2014 Lexus IS250 warning

2054-2. Driving procedures
4
Driving
IS250_EE(OM53C51E)
To set the parking brake, fully depress
the parking brake pedal with your left
foot while depressing the brake pedal
with your right foot.
(Depressing the pedal again releases
the parking brake.)
■Parking brake engaged warning buzzer
→P. 4 8 5
■Usage in winter time
→P. 2 8 8
Parking brake
Operating instructions
NOTICE
■Before driving
Fully release the parking brake.
Driving the vehicle with the parking brake set will lead to brake components overheat-
ing, which may affect braking performance and increase brake wear.

2274-5. Using the driving support systems
4
Driving
IS250_EE(OM53C51E)
■Cruise control can be set when
●The shift lever is in D.
●Range 4 or higher of D has been selected by using the paddle shift.
●Vehicle speed is above approximately 40 km/h (25 mph).
■Accelerating after setting the vehicle speed
●The vehicle can be accelerated normally. After acceleration, the set speed resumes.
●Even without canceling the cruise control, the set speed can be increased by first accel-
erating the vehicle to the desired speed and then pushing the lever down to set the new
speed.
■Automatic cruise control cancelation
Cruise control will stop maintaining the vehicle speed in any of the following situations.
●Actual vehicle speed falls more than approximately 16 km/h (10 mph) below the preset
vehicle speed.
At this time, the memorized set speed is not retained.
●Actual vehicle speed is below approximately 40 km/h (25 mph).
●VSC is activated.
●TRC is activated for a period of time.
●When the VSC or TRC system is turned off by pressing the VSC OFF switch.
■If the warning message for the cruise control is shown on the multi-information display
Press the “ON/OFF” button once to deactivate the system, and then press the button
again to reactivate the system.
If the cruise control speed cannot be set or if the cruise control cancels immediately after
being activated, there may be a malfunction in the cruise control system. Have the vehi-
cle inspected by any authorized Lexus dealer or repairer, or another duly qualified and
equipped professional.

2334-5. Using the driving support systems
4
Driving
IS250_EE(OM53C51E)
This mode employs a radar sensor to detect the presence of vehicles up to
approximately 120 m (400 ft.) ahead, determines the current vehicle-to-vehicle
following distance, and operates to maintain a suitable following 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-vehicle dis-
tance can also be set by operating the vehicle-to-vehicle distance control.
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 deceler-
ates your vehicle. When a greater reduction in vehicle speed is necessary, the system
applies the brakes. A warning tone warns you when the system cannot decelerate suf-
ficiently to prevent your vehicle from closing in on the vehicle ahead.
Example 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 distance 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 con-
stant speed cruising.
Driving in vehicle-to-vehicle distance control mode
1
2
3
4

2344-5. Using the driving support systems
IS250_EE(OM53C51E)
When your vehicle is too close to a vehicle ahead, and sufficient automatic
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 distance.
■Wa r n i n g s m a y n o t o c c u r w h e n
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
When constant speed control mode is selected, your vehicle will maintain a set
speed without controlling the vehicle-to-vehicle distance. Select this mode only
when vehicle-to-vehicle distance control mode does not function correctly due
to dirt etc.
Press the “ON/OFF” button to acti-
vate the cruise control.
Press the button again to deactivate the
cruise control.
Switch to constant speed control
mode.
(Push the lever forward and hold for
approximately 1 second.)
Constant speed control mode indicator will come on.
When in constant speed control mode, to return to vehicle-to-vehicle distance con-
trol mode, push the lever forward again and hold for approximately 1 second.
After the desired speed has been set, it is not possible to return to vehicle-to-vehicle
distance control mode.
If the engine switch is turned off and then turned to IGNITION ON mode again, the
vehicle will automatically return to vehicle-to-vehicle distance control mode.
Adjusting the speed setting: →P. 2 2 6
Canceling and resuming the speed setting: →P. 2 2 6
Approach warning
Selecting conventional constant speed control mode
1
2

2364-5. Using the driving support systems
IS250_EE(OM53C51E)
■Radar sensor and grille cover
Always keep the sensor and grille cover clean to ensure that the vehicle-to-vehicle dis-
tance control operates properly. (Some obstructions, such as snow, ice and plastic
objects, cannot be detected by the obstruction sensor.)
Dynamic radar cruise control is canceled if an obstruction is detected.
■Operation guide display
When the dynamic radar cruise control switch is operated, a guidance display is shown
on the meters for a few seconds as to how to operate the dynamic radar cruise control
switch or distance switch. (→P. 1 0 3 )
■Warning messages and buzzers for dynamic radar cruise control
Warning messages and buzzers are used to indicate a system malfunction or to inform
the driver of the need for caution while driving. (→P. 4 8 6 ) Grille cover
Radar sensor
1
2

2394-5. Using the driving support systems
4
Driving
IS250_EE(OM53C51E)
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 appropriate,
adjust the vehicle speed, as well as the distance between your vehicle and vehicles
ahead by applying the brakes etc.
■Cautions regarding the driving assist systems
Observe the following precautions.
Failure to do so may cause an accident resulting in death or serious injury.
●Assisting the driver to measure following distance
The dynamic radar cruise control is only intended to help the driver in determining
the following distance between the driver’s own vehicle and a designated vehicle
traveling ahead. It is not a mechanism that allows careless or inattentive driving, and it
is not a system that can assist the driver in low-visibility conditions. It is still necessary
for driver to pay close attention to the vehicle’s surroundings.
●Assisting the driver to judge proper following distance
The dynamic radar cruise control determines whether the following distance
between the driver’s own vehicle and a designated vehicle traveling ahead is appro-
priate or not. It is not capable of making any other type of judgement. Therefore, it is
absolutely necessary for the driver to remain vigilant and to determine whether or not
there is a possibility of danger in any given situation.
●Assisting the driver to operate the vehicle
The dynamic radar cruise control has no capability to prevent or avoid a collision with
a vehicle traveling ahead. Therefore, if there is ever any danger, the driver must take
immediate and direct control of the vehicle and act appropriately in order to ensure
the safety of all involved.
■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 accident result-
ing 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 sensors 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

2404-5. Using the driving support systems
IS250_EE(OM53C51E)
CAUTION
■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. 234) 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
■Conditions under which the vehicle-to-vehicle distance control may not function cor-
rectly
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 a the surrounding vehicles hinders the functioning
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 sen-
sor or surrounding area is subject to a strong impact, always have the area inspected
and adjusted by any authorized Lexus dealer or repairer, or another duly qualified
and equipped professional.
●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.

2444-5. Using the driving support systems
IS250_EE(OM53C51E)
■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. 486) 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. 241) becomes suitable for its oper-
ation, 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 for 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 bright 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