on only one side of the vehicle
The lane departure warning will not operate fo r the side on which lane markers could not
be recognized.
■Conditions in which the function may not operate correctly
In the following situations, the camera sensor may be unable to recognize lane markers
causing the lane departure warning function to operate incorrectly. However, this does
not indicate a malfunction.
●When driving through an area with no lane markers, such as a tollbooth, a crossing or
before a ticket checkpoint
●When driving on a sharp curve
●When lane markers are extremely narrow or extremely wide
●When the vehicle leans to one side an unusual amount due to a heavy load or improper
tire inflation pressure
●When the following distance between your vehicle and the vehicle ahead is extremely
short
●When the lane markers are yellow (These may be more difficult for the system to rec-
ognize compared to white markers.)
●When the lane markers are broken, Botts’ dots (raised pavement markers) or stones
●When the lane markers are on a curb etc.
●When lane markers are obscured or partially obscured by sand, dirt, etc.
●When there are shadows on the road running parallel with lane markers, or if a shadow
covers the lane markers
●When driving on a particularly brig ht road surface, such as concrete
●When driving on a road surface that is bright due to reflected light
●When driving in a location where the light level changes rapidly, such as the entrance to
or exit from a tunnel

2744-5. Using the driving support systems
IS300h_EE(OM53D56E)
●When sunlight or the headlights of oncoming vehicles are shining directly into the cam-
era lens
●When driving on roads that are branching or merging
●When driving on a road surface that is wet due 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 wi nding roads or roads that are uneven
●When driving on rough or unpaved roads
■When changing the tires
Depending on the tires used, such as snow ti res, etc., sufficient performance may not be
maintainable.
■Warning messages for the LDA system
Warning messages are used to indicate a system malfunction or to inform the driver of
the need for caution while driving. ( →P. 5 3 3 )
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 driving 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, dirt, 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

2904-5. Using the driving support systems
IS300h_EE(OM53D56E)
■If you notice any symptoms
If you notice any of the following symptoms, refer to the likely cause and the
solution, and re-check.
If the symptom is not resolved by the solution, have the vehicle inspected by
any authorized Lexus dealer or repairer, or another duly qualified and
equipped professional.
Things you should know
Likely causeSolution
‰ The image is difficult to see
• The vehicle is in a dark area
• The temperature around the lens is
either high or low
• The outside temperature is low
• There are water droplets on the cam- era
• It is raining or humid
• Foreign matter (mud etc.) is adhering to the camera
• Sunlight or headlights are shining directly into the camera
• The vehicle is under fluorescent lights,
sodium lights, mercury lights etc.
If this happens due to these causes, it
does not indicate a malfunction.
Back up while visually checking the vehi-
cle’s surroundings. (Use the monitor
again once conditions have been
improved.)
To adjust the image on the rear view mon-
itor system screen. ( →P. 3 4 2 )
‰ The image is blurry
Dirt or foreign matter (such as water
droplets, snow, mud etc.) is adhering to
the camera.Flush the camera with a large quantity of
water and wipe the camera lens clean
with a soft and wet cloth.
‰The image is out of alignment
The camera or surrounding area has
received a strong impact.Have the vehicle inspected by any autho-
rized Lexus dealer or repairer, or another
duly qualified and equipped professional.
‰The fixed guide lines are very far out of alignment
• The vehicle is tilted (there is a heavy
load on the vehicle, tire pressure is low
due to a tire puncture, etc.)
• The vehicle is used on an incline.If this happens due to these causes, it
does not indicate a malfunction. Back up
while visually checking the vehicle’s sur-
roundings.
The camera position is out of alignment.
Have the vehicle inspected by any autho-
rized Lexus dealer or repairer, or another
duly qualified and equipped professional.

2914-5. Using the driving support systems
4
Driving
IS300h_EE(OM53D56E)
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 displayed 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 condition, 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 parking 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
• 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 direct 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 dist ances between objects and pedestrians that
appear in the image displayed on the screen will differ from the actual distances.
( → P. 2 8 5 )

3014-5. Using the driving support systems
4
Driving
IS300h_EE(OM53D56E)
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 vehi cle’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
■TRC may not operate effectively when
Directional control and power may not be achievable while driving on slippery road
surfaces, even if the TRC 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 control. Hill-start assist control may not operate
effectively on steep inclines and roads covered with ice.
●Unlike the parking brake, hill-start assist co ntrol 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 dr ive carefully. Reckless driving may cause an
accident. Exercise particular care when the indicator light flashes.
■When the TRC/VSC systems are turned off
Be especially careful and drive at a speed appropriate to the road conditions. As these
are the systems to help ensure vehicle stability and driving force, do not turn the TRC/
VSC systems off unless necessary.
■Replacing tires
Make sure that all tires are of the specif ied 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, TRC and VSC systems will not function correctly if different tires are installed
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 the suspension
Using tires with any kind of problem or modi fying the suspension will affect the driving
assist systems, and may cause a system to malfunction.

3214-6. Driving tips
4
Driving
IS300h_EE(OM53D56E)
■Air conditioning
Use the air conditioning only when necessary. Doing so can help reduce
excessive gasoline consumption.
In summer: When the ambient temperature is high, use the recirculated air
mode. Doing so will help to reduce the burden on the air conditioning system
and reduce fuel consumption as well.
In winter: Because the gasoline engine will not automatically cut out until it
and the interior of the vehicle are warm, it will consume fuel. 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 infla-
tion pressure can cause poor fuel economy.
Also, as snow tires can cause large amounts of friction, their use on dry roads
can lead to poor fuel economy. Use tires that are appropriate for the season.
■Luggage
Carrying heavy luggage can lead to poor fuel economy. Avoid carrying
unnecessary luggage. Installing a large roof rack can also cause poor fuel
economy.
■Warming up before driving
Since the gasoline engine starts up and cuts out automatically when cold,
warming up the engine is unnecessary. Moreover, frequently driving short dis-
tances will cause the engine to repeatedly warm up, which can lead to excess
fuel consumption.

3224-6. Driving tips
IS300h_EE(OM53D56E)
●Use fluids that are appropriate to the prevailing outside temperatures. •Engine oil
• Engine/power control unit coolant
•Washer fluid
●Have a service technician inspect the condition of the 12-volt 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