2017 Lexus GS300h stop start

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4-2. Driving procedures
Driving
GS450h_300h_OM_OM30F92E_(EE)
Brake Hold
Turns the brake hold system onThe brake hold standby indicator
(green) comes on. While the system is
holding the brake, the brake hold oper-
ated indicator (yellow) comes on.
■Brake hold system operating conditions
The brake hold system cannot be turn ed on in the following conditions:
●The driver’s door is not closed.
●The driver is not wearing the seat belt.
●“EPB Activation Stopped Incompletely” or “Electronic Parking Brake Malfunction Visit
Your Dealer” is displayed on the multi-information display.
If any of the conditions above are detected when the brake hold system is enabled, the
system will turn off and the brake hold standby indicator light will go off. In addition, if any
of the conditions are detected while the sy stem is holding the brake, a warning buzzer
will sound and a message will be shown on th e multi-information display. The parking
brake will then be set automatically.
■Brake hold function
●If the brake pedal is left released for a pe riod of about 3 minutes after the system has
started holding the brake, th e parking brake will be set automatically. In this case, a
warning buzzer sounds and a message is shown on the multi-information display.
●To turn the system off while the system is holding the brake, firmly depress the brake
pedal and press the button again.
●The brake hold function may not hold the vehicle when the vehicle is on a steep incline.
In this situation, it may be necessary for the driver to apply the brakes. A warning
buzzer will sound and the multi-information disp lay will inform the driver of this situa-
tion. ( P. 466)
The brake hold system keeps the brake appl ied when the shift lever is in D, S or
N with the system on and the brake peda l has been depressed to stop the vehi-
cle. The system releases the brake when the accelerator pedal is depressed
with the shift lever in D or S to allow smooth start off.

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4-5. Using the driving support systems
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Driving
GS450h_300h_OM_OM30F92E_(EE) This mode employs a radar sensor to detect the presence of vehicles up to
approximately 100 m (328 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 button.
Example of deceleration cruising and follow-up cruising
When a preceding vehicle driving slower than the set speed appears
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 (the stop lights will come on at this time). The system will respond to
changes in the speed of the vehicle ahead in order to maintain the vehicle-to-vehicle
distance set by the driver. Approach wa rning warns you when the system cannot
decelerate sufficiently to prevent your vehicle from closing in on the vehicle ahead.
When the vehicle ahead of you stops, your ve hicle will also stop (vehicle is stopped by
system control). After the vehicle ahead starts off, pushing the cruise control lever up
or depressing the accelerator pedal will resume follow-up cruising.
Example of acceleration
When there are no longer any preceding vehicles 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 vehicl e-to-vehicle distance control mode
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3024-5. Using the driving support systems
GS450h_300h_OM_OM30F92E_(EE) Pressing the button changes the vehi-
cle-to-vehicle distance as follows:
Long
Medium Short
The vehicle-to-vehicle distance is set
automatically to long mode when the
power switch is turned ON mode.
If a vehicle is running ahead of you, the preceding vehicle mark will also be displayed.
Select a distance from the table below. Note that the distances shown corre-
spond to a vehicle speed of 80 km/h (50 mph). Vehicle-to-vehicle distance
increases/decreases in accordance with vehicle speed. When the vehicle is
stopped by system control, the vehicle-to-vehicle distance will be about 3 m
(10 ft.) to 5 m (16 ft.) regardless of the vehicle-to-vehicle distance setting.
After the vehicle ahead of you starts off,
push the lever up.
Your vehicle will also resume follow-up
cruising if the accelerator pedal is
depressed after the vehicle ahead of
you starts off.
Changing the vehicle-to -vehicle distance (vehicle-to-vehicle distance
control mode)
Preceding
vehicle mark
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2
3
Vehicle-to-vehicle distance setting s (vehicle-to-vehicle distance con-
trol mode)
Distance optionsVehicle-to-vehicle distance
LongApproximately 50 m (160 ft.)
MediumApproximately 40 m (130 ft.)
ShortApproximately 30 m (100 ft.)
Resuming follow-up cruising when the vehicle has been stopped by sys-
tem control (vehicle-to-vehicle distance control mode)

3244-5. Using the driving support systems
GS450h_300h_OM_OM30F92E_(EE)
Driving assist systems
◆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 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
◆TRC (Traction Control)
Helps to maintain drive power and prevent the drive wheels from spinning
when starting the vehicle or accelerating on slippery roads
◆VGRS (Variable Gear Ratio Steering) (if equipped)
Adjusts the front wheel turning angle in accordance with the vehicle speed
and steering wheel movement
To help enhance driving safety and performance, the following systems oper-
ate automatically in response to various driving situations. Be aware, however,
that these systems are suppl ementary and should not be relied upon too heav-
ily when operating the vehicle.

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4-5. Using the driving support systems
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Driving
GS450h_300h_OM_OM30F92E_(EE)
◆DRS (Dynamic Rear Steering) (if equipped)
Contributes to the turning characteristics and responsiveness of the vehicle
by slightly adjusting the rear wheel angle of the vehicle in accordance with
steering wheel movement
◆Hill-start assist control
Helps to prevent the vehicle from rolling backward when starting on an
incline.
◆EPS (Electric Power Steering)
Employs an electric motor to reduce the amount of effort needed to turn the
steering wheel
◆AVS (Adaptive Variable Susp ension system) (if equipped)
By independently controlling the damp ing force of the shock absorbers for
each of the 4 wheels according to the road and driving conditions, this system
helps riding comfort with a high level of stability, and helps good vehicle pos-
ture
When SPORT S+ mode is selected by the driving mode select switch, the
damping force is suitable for sporty driving ( P. 312)
◆LDH (Lexus Dynamic Handling system) (if equipped)
Provides independent control of the VGRS, DRS and EPS. Contributes to
turning characteristics at low speeds, responsiveness at medium speeds and
safety at high speeds by controlling the steering angle of the front and rear
wheels in accordance with the steering wheel operation and vehicle speed
◆VDIM (Vehicle Dynamics Integrated Management)
Provides integrated control of the ABS, brake assist, TRC, VSC, hill-start
assist control, EPS, VGRS (if equipped) and DRS (if equipped) systems
Helps to maintain vehicle stability when swerving on slippery road surfaces by
controlling the brakes, hybrid system output, steering assist, steering ratio and
rear wheel angle
◆Emergency brake signal
When the brakes are applie d suddenly, the stop lights automatically flash to
alert the vehicle behind

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4-5. Using the driving support systems
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Driving
GS450h_300h_OM_OM30F92E_(EE)
■Turning off both TRC and VSC systems
To turn the TRC and VSC systems off, press and hold for more than 3 seconds while
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-Crash Safety system), pre-crash brake assist and pre-
crash braking will also be disabled. The PCS (Pre-Crash Safety system) warning
light will come on and a message will be di splayed on the multi-information display.
(  P. 466)
■When the message is displayed on the mult i-information display showing that TRC has
been disabled even if has not been pressed
TRC and hill-start assist control cannot be operated. Contact any authorized Lexus
retailer or Lexus authorized repa irer, or any reliable repairer.
■VGRS is disabled when
VGRS may stop operating in the following situations.
In this event, the steering wheel may move fr om its straight forward position, but it will
return when the system restarts.
●The steering wheel is operated for an extended period of time while the vehicle is
stopped or is moving very slowly.
●When force is continuously applied for a long time with the steering wheel turned as far
as it will go.
The center position of the steering wheel may change when VGRS is disabled. How-
ever, the position will return to normal after VGRS is reactivated.
■When the 12-volt battery is disconnected
The steering wheel may move from its straight forward position, but this will be corrected
automatically when driving.

3284-5. Using the driving support systems
GS450h_300h_OM_OM30F92E_(EE)
■Sounds and vibrations caused by the ABS, brake assist, VSC, Hill-start assist control,
TRC and VGRS 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 operation sound
ECB operating sound may be heard in the follow ing 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 sounds 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 one or two minutes
passed after the stop of the hybrid system.
■EPS, VGRS and DRS 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 TRC and VSC systems
After turning the TRC and VSC systems off, the systems will be automatically re-enabled
in the following situations:
●When the power switch is turned off
●If only the TRC system is turned off, the TR C will turn on when vehicle speed increases
If both TRC and VSC systems are turned off, automatic re-enabling will not occur 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 N or P (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.

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4-5. Using the driving support systems
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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 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 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 operat ing 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 co ntrol. 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.