2724-5. Using the driving support systems
GS450h_300h_OM_OM30F92E_(EE)
WARNING
■Pre-crash braking*3
●When the pre-crash braking function is operating, a large amount of braking force will be applied.
●If the vehicle is stopped by the operation of the pre-crash braking function, the pre-crash braking function operation will be canceled after approximately 2 seconds.Depress the brake pedal as necessary.
●The pre-crash braking function may not operate if certain operations are performedby the driver. If the accelerator pedal is being depressed strongly or the steeringwheel is being turned, the system may determine that the driver is taking evasive
action and possibly prevent the pre-crash braking function from operating.
●In some situations, while the pre-crash braking function is operating, operation of thefunction may be canceled if the accelerator pedal is depressed strongly or the steer-
ing wheel is turned and the system determines that the driver is taking evasive action.
●If the brake pedal is being depressed, the system may determine that the driver is tak-ing evasive action and possibly delay the operation timing of the pre-crash braking
function.
*3: Depending on the region in which the vehicle was sold, the pre-crash braking func-
tion may not be available.
■When to disable the pre-crash safety system
In the following situations, disable the system, as it may not operate properly, possibly
leading to an accident resulting in death or serious injury:
●When the vehicle is being towed
●When your vehicle is towing another vehicle
●When transporting the vehicle via truck, boat, train or similar means of transportation
●When the vehicle is raised on a lift with the hybrid system on and the tires are allowed to rotate freely
●When inspecting the vehicle using a drum tester such as a chassis dynamometer orspeedometer tester, or when using an on vehicle wheel balancer
●When a strong impact is applied to the front bumper or front grille, due to an accident
or other reasons
●If the vehicle cannot be driven in a stable manner, such as when the vehicle has beenin an accident or is malfunctioning
●When the vehicle is driven in a sporty manner or off-road
●When the tires are not properly inflated
●When the tires are very worn
●When tires of a size other than specified are installed
●When tire chains are installed
●When a compact spare tire or an emergency tire puncture repair kit is used
●If equipment (snow plow, etc.) that may obstruct the radar sensor or camera sensor istemporarily installed to the vehicle
2854-5. Using the driving support systems
4
Driving
GS450h_300h_OM_OM30F92E_(EE)
WARNING
■Before using LKA system
Do not rely solely upon the LKA system. Th e LKA system does not automatically drive the vehicle or reduce the amount of attention that must be paid to the area in front of
the vehicle. The driver must always assume full responsibility for driving safely by pay- ing careful attention to the surrounding conditions and operating the steering wheel tocorrect the path of the vehicle. Also, the driver must take adequate breaks when
fatigued, such as from driving for a long period of time. Failure to perform appropriate driving operat ions and pay careful attention may lead to an accident, resulting in death or serious injury.
■To avoid operating LKA system by mistake
When not using the LKA system, use the LKA switch to turn the system off.
■Situations unsuitable for LKA system
Do not use the LKA system in the following situations. The system may not operate properly and le ad to an accident, resulting in death or serious injury.
●A spare tire, tire chains, etc. are equipped.
●When the tires have been excessively worn, or when the tire inflation pressure is low.
●Tires which differ by structure, manufacturer, brand or tread pattern are used.
●Objects or patterns that could be mistaken for white (yellow) lines are present on the side of the road (guardrails, cu rbs, reflective poles, etc.).
●Vehicle is driven on a snow-covered road.
●White (yellow) lines are difficult to see due to rain, snow, fog, dust, etc.
●Asphalt repair marks, white (yellow) line marks, etc. are present due to road repair.
●Vehicle is driven in a temporary lane or restricted lane due to construction work.
●Vehicle is driven on a road surface which is slippery due to rainy weather, fallen snow, freezing, etc.
●Vehicle is driven in traffic lanes other than on highways and freeways.
●Vehicle is driven in a construction zone.
●Vehicle is towing a trailer or another vehicle. (vehicles with towing package)
■Preventing LKA system malfunctions and operations performed by mistake
●Do not modify the headlights or place stickers, etc. on the surface of the lights.
●Do not modify the suspension etc. If the suspension etc. needs to be replaced, con- tact any authorized Lexus retailer or Le xus authorized repairer, or any reliable
repairer.
●Do not install or place anything on the hood or grille. Also, do not install a grille guard (bull bars, kangaroo bar, etc.).
●If your windshield needs repairs, contac t any authorized Lexus retailer or Lexus authorized repairer, or any reliable repairer.
3294-5. Using the driving support systems
4
Driving
GS450h_300h_OM_OM30F92E_(EE)
■Automatic system cancelation of hill-start assist control
The hill-start assist control will be canc eled in any of the following situations;
●The shift lever is shifted to N or P.
●The accelerator pedal is depressed.
●The parking brake is engaged.
●Approximately 2 seconds elapse after the brake pedal is released.
■Operating conditions of emergency brake signal
When the following three conditions are me t, the emergency brake signal will operate:
●The emergency flashers are off.
●Actual vehicle speed is over 55 km/h (35 mph).
●The brake pedal is depressed in a manner that cause the system to judge from the vehi- cle deceleration that this is a sudden braking operation.
■Automatic system cancelation of emergency brake signal
The emergency brake signal will turn of f in any of the following situations:
●The emergency flashers are turned on.
●The brake pedal is released.
●The system judges from the vehicle deceleration that is not a sudden braking operation.
WARNING
■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
■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 the hill-start assist control. The 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.
3344-6. Driving tips
GS450h_300h_OM_OM30F92E_(EE)
Winter driving tips
●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 vehicles with front and rear tires of differing
sizes and vehicles with LDH and 19 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.
Carry out the necessary preparations an d 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
3364-6. Driving tips
GS450h_300h_OM_OM30F92E_(EE)
Vehicles with front and rear tires of the same size except for the vehicles with
LDH and 19 inch tires
Use the correct tire chain size when mounting the tire chains.
Chain size is regulated for each tire size.
Side chain
(3 mm [0.12 in.] in diameter)
Cross chain
(4 mm [0.16 in.] in diameter)
Vehicles with front and rear tires of differing sizes and vehicles with LDH and
19 inch tires
Tire chains cannot be mounted.
Snow tires should be used instead.
Regulations regarding the use of tire chai ns vary depending on location and type
of road. Always check local regulations before installing chains.
Selecting tire chains
1
2
Regulations on the use of tire chains
3374-6. Driving tips
4
Driving
GS450h_300h_OM_OM30F92E_(EE)
If heavy snow or icy condition is expected, shift the rest position manually.
Grip the hook section of the wiper arm firmly when shifting the wiper position.
■To rest position
Raise the wiper in line with the wind-
shield.
You can stand the wipers up for the rest position.
★ : More than 10 cm (3.9 in.)
■To retract position
Lower the wipers by pressing on the
upper part of the hook section.
■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 0.5
1.0 km (1/4 1/2 mile).
●Install tire chains following the instructions provided with the tire chains.
Shifting the windshield wiper position
3384-6. Driving tips
GS450h_300h_OM_OM30F92E_(EE)
WARNING
■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 at speeds in excess of the speed limit or the speed limit specified for the
snow tires being used.
●Use snow tires on all, not just some wheels.
■Driving with tire chains (vehicles with front and rear tires of the same size except for
the vehicles with LDH and 19 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 sp ecified for the tire chains being used, or 50 km/h (30 mph), whichever is lower.
●Avoid driving on bumpy road surfaces or over potholes.
●Avoid sudden acceleration, abrupt steerin g, sudden braking and shifting operations that cause sudden engine braking.
●Slow down sufficiently before entering a curve to ensure that vehicle control is main-tained.
●Do not use LKA (Lane-Keeping Assist) system. (if equipped)
NOTICE
■Repairing or replacing snow tires
Request repairs or replacement of snow ti res from Lexus dealers or legitimate tire
retailers. This is because the removal and attachment of snow tires affects the operation of thetire pressure warning va lves and transmitters.
■Fitting tire chains (vehicles with front and rear tires of the same size except for the vehicles with LDH and 19 inch tires)
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. 337)
Failure to do so may result in damage to the wipers and/or the hood.
4206-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30F92E_(EE)
■When rotating the tires (vehicles with the tire pressure warning system featuring a tire inflation pressure display function)
Make sure that the power switch is off. If the tires are rotated while the power switch is in
ON mode, the tire position information will not be updated. If this accidentally occurs, either turn the power switch to off and then to ON mode, orinitialize the system after checking that the tire pressure is properly adjusted.
■Low profile tires (except 225/50R17 tires)
Generally, low profile tires will wear more rapidly and tire grip performance will be reduced on snowy and/or icy roads when comp ared 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. ( P. 336)
■If the tread on snow tires wears down below 4 mm (0.16 in.)
The effectiveness of the tires as snow tires is lost.
■Situations in which the tire pressure warning system may not operate properly (vehi- cles with the tire pressure warning system)
●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.• 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 vehi cle, particularly around the wheels or wheel housings.
• If the tire inflation pressure is extr emely higher than the specified level. • If wheel without the tire pressure warning valve and transmitter 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 that generates st rong radio waves or electrical noise
• When carrying a portable radio, cellular phone, cordless phone or other wireless communication deviceVehicles with the tire inflation pressure display function: If tire position information is
not correctly 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 rapi dly for example when a tire has burst, the warning may not function.