brake Lexus GS250 2014 Owner's Guide

2864-5. Using the driving support systems
GS350_250_OM_OM30E16E_(EE)
To change the set speed, operate the lever until the desired set speed is
obtained.Increases the speed
Decreases the speed
Fine adjustment: Momentarily move
the lever in the desired direction.
Large adjustment: Hold the lever in
the desired direction.
The set speed will be increased or decreased as follows:
Fine adjustment: By approximately 1.6 km/h (1 mph) each time the lever is oper-
ated.
Large adjustment: The set speed can be increased or decreased continually until
the lever is released.
Pulling the lever toward you can-
cels the constant speed control.
The speed setting is also canceled
when the brakes are applied.
Pushing the lever up resumes the
constant speed control.
Resuming is available when the vehi-
cle speed is more than approximately
40 km/h (25 mph).
Adjusting the set speed
1
2
Canceling and resuming the constant speed control
1
2
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2934-5. Using the driving support systems
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Driving
GS350_250_OM_OM30E16E_(EE)
Pulling the lever toward you can-
cels the cruise control.
The speed setting is also canceled
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 vehi-
cle speed is more than approximately
40 km/h (25 mph).
Canceling and resuming the speed control
1
2
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2944-5. Using the driving support systems
GS350_250_OM_OM30E16E_(EE)
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
distance 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 decel-
erates 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 sufficiently to prevent your vehicle from closing in on the vehicle
ahead.
Driving in vehicle-to-vehicle distance control mode
1
2
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2954-5. Using the driving support systems
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Driving
GS350_250_OM_OM30E16E_(EE)
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
constant speed cruising.
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 vehi-
cle 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
Approach warning
3
4
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3014-5. Using the driving support systems
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Driving
GS350_250_OM_OM30E16E_(EE)
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.
■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 determin-
ing 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
appropriate 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 deter-
mine 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.
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3034-5. Using the driving support systems
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Driving
GS350_250_OM_OM30E16E_(EE)
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. 295) 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
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
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3204-5. Using the driving support systems
GS350_250_OM_OM30E16E_(EE)
Driving assist systems
◆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
◆VSC+ (Vehicle Stability Control+)
Provides cooperative control of the ABS, TRC, VSC and EPS.
Helps to maintain directional stability when swerving on slippery road
surfaces by controlling steering performance.
◆TRC (Traction Control)
Helps to maintain drive power and prevent the drive wheels from spin-
ning when starting the vehicle or accelerating on slippery roads
◆Hill-start assist control
→ P. 328
To help enhance driving safety and performance, the following systems
operate automatically in response to various driving situations. Be
aware, however, that these system s are supplementary and should not
be relied upon too heavily when operating the vehicle.
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3214-5. Using the driving support systems
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Driving
GS350_250_OM_OM30E16E_(EE)
◆EPS (Electric Power Steering)
Employs an electric motor to reduce the amount of effort needed to
turn the steering wheel
◆AVS (Adaptive Variable Suspension system) (if equipped)
By independently controlling the damping force of the shock absorbers
for each of the 4 wheels according to the road and driving conditions,
this system helps riding comfort with superior steering stability, and
helps good vehicle posture
When SPORT S+ mode is selected by the driving mode select switch,
the damping force is suitable for sporty driving ( →P. 317)
◆VDIM (Vehicle Dynamics Integrated Management)
Provides integrated control of the ABS, brake assist, TRC, VSC, hill-
start assist control and EPS systems
Helps to maintain vehicle stability when swerving on slippery road sur-
faces by controlling the brakes, engine output, steering assist, and
steering ratio
◆PCS (Pre-Crash Safety system) (if equipped)
→ P. 3 3 0
◆Emergency brake signal
When the brakes are applied suddenly, the stop lights automatically
flash to alert the vehicle behind.
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3244-5. Using the driving support systems
GS350_250_OM_OM30E16E_(EE)
■When the message is displayed on the multi-information display showing that TRC
has been disabled even if the VSC OFF switch has not been pressed
TRC cannot be operated. Contact any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional.
■Sounds and vibrations caused by the ABS, brake assist, VSC and TRC systems
●A sound may be heard from the engine compartment when the engine is started or
just after the vehicle begins to move. This sound does not indicate that a malfunc-
tion has occurred in any of these 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.
• The brake pedal may pulsate slightly after the ABS is activated.
• The brake pedal may move down slightly after the ABS is activated.
■EPS operation sound
When the steering wheel is operated, a motor sound (whirring sound) may be heard.
This does not indicate a malfunction.
■Reactivation of the TRC/VSC systems
Even after the TRC/VSC systems have been turned off, turning the engine off and
then on again will automatically reactivate the TRC/VSC systems.
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3254-5. Using the driving support systems
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Driving
GS350_250_OM_OM30E16E_(EE)
■Reactivation of the TRC system linked to vehicle speed
When only the TRC system is turned off, the TRC system will turn on when vehicle
speed increases. However, when both TRC and VSC systems are turned off, the sys-
tems 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 overheat-
ing when there is frequent steering input over an extended period of time. The steer-
ing wheel may feel heavy as a result.
* Should this occur, refrain from excessive
steering input or stop the vehicle and turn the engine off. The EPS system should
return to normal within 10 minutes.
*: If the LKA (Lane-Keeping Assist) system cannot operate in this case, a warning
message will be shown on the multi-information display.
■Operating conditions of emergency brake signal
When the following three conditions are met, the emergency brake signal will oper-
ate:
●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
vehicle deceleration that this is a sudden braking operation.
■Automatic system cancelation of emergency brake signal
The emergency brake signal will turn off 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 oper-
ation.
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