light Lexus ES350 2010 s Repair Manual

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■Sensor detection information
●Certain vehicle conditions and the surrounding environment may affect the
ability of the sensor to correctly detect obstacles. Particular instances where this
may occur are listed below.
• There is dirt, snow or ice on the sensor.
• The sensor is frozen.
• The sensor is covered in any way.
• The vehicle is leaning considerably to one side.
• On an extremely bumpy road, on an incline, on gravel, or on grass
• The vicinity of the vehicle is noisy due to vehicle horns, motorcycle engines,air brakes of large vehicles, or other loud noises producing ultrasonic waves.
• There is another vehicle equipped with parking assist sensors in the vicinity.
• The sensor is coated with a sheet of spray or heavy rain
• The vehicle is equipped with a fender pole or wireless antenna.
• Towing eyelets are installed.
• The bumper or sensor receives a strong impact.
• The vehicle is approaching a tall or curved curb.
• In harsh sunlight or intense cold weather
In addition to the examples above, there are instances in which, because of their
shapes, signs and other objects may be judged by the sensor to be closer than they
are.
●The shape of the obstacle may prevent the sensor from detecting it. Pay particu-
lar attention to the following obstacles.
• Wires, fences, ropes etc.
• Cotton, snow and other materials that absorb radio waves
• Sharply-angled objects
• Low obstacles
• Tall obstacles with upper sections projecting outwards in the direction of your
vehicle

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Driving assist systems
When the VSC/TRAC systems are operatingIf the vehicle is in danger of slip-
ping, or if the front wheels spin, the
slip indicator light flashes to indi-
cate that the VSC/TRAC systems
have been engaged.
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 suppl ementary and should not be relied
upon too heavily when operating the vehicle.
■ 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.
■TRAC (Traction Control)
Maintains drive power and prevents the front wheels from spinning when
starting the vehicle or accelerating on slippery roads.
■PCS (Pre-Collision System) (if equipped)
o P. 1 76

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Disabling the TRAC/VSC systemsIf the vehicle gets stuck in fresh snow or mud, the TRAC/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 TRAC system only
To turn the TRAC system off,
quickly press and release the but-
ton.
A message will be shown on the
multi-information display.
Press the button again to turn the
system back on.
■Turning off both TRAC and VSC systems
To turn the TRAC and VSC sys-
tems off, press and hold the button
for more than 3 seconds while the
vehicle is stopped.
A message will be shown on the
multi-information display and VSC
off indicator light will come on.
Press the button again to turn the
systems back on.

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■Sounds and vibrations caused by the ABS, brake assist, VSC and TRAC 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 malfunction has occurred in any of these systems.
●Any of the following conditions may occur when the above systems are operat-
ing. 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.
■Reactivation of the TRAC /VSC systems after turning off the engine
Turning off the engine after turning off the TRAC/VSC systems will automatically
reactivate them.
■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 and VSC systems are turned off,
the systems will not turn on even when vehicle speed increases.
■If the slip indicator comes on
It may indicate a malfunction in the VSC and TRAC function. Contact your Lexus
dealer.

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CAUTION
■When the slip indicator flashes
This situation occurs immediately while VSC is activated. Always drive carefully.
Reckless driving may cause an accident. Exercise particular care when the indica-
tor 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 enhance vehicle stability and driving force, do not turn
the TRAC/VSC systems off unless necessary.
■Replacing tires
Make sure that all tires are of the same size, brand, tread pattern and total load
capacity. In addition, make sure that the tires are inflated to the recommended tire
pressure level.
The ABS and VSC systems will not function correctly if different tires are fitted on
the vehicle.
Contact your Lexus dealer for further information when replacing tires or wheels.

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■The pre-collision system is operational when
●Pre-collision seat belt (linked to the radar sensor)
• Vehicle speed is above 3 mph (5 km/h).
• The speed at which your vehicle is approaching the obstacle or oncomingvehicle exceeds 18 mph (30 km/h).
• The front occupants are wearing a seat belt.
●Pre-collision seat belts (linked to brake operation)
• Vehicle speed is above 9 mph (15 km/h).
• The system detects sudden braking or skidding.
• The front occupants are wearing a seat belt.
●Pre-collision brake assist
• Vehicle speed is above 18 mph (30 km/h).
• The speed at which your vehicle is approaching the obstacle or the vehicle is greater than about 18 mph (30 km/h).
• The brake pedal is depressed.
■Conditions that may trigger the system even if there is no danger of 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 there is a metal plate in the road in front of the vehicle on a downhill slope
●When there is a metal object such as a sign board in front of the vehicle on an
uphill slope
●When driving on an uneven road surface
●When passing an oncoming vehicle on a left-turn
●When your vehicle rapidly closes on the vehicle in front
●When your vehicle is skidding with the VSC system off
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.
■When there is a malfunction in the system
Warning lights and/or warning messages will turn on or flash. ( oP. 439, 449)

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CAUTION
■Handling the radar sensor
Observe the following to ensure the pre-collision system can function effectively.
●Keep the sensor and front grille clean at all times.
Clean the sensor and front grille with a soft cloth so you do not mark or damage
them.
●Do not subject the sensor or surrounding area to a strong impact.
If the sensor moves even slightly off position, the system may malfunction. If the
sensor or surrounding area are subject to a strong impact, always have the area
inspected and adjusted by a Lexus dealer.
●Do not disassemble the sensor.
●Do not attach accessories or stickers to the sensor, grille guard or surrounding
area.
●Do not modify or paint the sensor and grille cover.
■Limitations of the pre-collision system
Do not rely on the pre-collision system. Always drive safely, taking care to observe
your surroundings and checking for any obstacles or other road hazards.

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■Before towing
●Ensure that your vehicle’s tires are properly inflated. (oP. 396)
●Trailer tires should be inflated according to the trailer manufacturer's recom-
mendation.
●All trailer lights work to be legal.
●Confirm all lights work each time you connect them.
●Check that your vehicle remains level when a loaded or unloaded trailer is
hitched. Do not drive if the vehicle is not level, and check for improper tongue
load, overloading, worn suspension, or other possible causes.
●Make sure the trailer cargo is securely loaded.
●Check that your rear view mirrors conform to any federal, state/provincial or
local regulations. If they do not, install rear view mirrors appropriate for towing
purposes.
■Break-in schedule
Lexus recommends that you do not use a new vehicle or a vehicle with any new
power train components (engine, transmission, differential, wheel bearings, etc.) to
tow a trailer for the first 500 miles (800 km) of driving.
■Maintenance
●If you tow a trailer, your vehicle will require more frequent maintenance due to
the additional load. (See “Warranty and Services Guide/Owner's Manual Sup-
plement/ Scheduled Maintenance”.)
●Retighten the fixing bolts of the towing ball and bracket after approximately
600 miles (1000 km) of trailer towing.
CAUTION
■To avoid accident or injury
●The total trailer weight (trailer weight plus the weight of cargo) must not exceed
1000 lb. (450 kg).
●Do not exceed the trailer hitch assembly weight, gross vehicle weight, gross axle
weight and trailer tongue load capacities.
●Never load more weight in the back than in the front of the trailer. About 60% of
the load should be in the front half of the trailer, and the remaining 40% in the
r e a r.

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CAUTION
■Hitches
Trailer hitch assemblies have different weight capacities established by the hitch
manufacturer. Even though the vehicle may be physically capable of towing a
higher weight, the operator must never exceed the maximum weight rating speci-
fied for the trailer hitch.
●If you wish to install a trailer hitch, your Lexus dealer should be consulted.
●Use only a hitch that conforms to the total trailer weight requirement.
●Follow the directions supplied by the hitch manufacturer.
●Lubricate the hitch ball with a light coat of grease.
●Remove the trailer hitch whenever you are not towing a trailer. After removing
the hitch, seal any mounting holes in the vehicle body to prevent entry of any sub-
stances into the vehicle.
■When towing a trailer
●Never tap into your vehicle's hydraulic system, as this will lower the vehicle's
braking effectiveness.
●Never tow a trailer without using a safety chain securely attached to both the
trailer and the vehicle. If damage occurs to the coupling unit or hitch ball, there is
danger of the trailer wandering into another lane.
●Do not use cruise control/dynamic radar cruise control.
Doing so may result in inappropriate control of speed and could cause serious or
fatal accident.
NOTICE
■When installing a trailer hitch
●Use only the position recommended by your Lexus dealer. Do not install the
trailer hitch on the bumper; this may cause body damage.
●Do not use axle-mounted hitches, as they can cause damage to the axle housing,
wheel bearings, wheels or tires.
■Brakes
Lexus recommends trailers with brakes that conform to any applicable federal and
state/provincial regulations.

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Trailer towing tipsYour vehicle will handle differently when towing a trailer. The three main
causes of vehicle-trailer accidents are driver error, excessive speed and
improper trailer loading. Keep these in mind when towing.
● Before starting out, check the trailer’s lights and the vehicle-trailer
connections. Recheck after driving a short distance.
● Practice turning, stopping and reversing with the trailer attached in an
area away from traffic until you become accustomed to the feel of the
vehicle.
● Reversing with a trailer attached is difficult and requires practice. Grip
the bottom of the steering wheel and move your hand to the left to
move the trailer to the left. Move your hand to the right to move the
trailer to the right. (This is generally opposite to reversing without a
trailer attached.) Avoid sharp or prolonged turning. Have someone
guide you when reversing to reduce the risk of an accident.
● As stopping distance is increased when towing a trailer, vehicle-to-
vehicle distance should be increased. For each 10 mph (16 km/h) of
speed, allow at least one vehicle and trailer length.
NOTICE
■Safety chain
A safety chain must always be used between the towing vehicle and the trailer.
Leave sufficient slack in the chain for turns. The chain should cross under the trailer
tongue to prevent the tongue from dropping to the ground in the case that it
becomes damaged or separated. For the correct safety chain installation proce-
dure, ask your Lexus dealer.
■Do not directly splice trailer lights
Directly splicing may damage your vehicle's electrical system and cause a malfunc-
tion.