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2474-1. Before driving
4
Driving
GS450h_300h_OM_OM30D53E_(EE)
If the engine overheats
Towing a loaded trailer up a long, steep incline in temperatures
exceeding 30C (85F) may result in the engine overheating. If
the engine coolant temperature gauge indicates that the engine is
overheating, turn the air conditioning off immediately, leave the
road and stop the vehicle in a safe place. (P. 915)
When parking the vehicle
Always place wheel chocks under the wheels of both the vehicle
and trailer. Firmly set the parking brake and shift the shift lever
to P.
CAUTION
To avoid accident or injury
Do not tow a trailer when the compact spare tire is installed on your vehi-
cle.
Do not tow a trailer when the tire installed is repaired with the emergency
tire puncture repair kit.
Do not use cruise control (if equipped) or dynamic radar cruise control (if
equipped) when trailer towing.
Vehicle speed in towing
Observe the legal maximum speeds for trailer towing.
Before descending hills or long declines
Reduce speed and downshift. However, never downshift suddenly while
descending steep or long downhill grades.
Operation of the brake pedal
Do not hold the brake pedal depressed often or for long periods of time.
Doing so may result in the brake overheating or reduce braking effects.
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3014-5. Using the driving support system
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Driving
GS450h_300h_OM_OM30D53E_(EE)
CAUTION
To avoid operating the cruise control by mistake
Switch the cruise control off using the “ON/OFF” button when not in use.
Situations unsuitable for cruise control
Do not use cruise control in any of the following situations.
Doing so may result in loss of control and could cause an accident resulting
in death or serious injury.
In heavy traffic
On roads with sharp bends
On winding roads
On slippery roads, such as those covered with rain, ice or snow
On steep hills
Vehicle speed may exceed the set speed when driving down a steep hill.
When your vehicle is towing a trailer or during emergency towing
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CAUTION
To avoid inadvertent cruise control activation
Switch the cruise control off using the “ON/OFF” button when not in use.
Situations unsuitable for dynamic radar cruise control
Do not use dynamic radar cruise control in any of the following situations.
Doing so may result in inappropriate speed control and could cause an acci-
dent resulting in death or serious injury.
In heavy traffic
On roads with sharp bends
On winding roads
On slippery roads, such as those covered with rain, ice or snow
On steep downhills, or where there are sudden changes between sharp up
and down gradients
Vehicle speed may exceed the set speed when driving down a steep hill.
At entrances to expressways
When weather conditions are bad enough that they may prevent the sen-
sors from functioning correctly (fog, snow, sandstorm, heavy rain, etc.)
When an approach warning buzzer is heard often
When your vehicle is towing a trailer or during emergency towing
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4 4-5. Using the driving support system
Driving
GS450h_300h_OM_OM30D53E_(EE)
CAUTION
To avoid inadvertent dynamic radar cruise control with full-speed range
activation
Switch the cruise control off using the “ON/OFF” button when not in use.
Situations unsuitable for dynamic radar cruise control with full-speed range
Do not use dynamic radar cruise control with full-speed range in any of the
following situations.
Doing so may result in inappropriate speed control and could cause an acci-
dent resulting in death or serious injury.
In heavy traffic
On roads with sharp bends
On winding roads
On slippery roads, such as those covered with rain, ice or snow
On steep downhills, or where there are sudden changes between sharp up
and down gradients
Vehicle speed may exceed the set speed when driving down a steep hill.
At entrances to expressways
When weather conditions are bad enough that they may prevent the sen-
sors from functioning correctly (fog, snow, sandstorm, heavy rain, etc.)
When an approach warning buzzer is heard often
When your vehicle is towing a trailer or during emergency towing
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CAUTION
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 equip-
ment
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 mis-
interpreted 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,
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 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 free-
way or highway
When driving on a road with lane closures due to maintenance, or when
driving in a temporary lane
When towing a trailer
NOTICE
To prevent damage to or incorrect operation of the LKA system
Do not modify the headlights or attach stickers to the surface of the lights.
Do not modify the suspension, or replace them with non-genuine parts.
Do not install or place anything on the hood or the grille. Also, do not
install a grille guard (bull bars, kangaroo bar etc.).
Do not modify the sun visor or replace it with anything other than a genu-
ine Lexus product.
If your windshield needs repairs, contact any authorized Lexus dealer or
repairer, or another duly qualified and equipped professional.
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3584-5. Using the driving support system
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Lexus parking assist-sensor display
When an obstacle is detected while the rear view monitor system, is in use,
the warning indicator will appear in the top right of the screen even if the dis-
play setting has been set to off.
Sensor detection information
The sensor’s detection areas are limited to the areas around the vehicle’s
bumpers.
Certain vehicle conditions and the surrounding environment may affect the
ability of the sensor to correctly detect obstacles. Particular instances where
this may occur are listed below.
• There is dirt, snow or ice on the sensor. (Wiping the sensors will resolve
this problem.)
• The sensor is frozen. (Thawing the area will resolve this problem.)
In especially cold weather, if a sensor is frozen the screen may show an
abnormal display, or obstacles may not be detected.
• The sensor is covered in any way.
• The vehicle is leaning considerably to one side.
• On an extremely bumpy road, on an incline, on gravel, or on grass.
• The vicinity of the vehicle is noisy due to vehicle horns, motorcycle
engines, air brakes of large vehicles, or other loud noises producing
ultrasonic waves.
• There is another vehicle equipped with parking assist sensors in the
vicinity.
• The sensor is coated with a sheet of spray or heavy rain.
• The vehicle is equipped with a fender pole or wireless antenna.
• Towing eyelets are installed.
• The bumper or sensor receives a strong impact.
• The vehicle is approaching a tall or curved curb.
• In harsh sunlight or intense cold weather.
• The area directly under the bumpers is not detected.
• If obstacles draw too close to the sensor.
• A non-genuine Lexus suspension (lowered suspension etc.) is installed.
• People may not be detected if they are wearing certain types of clothing.
In addition to the examples above, there are instances in which, because of
their shape, signs and other objects may be judged by the sensor to be closer
than they are.
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Conditions under which the Blind Spot Monitor function may not function
correctly
The Blind Spot Monitor function may not detect vehicles correctly in the
following conditions:
• During bad weather such as heavy rain, fog, snow etc.
• When ice or mud etc. is attached to the rear bumper
• When driving on a road surface that is wet due to rain, standing water
etc.
• When there is a significant difference in speed between your vehicle and
the vehicle that enters the detection area
• When a vehicle is in the detection area from a stop and remains in the
detection area as your vehicle accelerates
• When driving up or down consecutive steep inclines, such as hills, a dip
in the road etc.
• When multiple vehicles approach with only a small gap between each
vehicle
• When vehicle lanes are wide, and the vehicle in the next lane is too far
away from your vehicle
• When the vehicle that enters the detection area is traveling at about the
same speed as your vehicle
• When there is a significant difference in height between your vehicle and
the vehicle that enters the detection area
• Directly after the BSM main switch is set to on
• When your vehicle is towing a trailer
Instances of the Blind Spot Monitor function unnecessarily detecting a
vehicle and/ or object may increase under the following conditions:
• When there is only a short distance between your vehicle and a guardrail,
wall etc.
• When there is only a short distance between your vehicle and a following
vehicle
• When vehicle lanes are narrow and a vehicle driving 2 lanes across from
your vehicle enters the detection area
• When items such as a bicycle carrier are installed on the rear of the vehi-
cle
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4294-5. Using the driving support system
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Driving
GS450h_300h_OM_OM30D53E_(EE)
Conditions under which the Rear Crossing Traffic Alert function will not
detect a vehicle
The Rear Crossing Traffic Alert function is not designed to detect the follow-
ing types of vehicles and/or objects.
Small motorcycles, bicycles, pedestrians etc.*
Vehicles approaching from directly behind
Guardrails, walls, signs, parked vehicles and similar stationary objects*
Vehicles moving away from your vehicle
Vehicles approaching from the parking spaces next to your vehicle*
Vehicles backing up in the parking space next to your vehicle*
*
: Depending on conditions, detection of a vehicle and/or object may occur.
Conditions under which the Rear Crossing Traffic Alert function may not
function correctly
The Rear Crossing Traffic Alert function may not detect vehicles correctly in
the following conditions:
During bad weather such as heavy rain, fog, snow etc.
When ice or mud etc. is attached to the rear bumper
When multiple vehicles approach continuously
Shallow angle parking
When a vehicle is approaching at high speed
When parking on a steep incline, such as hills, a dip in the road etc.
Directly after the BSM main switch is set to on
When your vehicle is towing a trailer
When items such as a bicycle carrier are installed on the rear of the vehicle
Directly after the hybrid system is started with the BSM main switch on
When the sensors cannot detect vehi-
cles because of obstacles