brake Lexus GS250 2014 Service Manual

3284-5. Using the driving support systems
GS350_250_OM_OM30E16E_(EE)
Hill-start assist control
To engage hill-start assist control,
further depress the brake pedal
when the vehicle is stopped com-
pletely.
A buzzer will sound once to indicate
the system is activated. The slip indica-
tor will also start flashing.
■Hill-start assist control operating conditions
●The system operates in the following situations:
• The shift lever is in a position other than P.
• The parking brake is not applied.
• The accelerator pedal is not depressed.
●Hill-start assist control cannot be operated while the slip indicator light is illumi-
nated.
■Hill-start assist control
●While hill-start assist control is operating, the brakes remain automatically applied
after the driver releases the brake pedal. The stop lights and the high mounted
stoplight turn on.
●Hill-start assist control operates for about 2 seconds after the brake pedal is
released.
●If the slip indicator does not flash and the buzzer does not sound when the brake
pedal is further depressed, slightly reduce the pressure on the brake pedal (do not
allow the vehicle to roll backward) and then firmly depress it again. If the system still
does not operate, check that the operating conditions explained above have been
met.
Assists with starting off and tempo rarily maintains braking power even
if the foot is removed from the brake pedal when starting off on an
incline or a slippery slope.
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3294-5. Using the driving support systems
4
Driving
GS350_250_OM_OM30E16E_(EE)
■Hill-start assist control buzzer
●When hill-start assist control is activated, the buzzer will sound once.
●In the following situations, hill-start assist control will be canceled and the buzzer
will sound twice.
• No attempt is made to drive the vehicle within approximately 2 seconds ofreleasing the brake pedal.
• The shift lever is moved to P.
• The parking brake is applied.
• The brake pedal is depressed again.
• The brake pedal has been depressed for more than approximately 3 minutes.
■If the slip indicator comes on
It may indicate a malfunction in the system. Contact any authorized Lexus dealer or
repairer, or another duly qualified and equipped professional.
CAUTION
■Hill-start assist control
●Do not overly rely on hill-start assist control. Hill-start assist control may not oper-
ate effectively on steep inclines and roads covered with ice.
●Unlike the parking brake, hill-start assist control is not intended to hold the vehi-
cle stationary for an extended period of time. Do not attempt to use hill-start
assist control to hold the vehicle on an incline, as doing so may lead to an acci-
dent.
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3304-5. Using the driving support systems
GS350_250_OM_OM30E16E_(EE)
PCS (Pre-Crash Safety system)∗
◆Pre-crash seat belts (front seat only)
If the pre-crash sensor detects that a collision is unavoidable, the pre-
crash safety system will retract the seat belt before the collision occurs.
The same will happen if the driver makes an emergency braking or
loses control of the vehicle. (→P. 4 0 )
◆Pre-crash brake assist
When there is a high possibility of a frontal collision, the system applies
greater braking force in relation to how strongly the brake pedal is
depressed.
◆Pre-crash braking
When there is a high possibility of a frontal collision, the system warns
the driver using a warning light, warning display and buzzer. If the sys-
tem determines that a collision is unavoidable, the brakes are automati-
cally applied to reduce the collision speed.
∗
: If equipped
When the radar sensor detects possibility of a frontal collision, the pre-
crash safety system such as the brakes and seat belts are automatically
engaged to lessen impact as well as vehicle damage.
The pre-crash safety system can be turned on and off as necessary by
operating the switch. ( →P. 3 3 1 )
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3334-5. Using the driving support systems
4
Driving
GS350_250_OM_OM30E16E_(EE)
■The pre-crash safety system is operational when
The PCS OFF switch is not pressed and the following conditions are met:
●Pre-crash warning:
• Vehicle speed is greater than about 15 km/h (10 mph).
• The speed at which your vehicle is approaching the obstacle or the vehicle run-ning ahead of you is greater than about 15 km/h (10 mph).
●Pre-crash seat belts (operating conditions A):
• Vehicle speed is greater than about 30 km/h (19 mph).
• The system detects sudden braking or skidding.
• The front occupants are wearing a seat belt.
●Pre-crash seat belts (operating conditions B):
• Vehicle speed is greater than about 5 km/h (4 mph).
• The speed at which your vehicle is approaching the obstacle or the vehicle run-ning ahead of you is greater than about 30 km/h (19 mph).
• The front occupants are wearing a seat belt.
●Pre-crash brake assist:
• Vehicle speed is greater than about 30 km/h (19 mph).
• The speed at which your vehicle is approaching the obstacle or the vehicle run- ning ahead of you is greater than about 30 km/h (19 mph).
• The brake pedal is depressed.
●Pre-crash braking:
• Vehicle speed is greater than about 15 km/h (10 mph).
• The speed at which your vehicle is approaching the obstacle or the vehicle run- ning ahead of you is greater than about 15 km/h (10 mph).
●Suspension control:
• Vehicle speed is greater than about 5 km/h (4 mph).
• The speed at which your vehicle is approaching the obstacle or the vehicle run-ning ahead of you is greater than about 30 km/h (19 mph).
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3344-5. Using the driving support systems
GS350_250_OM_OM30E16E_(EE)
●Pre-crash 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 40 km/h (25 mph).
• The speed at which your vehicle is approaching the vehicle running ahead of you is greater than about 40 km/h (25 mph).
• The steering is not being turned.
■Conditions that may trigger the system even if there is no danger of a collision
●When there is an object by the roadside at the entrance to a curve
●When passing an oncoming vehicle on a curve
●When driving over a narrow iron bridge
●When there is a metal object on the road surface
●When driving on an uneven road surface
●When passing an oncoming vehicle on a left-turn (left-hand drive vehicles) or right-
turn (right-hand drive vehicles)
●When your vehicle rapidly closes on the vehicle in front
●When a grade separation/interchange, sign, billboard, or other structure appears
to be directly in the vehicle’s line of travel
●When climbing a steep hill causes an overhead billboard or other metallic structure
to appear directly in the vehicle’s line of travel
When the system is activated in the situations described above, there is also a possi-
bility that the seat belts will retract quickly and the brakes will be applied with a force
greater than normal. When the seat belt is locked in the retracted position, stop the
vehicle in a safe place, release the seat belt and refasten it.
■Obstacles not detected
The sensor cannot detect plastic obstacles such as traffic cones. There may also be
occasions when the sensor cannot detect pedestrians, animals, bicycles, motorcy-
cles, trees, or snowdrifts.
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3404-5. Using the driving support systems
GS350_250_OM_OM30E16E_(EE)
CAUTION
■Cautions regarding the assist contents of the system
By means of alarms and brake control, the pre-crash safety system is intended to
assist the driver in avoiding collisions through the process of LOOK-JUDGE-ACT.
There are limits to the degree of assistance the system can provide, so please keep
in mind the following important points.
●Assisting the driver in watching the road
The pre-crash safety system is only able to detect obstacles directly in front of the
vehicle, and only within a limited range. It is not a mechanism that allows careless
or inattentive driving, and it is not a system that can assist the driver in low-visibil-
ity conditions. It is still necessary for the driver to pay close attention to the vehi-
cle’s surroundings.
●Assisting the driver in making correct judgment
When attempting to estimate the possibility of a collision, the only data available
to the pre-crash safety system is that from obstacles it has detected directly in
front of the vehicle. Therefore, it is absolutely necessary for the driver to remain
vigilant and to determine whether or not there is a possibility of collision in any
given situation.
●Assisting the driver in taking action
The pre-crash safety system’s braking assist feature is designed to help reduce
the severity of a collision, and so only acts when the system has judged that a col-
lision is unavoidable. This system by itself is not capable of automatically avoiding
a collision or bringing the vehicle to a stop safely. For this reason, when encoun-
tering a dangerous situation the driver must take direct and immediate action in
order to ensure the safety of all involved.
NOTICE
■Precautions for cleaning the driver monitor sensor
●Gently wipe the sensor with a soft cloth to prevent damage.
●Wipe any excess dirt with a cloth dampened with neutral detergent, all liquids
having been wringed out of the cloth. After that, wipe again with a dry cloth.
●Do not use benzene, thinner, glass cleaners, wax, etc.
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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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4396-1. Maintenance and care
6
Maintenance and care
GS350_250_OM_OM30E16E_(EE)
NOTICE
■To prevent paint deterioration and corrosion on the body and components (alu-
minum wheels etc.)
●Wash the vehicle immediately in the following cases:
• After driving near the sea coast
• After driving on salted roads
• If coal tar or tree sap is present on the paint surface
• If dead insects, insect droppings or bird droppings are present on the paintsurface
• After driving in an area contaminated with soot, oily smoke, mine dust, iron powder or chemical substances
• If the vehicle becomes heavily soiled with dust or mud
• If liquids such as benzene and gasoline are spilled on the paint surface
●If the paint is chipped or scratched, have it repaired immediately.
●To prevent the wheels from corroding, remove any dirt and store in a place with
low humidity when storing the wheels.
■Cleaning the exterior lights
●Wash carefully. Do not use organic substances or scrub with a hard brush.
This may damage the surfaces of the lights.
●Do not apply wax to the surfaces of the lights.
Wax may cause damage to the lenses.
■When using an automatic car wash (vehicle s with rain-sensing windshield wipers)
Turn off AUTO mode of the wiper to prevent the wiper from operating. ( →P. 2 7 2 )
If AUTO mode is selected, the wipers may operate and the wiper blades may be
damaged.
■When using a high-pressure car wash
●When washing the vehicle, do not let water from the high-pressure washer
directly hit the camera or the area around the camera. Due to the shock from
high-pressure water, it is possible that the device may not operate normally.
●Do not bring the nozzle tip close to boot s (rubber or resin manufactured cover),
connectors or the following parts. The parts may be damaged if they come into
contact with high-pressure water.
• Drivetrain system related parts
• Steering parts
• Suspension parts
•Brake parts
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4456-2. Maintenance
6
Maintenance and care
GS350_250_OM_OM30E16E_(EE)
■Where to go for maintenance service?
In order to maintain your vehicle in the best possible condition, Lexus recommends
that maintenance service operations as well as other inspections and repairs be car-
ried out by authorized Lexus dealers or repairers or other duly qualified and
equipped professionals. For repairs and services covered by your warranty, please
visit an authorized Lexus dealer or repairer, who will use genuine Lexus parts in
repairing any difficulties you may encounter. There can also be advantages in utiliz-
ing authorized Lexus dealers or repairers for non-warranty repairs and services, as
members of the Lexus network will be able to expertly assist you with any difficulties
you may encounter.
Your Lexus dealer or repairer, or another duly qualified and equipped professional
will perform all of the scheduled maintenance on your vehicle reliably and economi-
cally due to their experience with Lexus vehicles.
■Does your vehicle need repairs?
Be on the alert for changes in performance and sounds, and visual tip-offs that indi-
cate service is needed. Some important clues are:
●Engine missing, stumbling or pinging
●Appreciable loss of power
●Strange engine noises
●A fluid leak under the vehicle (However, water dripping from the air conditioning
system after use is normal.)
●Change in exhaust sound (This may indicate a dangerous carbon monoxide leak.
Drive with the windows open and have the exhaust system checked immediately.)
●Flat-looking tires, excessive tire squeal when cornering, uneven tire wear
●Vehicle pulls to one side when driven straight on a level road
●Strange noises related to suspension movement
●Loss of brake effectiveness, spongy feeling brake pedal, pedal almost touches the
floor, vehicle pulls to one side when braking
●Engine coolant temperature continually higher than normal (→P. 99)
If you notice any of these clues, take your vehicle to any authorized Lexus dealer or
repairer, or another duly qualified and equipped professional as soon as possible.
Your vehicle may need adjustment or repair.
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4486-3. Do-it-yourself maintenance
GS350_250_OM_OM30E16E_(EE)
Light bulbs (→P. 5 1 4 )
• Bulb with same number and wattage
rating as original
• Phillips-head screwdriver
•Flathead screwdriver
•Wrench
Radiator and condenser ( →P. 4 6 1 )
Tire inflation pressure ( →P. 4 8 3 )•Tire pressure gauge
• Compressed air source
Wa s h e r f l u i d ( →P. 4 6 5 )
• Water or washer fluid containing anti-
freeze (for winter use)
• Funnel (used only for adding water or washer fluid)
CAUTION
The engine compartment contains many mechanisms and fluids that may move sud-
denly, become hot, or become electrically energized. To avoid death or serious
injury, observe the following precautions.
■When working on the engine compartment
●Keep hands, clothing and tools away from the moving fan and engine drive belt.
●Be careful not to touch the engine, radiator, exhaust manifold, etc. right after driv-
ing as they may be hot. Oil and other fluids may also be hot.
●Do not leave anything that may burn easily, such as paper and rags, in the engine
compartment.
●Do not smoke, cause sparks or expose an open flame to fuel or the battery. Fuel
and battery fumes are flammable.
●Be extremely cautious when working on the battery. It contains poisonous and
corrosive sulfuric acid.
●Take care because brake fluid can harm your hands or eyes and damage painted
surfaces. If fluid gets on your hands or in your eyes, flush the affected area with
clean water immediately. If you still experience discomfort, consult a doctor.
ItemsParts and tools
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