wheel Lexus GS250 2014 Service Manual

3094-5. Using the driving support systems
4
Driving
GS350_250_OM_OM30E16E_(EE)
When the LKA system is on, the lane line display and steering wheel dis-
play are shown.Lane keeping assist function
operation indication
Steering wheel displayed:
Indicates that the function is currently
operating. (If the lane departure warn-
ing operates at this time, the steering
wheel flashes orange.)
Steering wheel not displayed:
Indicates that the function is not cur-
rently operating. (When the lane
keeping assist function is canceled,
the buzzer will beep twice.)
Dynamic radar cruise control dis-
play
Lane departure warning function
indication (when the inside of the
white line is white):
The function has recognized lane
markers. (If the lane departure warn-
ing operates at this time, the lines flash
orange.)
Lane departure warning function
indication (when the inside of the
white line is black):
A lane marker is not recognized by
the system, or the LKA system func-
tions are temporarily canceled.
Indication on the multi-information display
1
2
3
4
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3104-5. Using the driving support systems
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■Temporary cancelation of the LKA system functions
If any of the following occurs, the LKA system functions will be temporarily canceled.
The functions will resume after the necessary operating conditions have returned.
●The steering wheel is turned as far as necessary to cause the vehicle to change
lanes.
●When the system detects no-handed driving. (The lane keeping assist function will
be temporarily canceled, but the lane departure warning function will continue.)
●The turn signal lever is operated.
●The vehicle speed deviates from the operating range of the LKA system functions.
(The buzzer will beep twice when the lane keeping assist function is being can-
celed.)
●When the lane lines cannot be recognized while driving. (The buzzer will beep
twice when the lane keeping assist function is being canceled.)
●The wiper switch is set on high speed mode or is set on AUTO mode with wipers
operating at high speed. (The lane keeping assist function will be temporarily can-
celed, but the lane departure warning function will continue.)
●If the vehicle crosses a line for approximately half a minute or more. (The lane keep-
ing assist function will be temporarily canceled, but the lane departure warning
function will continue.)
●When the lane departure warning function is activated.
The lane departure warning function will not operate again for a several seconds
after it has been activated, even if the vehicle leaves the lane again.
■The lane departure warning
It may be difficult to feel the sensory warning depending on the road conditions.
■No-handed driving warning
If the steering wheel is not operated for approximately 15 seconds on a straight road
or approximately 5 seconds on a curve, the buzzer will beep twice, indicators on the
multi-information display will flash, and the lane keeping assist function will be tem-
porarily canceled. If you drive the vehicle with your hands lightly touching the steer-
ing wheel, this may also be detected as no-handed driving.
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3124-5. Using the driving support systems
GS350_250_OM_OM30E16E_(EE)
●When driving on a road surface that is wet due to rain, previous rainfall, standing
water, etc.
●When the vehicle experiences strong up-and-down motion such as when driving
on an extremely rough road or on a seam in the pavement
●When headlight brightness at nighttime is reduced due to dirt on the lenses, or
when the headlights are misaligned
●When driving with a strong crosswind
●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. 555, 563)
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.
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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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3224-5. Using the driving support systems
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The slip indicator light will flash
while the TRC/VSC systems are
operating.
If the vehicle gets stuck in fresh snow or mud, the TRC and VSC systems
may reduce power from the engine to the wheels. You may need to turn
the system off to enable you to rock the vehicle in order to free it.
■Turning off the TRC system only
To turn the TRC system off,
quickly press and release the
switch.
The “TRC OFF” will be shown on
the multi-information display. Press
the switch again to turn the system
back on.
When the TRC/VSC systems are operating
Disabling the TRC/VSC systems
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3244-5. Using the driving support systems
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■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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3274-5. Using the driving support systems
4
Driving
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CAUTION
■Replacing tires
Make sure that all tires are of the specified size, brand, tread pattern and total load
capacity. In addition, make sure that the tires are inflated to the recommended tire
inflation pressure level.
The ABS, TRC and VSC systems will not function correctly if different tires are
installed on the vehicle.
Contact any authorized Lexus dealer or repairer, or another duly qualified and
equipped professional for further information when replacing tires or wheels.
■Handling of tires and the suspension
Using tires with any kind of problem or modifying the suspension will affect the
driving assist systems, and may cause a system to malfunction.
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3554-6. Driving tips
4
Driving
GS350_250_OM_OM30E16E_(EE)
Perform the following according to the driving conditions:
●Do not try to forcibly open a window or move a wiper that is frozen.
Pour warm water over the frozen area to melt the ice. Wipe away the
water immediately to prevent it from freezing.
●To ensure proper operation of the climate control system fan, remove
any snow that has accumulated on the air inlet vents in front of the wind-
shield.
●Check for and remove any excess ice or snow that may have accumu-
lated on the exterior lights, vehicle’s roof, chassis, around the tires or on
the brakes.
●Remove any snow or mud from the bottom of your shoes before getting
in the vehicle.
Accelerate the vehicle slowly, keep a safe distance between you and the
vehicle ahead, and drive at a reduced speed suitable to road conditions.
Park the vehicle and move the shift lever to P without setting the parking
brake. The parking brake may freeze up, preventing it from being
released. If necessary, block the wheels to prevent inadvertent sliding or
creeping.
Before driving the vehicle
When driving the vehicle
When parking the vehicle
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