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1-7. Safety information
1
Before driving
08_IS350/250_U_(L/O_0708)
CAUTION
■Modification and disposal of SRS airbag system components
Do not dispose of your vehicle or perform any of the following modifications with-
out consulting your Lexus dealer.
The SRS airbag may malfunction or deploy (inflate) accidentally, causing death or
serious injury.
●Installation, removal, disassembly and repair of the SRS airbags
●Repairs, modifications, removal or replacement of the steering wheel, instrument
panel, dashboard, seats or seat upholstery, front, side and rear pillars or roof side
rails
●Repairs or modifications of the front fender, front bumper, or side of the occupant
compartment
●Installation of snow plows, winches, etc. to the front grille (bull bars, kangaroo bar
etc.)
●Modifications to the vehicle's suspension system
●Installation of electronic devices such as mobile two-way radios or CD players
●Modifications to your vehicle for a person with a physical disability
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2-1. Driving procedures
08_IS350/250_U_(L/O_0708)
NOTICE
■If you hear a squealing or scraping noise (brake pad wear limit indicators)
Have your Lexus dealer check and replace the brake pads as soon as possible.
The rotor damage can result if the pads are not replaced when needed.
Front brake only: Moderate levels of the brake pad and disc wear allow enhanced
front braking power. As a result, the discs may wear more quickly than conventional
brake discs. Therefore, when replacing the brake pads, Lexus recommends that you
also have the thickness of the discs measured.
It is dangerous to drive the vehicle when the wear limits of the brake pads and/or
that of the brake discs are exceeded.
■If you get a flat tire while driving
A flat or damaged tire may cause the following situations. Hold the steering wheel
firmly and gradually press the brake pedal to slow down the vehicle.
●It may be difficult to control your vehicle.
●The vehicle will make abnormal sounds.
●The vehicle will behave abnormally.
Replace a flat tire with a new one. ( →P. 3 8 4 )
■When encountering flooded roads
Do not drive on a road that has flooded after heavy rain etc. Doing so may cause the
following serious damage to the vehicle.
●Engine stalling
●Short in electrical components
●Engine damage caused by water immersion
In the event that you drive on a flooded road and the vehicle is flooded, be sure to
have your Lexus dealer check the following.
●Brake function
●Changes in quantity and quality of oil and fluid used for the engine, transmission,
differential, etc.
●Lubricant condition for the propeller shaft, bearings and suspension joints (where
possible) and the function of all joints, bearings, etc.
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2-4. Using other driving systems
2
When driving
08_IS350/250_U_(L/O_0708)
CAUTION
■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.
Do not drive the vehicle in conditions where stability and power may be lost.
■If hill-start assist control does not operate effectively
(vehicles with an automatic transmission)
The hill-start assist control may not operate effectively on steep inclines and roads
covered in ice.
■When the VSC is activated
The slip indicator light flashes and a warning buzzer sounds. Always drive carefully.
Reckless driving may cause an accident. Exercise particular care when the indica-
tor light flashes and a buzzer sounds.
■When TRAC and VSC are off
Be especially careful and drive at a speed appropriate to the road conditions. As
there are systems to ensure vehicle stability and driving force, do not turn off TRAC
and VSC 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.
■Handling of tires and suspension
Using tires with any kind of problem or modifying the suspension will affect the driv-
ing assist systems, and may cause the system to malfunction.
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5-1. Essential information
08_IS350/250_U_(L/O_0708)
If you think something is wrong
If you notice any of the following symptoms, your vehicle probably needs
adjustment or repair. Contact your Lexus dealer as soon as possible.
■Visible symptoms
●Fluid leaks under the vehicle
(Water dripping from the air conditioning after use is normal.)
● Flat-looking tires or uneven tire wear
● Engine coolant temperature gauge needle continually points
higher than normal
■ Audible symptoms
●Changes in exhaust sound
● Excessive tire squeal when cornering
● Strange noises related to the suspension system
● Pinging or other noises related to the engine
■ Operational symptoms
●Engine missing, stumbling or running rough
● Appreciable loss of power
● Vehicle pulls heavily to one side when braking
● Vehicle pulls heavily to one side when driving on a level road
● Loss of brake effectiveness, sp ongy feeling, pedal almost touches
the floor