steering Lexus GS450h 2015 Service Manual

GS450h_OM_OM30F70U_(U)
2774-5. Using the driving support systems
4
Driving
●When driving on winding roads or roads that are uneven
●When driving on rough or unpaved roads
■When changing the tires
Depending on the tires used, sufficient performance may not be maintainable.
■Warning messages for LKA
Warning messages are used to indicate a system malfunction or to inform the driver
of the need for caution while driving. (→P. 516, 526)
CAUTION
■Before using the LKA system
Do not rely solely on the LKA system. The LKA system does not drive the vehicle
automatically, nor does it reduce the amount of care you need to take. As such, the
driver must always assume full responsibility for understanding his/her surround-
ings, for operating the steering wheel to correct the driving line, and for driving
safely.
Inappropriate or negligent driving could lead to an accident.
■To avoid operating the LKA by mistake
Switch the LKA off using the “LKA” switch when not in use.
GS450h_OM_OM30F70U_(U).book Page 277 Monday, January 19, 2015 9:34 AM

GS450h_OM_OM30F70U_(U)
2814-5. Using the driving support systems
4
Driving
Sport mode• SPORT S mode
Assists acceleration response by controlling the hybrid system.
When not in SPORT S mode and the driv ing mode select switch is turned to
the right, the “SPORT S” indicator come s on in the multi-information display,
and the Hybrid System Indicator changes to the tachometer. ( →P. 9 1 )
Also, on vehicles equipped with a
12.3-inch display, the driving mode
is also automatically displayed on
the side display. ( →P. 3 3 2 )
• SPORT S+ mode
Helps to ensure steering performance and driving stability by simul-
taneously controlling the steering and suspension in addition to the
hybrid system. Suitable for sporty driving.
When in SPORT S mode and the driving mode select switch is turned to the
right, the “SPORT S+” indicator comes on in the multi-information display, and
the Hybrid System Indicator changes to the tachometer. ( →P. 9 1 )
Also, on vehicles equipped with a
12.3-inch display, the driving mode
is also automatically displayed on
the side display. ( →P. 3 3 2 )
3
GS450h_OM_OM30F70U_(U).book Page 281 Monday, January 19, 2015 9:34 AM

283
GS450h_OM_OM30F70U_(U)4-5. Using the driving support systems
4
Driving
Driving assist systems
◆ABS (Anti-lock Brake System)
Helps to prevent wheel lock when th e 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
◆Enhanced VSC (Enhanced Vehicle Stability Control) (if equipped)
Provides cooperative control of the ABS, TRAC, VSC and EPS.
Helps to maintain directional stability when swerving on slippery road
surfaces by controlling steering performance.
◆TRAC (Traction Control)
Helps to maintain drive power and prevent the drive wheels from spin-
ning when starting the vehicle or accelerating on slippery roads
◆VGRS (Variable Gear Rati o 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
operate automatically in response to various driving situations. Be
aware, however, that these systems are supplementary and should not
be relied upon too heavily when operating the vehicle.
GS450h_OM_OM30F70U_(U).book Page 283 Monday, January 19, 2015 9:34 AM

284
GS450h_OM_OM30F70U_(U)
4-5. Using the driving support systems
◆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 accor-
dance with steering wheel movement
◆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)
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. 2 8 0 )
◆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 opera-
tion and vehicle speed
◆VDIM (Vehicle Dynamics Integrated Management)
Provides integrated control of the ABS, brake assist, TRAC, VSC and
EPS, VGRS (if equipped) and DRS (if equipped) systems
Helps to maintain vehicle stability when swerving on slippery road sur-
faces by controlling the brakes, hybrid system output, steering assist,
and steering ratio
◆PCS (Pre-Collision System) (if equipped)
→ P. 2 9 0
GS450h_OM_OM30F70U_(U).book Page 284 Monday, January 19, 2015 9:34 AM

GS450h_OM_OM30F70U_(U)
2874-5. Using the driving support systems
4
Driving
■When the message is displayed on the multi-information display showing that
TRAC has been disabled even if the VSC OFF switch has not been pressed
TRAC cannot be operated. Contact your Lexus dealer.
■VGRS is disabled when
VGRS may stop operating in the following situations.
In this event, the steering wheel may move from 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 battery is disconnected
The steering wheel may move from its straight forward position, but this will be cor-
rected automatically when driving.
■Sounds and vibrations caused by the ABS, brake assist, VSC, TRAC and VGRS sys-
tems
●A sound may be heard from the engine compartment when the brake pedal is
depressed repeatedly, when the hybrid system is started or just after the vehicle
begins to move. This sound does not indicate that a malfunction 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, 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.
■Reactivation of the TRAC/VSC systems
Even after the TRAC/VSC systems have been turned off, turning the hybrid system
off and then on again will automatically reactivate the TRAC/VSC systems.
■Reactivation of the TRAC system linked to vehicle speed
When only the TRAC system is turned off, the TRAC system will turn on when vehi-
cle speed increases. However, when both TRAC/VSC systems are turned off, the
systems will not turn on even when vehicle speed increases.
GS450h_OM_OM30F70U_(U).book Page 287 Monday, January 19, 2015 9:34 AM

288
GS450h_OM_OM30F70U_(U)
4-5. Using the driving support systems
■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 hybrid system 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.
CAUTION
■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 condi-
tions
The ABS is not designed to shorten the vehicle’s stopping distance. Always main-
tain a safe distance from the vehicle in front of you, especially in the following situa-
tions:
●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
■TRAC may not operate effectively when
Directional control and power may not be achievable while 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.
■When the VSC is activated
The slip indicator light flashes. Always drive carefully. Reckless driving may cause
an accident. Exercise particular care when the indicator light flashes.
■When the TRAC/VSC systems are turned off
Be especially careful and drive at a speed appropriate to the road conditions. As
these are the systems to help ensure vehicl e stability and driving force, do not turn
the TRAC/VSC systems off unless necessary.
GS450h_OM_OM30F70U_(U).book Page 288 Monday, January 19, 2015 9:34 AM

GS450h_OM_OM30F70U_(U)
2914-5. Using the driving support systems
4
Driving
◆Suspension control
When the system determines that there is a high possibility of a frontal
collision, the operation of AVS ( →P. 284) optimally controls the damp-
ing force of the shock absorber.
◆Steering control (if equipped)
XVehicles with VGRS
There is a high possibility of collision and if the steering wheel is oper-
ated, the steering gear ratio is changed by VGRS to help improve the
response to steering input.
XVehicles with LDH
There is a high possibility of collision and if the steering wheel is oper-
ated, the steering angles of the front and rear wheels and the heaviness
of the steering wheel are controlled by LDH, thus heightening respon-
siveness in response to the steering operation.
◆Driver monitor sy stem (if equipped)
When the system determines that there is a possibility of a collision, and
either the driver is not facing forward or the driver’s eyes are closed,
PCS warnings are given in advance to warn the driver. If the system
determines that the conditions to operate pre-collision alert braking
have been met even when the possibility of a collision increases further,
pre-collision alert braking will operate.
GS450h_OM_OM30F70U_(U).book Page 291 Monday, January 19, 2015 9:34 AM

294
GS450h_OM_OM30F70U_(U)
4-5. Using the driving support systems
■The pre-collision system is operational when
The PCS OFF switch is not pressed and the following conditions are met:
●Pre-collision warning:
• Vehicle speed is greater than about 10 mph (15 km/h).
• The speed at which your vehicle is approaching the obstacle or the vehicle run-ning ahead of you is greater than about 10 mph (15 km/h).
●Pre-collision seat belts (operating conditions A):
• Vehicle speed is greater than about 19 mph (30 km/h).
• The system detects sudden braking or skidding.
• The front occupants are wearing a seat belt.
●Pre-collision seat belts (operating conditions B):
• Vehicle speed is greater than about 4 mph (5 km/h).
• The speed at which your vehicle is approaching the obstacle or the vehicle run-ning ahead of you is greater than about 19 mph (30 km/h).
• The front occupants are wearing a seat belt.
●Pre-collision brake assist:
• Vehicle speed is greater than about 19 mph (30 km/h).
• The speed at which your vehicle is approaching the obstacle or the vehicle run- ning ahead of you is greater than about 19 mph (30 km/h).
• The brake pedal is depressed.
●Pre-collision braking:
• Vehicle speed is greater than about 10 mph (15 km/h).
• The speed at which your vehicle is approaching the obstacle or the vehicle run- ning ahead of you is greater than about 10 mph (15 km/h).
●Suspension control:
• Vehicle speed is greater than about 4 mph (5 km/h).
• The speed at which your vehicle is approaching the obstacle or the vehicle run-ning ahead of you is greater than about 19 mph (30 km/h).
●Pre-collision alert braking:
• The system determines that the driver is not facing forward, or that the driver’seyes are closed.
• Vehicle speed is greater than about 25 mph (40 km/h).
• The speed at which your vehicle is approaching the vehicle running ahead of you is greater than about 25 mph (40 km/h).
• The steering is not being turned.
GS450h_OM_OM30F70U_(U).book Page 294 Monday, January 19, 2015 9:34 AM

322
GS450h_OM_OM30F70U_(U)
4-6. Driving tips
CAUTION
■Driving with snow tires
Observe the following precautions to reduce the risk of accidents.
Failure to do so may result in a loss of vehicle control and cause death or serious
injury.
●Use tires of the specified size.
●Maintain the recommended level of air pressure.
●Do not drive in excess of 75 mph (120 km/h), regardless of the type of snow tires
being used.
●Use snow tires on all, not just some wheels.
●Do not use LKA (Lane-Keeping Assist) system.
■Driving with tire chains (vehicles with front and rear tires of the same size except
for the vehicles with LDH and 19 inch tires)
Observe the following precautions to reduce the risk of accidents.
Failure to do so may result in the vehicle being unable to be driven safely, and may
cause death or serious injury.
●Do not drive in excess of the speed limit specified for the tire chains being used,
or 30 mph (50 km/h), whichever is lower.
●Avoid driving on bumpy road surfaces or over potholes.
●Avoid sudden acceleration, abrupt steering, sudden braking and shifting opera-
tions that cause sudden engine braking.
●Slow down sufficiently before entering a curve to ensure that vehicle control is
maintained.
●Do not use LKA (Lane-Keeping Assist) system.
GS450h_OM_OM30F70U_(U).book Page 322 Monday, January 19, 2015 9:34 AM

325
GS450h_OM_OM30F70U_(U)
5Interior features
5-1. Remote Touch screen Remote Touch/12.3-inch display .......................................... 326
5-2. Using the air conditioning system and defogger
Front automatic air conditioning system .........335
Rear air conditioning system ..........................................355
Rear window and outside rear view mirror defoggers.......... 360
Windshield wiper de-icer ........ 361
5-3. Using the interior lights Interior lights list..........................363• Interior light ............................364
• Personal lights........................364
5-4. Using the storage features List of storage features.............366• Glove box............................... 368
• Console box ...........................369
• Cup holders............................ 370
• Auxiliary boxes...................... 372
Trunk features .............................. 373 5-5. Other interior features
Sun visors and vanity mirrors ................... 375
Clock................................................ 376
Ashtrays ..........................................377
Power outlets ............................... 378
Heated steering wheel ........... 380
Seat heaters/ seat ventilators ......................... 382
Armrest ..........................................386
Rear sunshade/ rear door sunshades .............. 387
Coat hooks ...................................390
Assist grips..................................... 391
Utility hook.................................... 392
Garage door opener................ 393
LEXUS Enform Safety Connect ..................................... 400
GS450h_OM_OM30F70U_(U).book Page 325 Monday, January 19, 2015 9:34 AM