
3214-5. Using the driving support systems
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■Automatic cancelation of constant speed control mode
Constant speed control mode is automatica lly canceled in the following situations:
●Actual vehicle speed is more than approxim ately 10 mph (16 km/h) below the set vehi-
cle speed.
●Actual vehicle speed falls below approximately 25 mph (40 km/h).
●VSC is activated.
●TRAC is activated for a period of time.
●When the VSC or TRAC system is turned off by pressing the VSC OFF switch.
●Pre-collision braking is activated.
If constant speed control mode is automati cally canceled for any other reason, there may
be a malfunction in the system . Contact your Lexus dealer.
■Warning messages and buzzers for dynamic radar cruise control with full-speed range
Warning messages and buzzers are used to indicate a system malfunction or to inform
the driver of the need for ca ution while driving. If a warning message is shown on the
multi-information display, read the message and follow the instructions.
■When the sensor may not be correctly detecting the vehicle ahead
In the case of the following and depending on the conditions, operate the brake pedal
when deceleration of the system is insuff icient or operate the accelerator pedal when
acceleration is required.
As the sensor may not be able to correctly detect these types of vehicles, the approach
warning ( P. 318) may not be activated.
●Vehicles that cut in suddenly
●Vehicles traveling at low speeds
●Vehicles that are not moving in the same lane
●Vehicles with small rear ends (traile rs with no load on board, etc.)

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■Dynamic radar cruise control can be set when
●The shift lever is in D or range 4 or higher of S has been selected.
●Range 4 or higher of D has been selected by using the paddle shift.
(vehicles with padd le shift switches)
●Vehicle speed is above approximately 30 mph (50 km/h).
■Accelerating after setting the vehicle speed
The vehicle can accelerate by operating the accelerator pedal. After accelerating, the
set speed resumes. However, during vehicle-to-vehicle distance control mode, the vehi-
cle speed may decrease below the set speed in order to maintain the distance to the pre-
ceding vehicle.
■Automatic cancelation of vehicle- to-vehicle distance control mode
Vehicle-to-vehicle distance control mode is automatically canceled in the following situ-
ations.
●Actual vehicle speed falls below approximately 25 mph (40 km/h).
●VSC is activated.
●TRAC is activated for a period of time.
●When the VSC or TRAC system is turned off by pressing the VSC OFF switch.
●The sensor cannot detect correctly because it is covered in some way.
●Pre-collision braking is activated.
If vehicle-to-vehicle distance control mode is automatically canceled for any other rea-
son, there may be a malfunction in th e system. Contact your Lexus dealer.
■Automatic cancelation of constant speed control mode
Constant speed control mode is automatica lly canceled in the following situations:
●Actual vehicle speed is more than approxim ately 10 mph (16 km/h) below the set vehi-
cle speed.
●Actual vehicle speed falls below approximately 25 mph (40 km/h).
●VSC is activated.
●TRAC is activated for a period of time.
●When the VSC or TRAC system is turned off by pressing the VSC OFF switch.
●Pre-collision braking is activated.
If constant speed control mode is automati cally canceled for any other reason, there may
be a malfunction in the system . Contact your Lexus dealer.
■Warning messages and buzzers fo r dynamic radar cruise control
Warning messages and buzzers are used to indicate a system malfunction or to inform
the driver of the need for ca ution while driving. If a warning message is shown on the
multi-information display, read the message and follow the instructions.

3374-5. Using the driving support systems
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■Cruise control can be set when
●The shift lever is in D or range 4 or higher of S has been selected.
●Range 4 or higher has been selected by using the paddle shift.
(vehicles with paddle shift switches)
●Vehicle speed is above approximately 25 mph (40 km/h).
■Accelerating after setting the vehicle speed
●The vehicle can be accelerated by operating accelerator pedal. After accelerating, the
set speed resumes.
●Even without canceling the cruise control, th e 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 cancelation of cruise control
Cruise control is automatically canceled in any of the following situations.
●Actual vehicle speed falls more than appr oximately 10 mph (16 km/h) below the set
speed.
●Actual vehicle speed is below approximately 25 mph (40 km/h).
●VSC is activated.
●TRAC is activated for a period of time.
●When the VSC or TRAC system is turned off by pressing the VSC OFF switch.
■If “Cruise Control Malfunction Visit Your De aler” is displayed on the multi-information
display
Press the “ON/OFF” button once to deactiv ate 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 your Lexus dealer.

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◆ECB (Electronically Controlled Brake System)
The electronically controlled system generates braking force corresponding
to the brake operation
◆ABS (Anti-lock Brake System)
Helps to prevent wheel lock when the br akes are applied suddenly, or if the
brakes are applied while drivin g on a slippery road surface
◆Brake assist
Generates an increased level of br aking force after the brake pedal is
depressed when the system detects a panic stop situation
◆VSC (Vehicle Stability Control)
Helps the driver to contro l skidding when swerving suddenly or turning on
slippery road surfaces
◆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.
◆TRAC (Traction Control)
Helps to maintain drive power and pr event the drive wheels from spinning
when starting the vehicle or accelerating on slippery roads
◆Hill-start assist control
Prevents the vehicle from rolling backward when starting on an incline or slip-
pery slope
◆EPS (Electric Power Steering)
Employs an electric motor to reduce the amount of effort needed to turn the
steering wheel
Driving assist systems
To help enhance driving safety and perf ormance, the following systems oper-
ate automatically in response to variou s driving situations. Be aware, however,
that these systems are supplementary and should not be relied upon too heav-
ily when operating the vehicle.

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◆E-Four (AWD models)
Electronic On-Demand AWD system. Automatically switches from front-
wheel drive to all-wheel drive (AWD) according to the driving conditions,
helping to ensure reliable handling and st ability. Examples of conditions where
the system will switch to AWD are when cornering, going uphill, starting off or
accelerating, and when the road surface is slippery due to snow, rain, etc.
◆Adaptive Variable Suspension System (if equipped)
Controls the damping force of the shock absorber of each wheel according to
the road and driving conditions, helpin g achieve a comfortable ride, excellent
driveability and a high level of stability.
If SPORT S+ mode is selected using the driving mode select switch, the
damping force will become more su itable for sporty driving. (P. 378)
◆VDIM (Vehicle Dynamics Integrated Management)
Provides integrated control of the ABS, brake assist, TRAC, VSC, hill-start
assist control, and EPS systems
Helps to maintain vehicle stability when swerving on slippery road surfaces by
controlling the brakes and hybrid system output
◆Trailer Sway Control
Helps the driver to control trailer sway by selectively applying brake pressure
for individual wheels and reducing dr iving torque when trailer sway is
detected.
Trailer Sway Control is part of the VSC system and will not operate if VSC
turned off or experiences a malfunction.

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The slip indicator light will flash while
the TRAC/VSC/Trailer Sway Control/
ABS systems are operating.
If the vehicle gets stuck in mud, dirt or snow, the TRAC system may reduce
power from the hybrid system to the wheels. Pressing to turn the system
off may make it easier for you to rock the vehicle in order to free it.To turn the TRAC system off, quickly
press and release .
The “Traction Control Turned Off”
will be shown on the multi-informa-
tion display. Press again to
turn the system back on.
When the TRAC/VSC/Tra iler Sway Control/ABS systems are operat-
ing
Disabling the TRAC system

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■Turning off TRAC, VSC and Tr ailer Sway Control systems
To turn the TRAC, VSC and Trailer Sway Co ntrol systems off, press and hold for
more than 3 seconds whil e the vehicle is stopped.
The VSC OFF indicator light will come on an d the “Traction Control Turned Off” will be
shown on the multi-information display.
*
Press again to turn the systems back on.
*: On vehicles with PCS (Pre-Collision Sy stem), pre-collision brake assist and pre-
collision braking will also be disabled. ( P. 291)
■When the message is displayed on the mu lti-information display showing that TRAC
has been disabled even if has not been pressed
TRAC and hill-start assist control cannot be operated. Contact your Lexus dealer.
■Sounds and vibrations caused by the ABS, brake assist, TRAC, VSC, Trailer Sway Con-
trol and hill-start assist control systems
Any of the following conditions may occur when the above systems are operating. None
of these indicates that a malfunction has occurred.
●Vibrations may be felt through the vehicle body and steering.
●A motor sound may be heard after the vehicle comes to a stop.
■ECB operating sound
ECB operating sound may be heard in the followi ng cases, but it does not indicate that a
malfunction has occurred.
●Operating sound heard from the engine compartment when the brake pedal is oper-
ated.
●Motor sound of the brake system heard from the front part of the vehicle when the
driver’s door is opened.
●Operating sound heard from the engine compartment when 1 or 2 minutes passed
after the stop of the hybrid system.
■EPS operation sound
When the steering wheel is operated, a motor sound (whirring sound) may be heard.
This does not indicate a malfunction.
■Automatic reactivation of TRAC, VS C and Trailer Sway Control systems
After turning the TRAC, VSC and Trailer Sway Control systems off, the systems will be
automatically re-enabled in the following situations:
●When the power switch is turned off
●If only the TRAC system is turned off, the TRAC will turn on when vehicle speed
increases
If the TRAC, VSC and Trailer Sway Control systems are turned off, automatic re-
enabling will not occur when vehicle speed increases.

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■Reactivation of the TRAC system linked to vehicle speed
When only the TRAC system is turned off, the TRAC system will turn on when vehicle
speed increases. However, when TRAC, VSC and Trailer Sway Control systems are
turned off, the systems will not turn on even when vehicle speed increases.
■Reduced effectiveness of the EPS system
The effectiveness of the EPS system is reduced to prevent the system from overheating
when there is frequent steering input over an extended period of time. The steering
wheel may feel heavy as a result . Should this occur, refrain from excessive steering input
or stop the vehicle and turn the hybrid system off. The EPS system should return to nor-
mal within 10 minutes.
■Operating conditions of hill-start assist control
When the following four conditions are met, the hill-start assist control will operate:
●The shift lever is in a position other than P or N (when starting off forward/backward on
an upward incline).
●The vehicle is stopped.
●The accelerator pedal is not depressed.
●The parking brake is not engaged.
■Automatic system cancelation of hill-start assist control
The hill-start assist control will turn off in any of the following situations:
●The shift lever is moved to P or N.
●The accelerator pedal is depressed.
●The parking brake is engaged.
●Approximately 2 seconds elapse af ter the brake pedal is released.
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 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, grav el 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
■TRAC may not operate effectively when
Directional control and power may not be achievable wh ile driving on slippery road
surfaces, even if the TRAC system is operating.
Drive the vehicle carefully in conditions where stability and power may be lost.