2017 Lexus GS300h power steering

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

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.

3625-2. Using the air conditio ning system and defogger
GS450h_300h_OM_OM30F92E_(EE)Turns the heated steering wheel on/off
The indicator light comes on when the
heater is operating.
●The heated steering wheel can be used when the power switch is in ON mode.
●The heated steering wheel will automatically turn off after about 30 minutes.
■Front seat heaters and ventilators (if equipped)/rear seat heaters (if equipped)
Seat heater switches
The indicator light (yellow) on the switch comes on when the seat heater is operat- ing.
Seat ventilator switches (front seats only)
The indicator light (green) on the switch co mes on when the seat ventilator is oper-
ating.
Level indicator lights
The seat heater temperature level or the seat ventilator fan speed level (for front
seats only) is displayed.
“AUTO” indicator lights
Heated steering wheel (if equipped)
Seat heaters/seat ventilators
Front seatsRear seats
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7
7-1. Essential information
When trouble arises
GS450h_300h_OM_OM30F92E_(EE)
If your vehicle has to be stopped in an emergency
Steadily step on the brake pedal with both feet and firmly depress it.
Do not pump the brake pedal repeatedly as this will increase the effort required to
slow the vehicle.
Shift the shift lever to N.
If the shift lever is shifted to N
After slowing down, stop the vehicle in a safe place by the road.
Stop the hybrid system.
If the shift lever cannot be shifted to N
Keep depressing the brake pedal with both feet to reduce vehicle speed as
much as possible.
To stop the hybrid system, press and
hold the power switch for 2 consec-
utive seconds or more, or press it
briefly 3 times or more in succes-
sion.
Stop the vehicle in a safe place by the road.
Only in an emergency, such as if it becomes impossible to stop the vehicle in
the normal way, stop the vehicl e using the following procedure:
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4
3
Press and hold for 2 seconds or more
or press briefly 3 times or more
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WARNING
■If the hybrid system has to be turned off while driving
Power assist for the steering wheel will be lost, making the steering wheel heavier to
turn. Decelerate as much as possible before turning off the hybrid system.
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7-2. Steps to take in an emergency
7
When trouble arises
GS450h_300h_OM_OM30F92E_(EE) Tighten down the towing eyelet
securely using a wheel nut wrench
or hard metal bar.
Securely attach cables or chains to the towing eyelet.
Take care not to damage the vehicle body.
Enter the vehicle being towed and start the hybrid system.
If the hybrid system does not start,
turn the power switch to ON mode.
Shift the shift lever to N and release the parking brake.
When the shift lever cannot be shifted: P. 229
■While towing
If the hybrid system is off, the power assist for the brakes and steering will not function,
making steering and braking more difficult.
■Wheel nut wrench
Wheel nut wrench is installed in trunk. ( P. 499, 511)
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4587-2. Steps to take in an emergency
GS450h_300h_OM_OM30F92E_(EE)
WARNING
Observe the following precautions.
Failure to do so may result in death or serious injury.
■When towing the vehicle
■While towing
●When towing using cables or chains, avoid sudden starts, etc. which place excessive
stress on the towing eyelets, cables or chains. The towing eyelets, cables or chains
may become damaged, broken debris ma y hit people, and cause serious damage.
●Do not turn the power switch off.
There is a possibility that the steering wheel is locked and cannot be operated.
■Installing towing eyelets to the vehicle
Make sure that towing eyelets are installed securely.
If not securely installed, towing ey elets may come loose during towing.
NOTICE
■To prevent damage to the vehicle when towing using a wheel-lift type truck
●Do not tow the vehicle from the rear when the power switch is off. The steering lock
mechanism is not strong enough to hold the front wheels straight.
●When raising the vehicle, ensure adequate ground clearance for towing at the oppo-
site end of the raised vehicle. Without adequate clearance, the vehicle cou ld be dam-
aged while being towed.
■To prevent damage to the vehicle when towing with a sling-type truck
Do not tow with a sling-type truck, either from the front or rear.
■To prevent damage to the vehicle during emergency towing
Do not secure cables or chains to the suspension components.
Be sure to transport the vehicle with all four
wheels raised off the ground. If the vehicle is
towed with the tires contacting the ground, the
drivetrain and related parts may be damaged,
an accident may occur due to a change in
direction of the vehicle or electricity generated
by the operation of the motor may cause a fire
to occur depending on the nature of the dam-
age or malfunction.

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7-2. Steps to take in an emergency
7
When trouble arises
GS450h_300h_OM_OM30F92E_(EE) *
: Driver’s and front passenger’s seat belt buzzer:
The driver’s and front passenger’s seat belt buzzer sounds to alert the driver and front
passenger that his or her seat belt is not fastened. The buzzer sounds intermittently for
30 seconds after the vehicle reaches a speed of 20 km/h (12 mph). Then, if the seat
belt is still unfastened , the buzzer will sound in a different tone for 90 more seconds.
■Front passenger detection sensor, seat belt reminder and warning buzzer
●If luggage is placed on the front passenger seat, the front passenger detection sensor
may cause the warning light to flash and the warning buzzer to sound even if a passen-
ger is not sitting in the seat.
●If a cushion is placed on the seat, the sensor may not detect a passenger, and the warn-
ing light may not operate properly.
■If the malfunction indicator lamp comes on while driving
The malfunction indicator lamp will come on if the fuel tank becomes completely empty.
If the fuel tank is empty, refuel the vehicle immediately. The malfunction indicator lamp
will go off after several trips.
If the malfunction indicator la mp does not go off, contact any authorized Lexus retailer or
Lexus authorized repairer, or any reliable repairer as soon as possible.
■Electric power steering system warning light (warning buzzer)
When the 12-volt battery charge becomes insufficient or the voltage temporarily drops,
the electric power steering system warning light may come on and the warning buzzer
may sound.
(If equipped)
Tire pressure warning light When the light comes on:
Low tire inflation pressure such as