2012 Lexus HS250h brake

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2-4. Using other driving systems
HS250h_U_75050U
■Canceling and resuming the speed control
Pulling the lever toward you
cancels the cruise control.
The speed setting is also can-
celed when the brakes are
applied.
Pushing the lever up resumes
the cruise control and returns
vehicle speed to the set
speed.
Resuming is available when the
vehicle speed is more than
approximately 25 mph (40
km/h).

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When driving
HS250h_U_75050U
Driving in vehicle-to-vehicle distance control mode
This mode employs a radar sensor to detect the presence of vehicles up
to approximately 400 ft. (120 m) ahead, determines the current vehicle-
to-vehicle following distance, and operates to maintain a suitable follow-
ing distance from the vehicle ahead.
Note that vehicle-to-vehicle distance will close in when traveling on long
downhill slopes.
Example of constant speed cruising
When there are no vehicles ahead
The vehicle travels at the speed set by the driver. The desired vehicle-to-vehi-
cle distance can also be set by operating the vehicle-to-vehicle distance con-
trol.
Example of deceleration cruising
When the vehicle ahead is driving slower than the set speed
When a vehicle is detected running ahead of you, the system automatically
decelerates your vehicle. When a greater reduction in vehicle speed is nec-
essary, the system applies the brakes. A warning tone warns you when the
system cannot decelerate sufficiently to prevent your vehicle from closing in
on the vehicle ahead.

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HS250h_U_75050UExample of follow-up cruising
When following a vehicle driving slower than the set speed
The system continues follow-up cruising while adjusting for changes in the
speed of the vehicle ahead in order to maintain the vehicle-to-vehicle dis-
tance set by the driver.
Example of acceleration
When there are no longer any vehicles ahead driving slower than the
set speed.
The system accelerates until the set speed is reached. The system then
returns to constant speed cruising.
Approach warning
When your vehicle is too close to a vehicle ahead, and sufficient auto-
matic deceleration via the cruise control is not possible, the display will
flash and the buzzer will sound to alert the driver. An example of this
would be if another driver cuts in front of you while you are following a
vehicle. Apply the brakes to ensure an appropriate vehicle-to-vehicle dis-
tance.
■ Warnings may not occur when
In the following instances, there is a possibility that the warnings will not
occur:
● When the speed of the vehicle ahead matches or exceeds your vehicle
speed
● When the vehicle ahead is traveling at an extremely slow speed
● Immediately after the cruise control speed was set
● At the instant the accelerator is applied

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HS250h_U_75050U
■Certification
For vehicles sold in the U.S.A.
FCC ID: HYQDNMWR004
This device complies with part 15 of the FCC Rules. Operation is subject to the fol-
lowing two conditions: (1) This device may not cause harmful interference, and (2)
this device must accept any interference received, including interference that may
cause undesired operation.
FCC WARNING
Changes or modifications not expressly approved by the party responsible for
compliance could void the user’s authority to operate the equipment.
Radiofrequency radiation exposure Information:
This equipment complies with FCC radiation exposure limits set forth for an uncon-
trolled environment.
This equipment should be installed and operated with minimum distance of 20 cm
between the radiator (antenna) and your body.
This transmitter must not be co-located or operating in conjunction with any other
antenna or transmitter.
For vehicles sold in Canada
Operation is subject to the following two conditions: (1) this device may not cause
interference, and (2) this device must accept any interference, including interfer-
ence that may cause undesired operation of the device.
CAUTION
■Before using dynamic radar cruise control
Do not overly rely on vehicle-to-vehicle distance control.
Be aware of the set speed. If automatic deceleration/acceleration is not appropri-
ate, adjust the vehicle speed, as well as the distance between your vehicle and vehi-
cles ahead by applying the brakes etc.

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HS250h_U_75050U
CAUTION
■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 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 and 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 sensors
from functioning correctly (fog, snow, sandstorm, heavy rain, etc.)
●When an approach warning buzzer is heard often
■When the sensor may not be correctly detecting the vehicle ahead
Apply the brakes as necessary when any of the following types of vehicles are in
front of you.
As the sensor may not be able to correctly detect these types of vehicles, the
approach warning (→P. 222) will not be activated, and a fatal or serious accident
may result.
●Vehicles that cut in suddenly
●Vehicles traveling at low speeds
●Vehicles that are not moving
●Vehicles with small rear ends (trailers with no load on board etc.)
●Motorcycles traveling in the same lane

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When driving
HS250h_U_75050U
CAUTION
■Conditions under which the vehicle-to-vehicle distance control may not function
correctly
Apply the brakes as necessary in the following conditions as the radar sensor may
not be able to correctly detect vehicles ahead, and a fatal or serious accident may
result:
●When water or snow thrown up by the surrounding vehicles hinders the function-
ing of the sensor
●When your vehicle is pointing upwards (caused by a heavy load in the trunk etc.)
●When the road curves or when the lanes are narrow
●When steering wheel operation or your position in the lane is unstable
●When the vehicle ahead of you decelerates suddenly
■Handling the radar sensor
Observe the following to ensure the cruise control system can function effectively.
Otherwise, the system may not function correctly and could result in an accident.
●Keep the sensor and grille cover clean at all times.
Clean the sensor and grille cover with a soft cloth so you do not mark or damage
them.
●Do not subject the sensor or surrounding area to a strong impact.
If the sensor moves even slightly off position, the system may malfunction. If the
sensor or surrounding area is subject to a strong impact, always have the area
inspected and adjusted by a Lexus dealer.
●Do not disassemble the sensor.
●Do not attach accessories or stickers to the sensor, grille cover or surrounding
area.
●Do not modify or paint the sensor and grille cover.
●Do not replace them with non-genuine parts.

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When driving
HS250h_U_75050U
Indication on the multi-information displayWhile the LKA system is on, the lane line display and steering wheel dis-
play (in case of lane keeping assist function) are shown on the multi-infor-
mation display to inform that the LKA system is on. Steering wheel display
The lane keeping assist function is
active.
Dynamic radar cruise control
display
Lane line display
When thin lines are shown:
A lane marker is not recognized by
the system, or the LKA system
functions are temporarily can-
celed.
When solid lane lines are shown:
The lane departure warning func-
tion is active.
■Temporary cancellation of the LKA system functions
If any of the following occurs, the LKA system functions will be temporarily can-
celed. The functions will resume after the necessary operating conditions have
returned.
●The turn signal lever is operated.
●The steering wheel is turned as far as necessary to cause the vehicle to change
lanes.
●The brake pedal is depressed.
However, the lane keeping assist function will not resume even after the brake
pedal is released because depressing the brake pedal also cancels the dynamic
radar cruise control. (only lane departure warning function will resume)
●The vehicle speed deviates from the operating range of the LKA system func-
tions.

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HS250h_U_75050U
Driving assist systems
To help enhance driving safety and performance, the following systems
operate automatically in response to various driving situations. Be aware,
however, that these systems are supplementary and should not be relied
upon too heavily when operating the vehicle.
■ ABS (Anti-lock Brake System)
Helps to prevent wheel lock when the brakes are applied suddenly, or if
the brakes are applied while driving on a slippery road surface
■Brake assist
Generates an increased level of braking force after the brake pedal is
depressed when the system detects a panic stop situation
■VSC (Vehicle Stability Control)
Helps the driver to control skidding when swerving suddenly or turning on
slippery road surfaces
■TRAC (Traction Control)
Helps to maintain drive power and prevent the drive wheels from spinning
when starting the vehicle or accelerating on slippery roads
■EPS (Electric Power Steering)
Employs an electric motor to reduce the amount of effort needed to turn
the steering wheel
■Enhanced VSC (Enhanced vehicle stability control)
Provides cooperative control of the ABS, TRAC, VSC and EPS.
Helps to maintain directional stability when swerving on slippery road sur-
faces by controlling steering performance.
■PCS (Pre-Collision System) (if equipped)
→ P. 2 4 5