wheel Lexus IS300 2005 Basic Functions / LEXUS 2005 IS300 (OM53489U) Service Manual

STARTING AND DRIVING
261
BRAKE SYSTEM
The tandem master cylinder brake system is a hydraulic
system with two separate sub±systems. If either sub±system
should fail, the other will still work. However, the pedal will be
harder to press, and your stopping distance will increase. Also,
the brake system warning light may come on.
CAUTION
Do not drive your vehicle with only a single brake
system. Have your brakes fixed immediately.
Brake booster
The brake booster uses engine vacuum to power±assist the
brakes. If the engine should quit while you are driving, you can
bring the vehicle to a stop with normal pedal pressure. There
is enough reserved vacuum for one or two stops but no more!
CAUTION
Do not pump the brake pedal if the engine stalls. Each
push on the pedal uses up your reserved vacuum.
 Even if the power assist is completely lost, the brakes
will still work. But you will have to push the pedal
hard, much harder than normal. And your braking
distance will increase.
Anti±lock brake system
The anti±lock brake system is designed to automatically
help prevent lock±up of the wheels during a sudden
braking or braking on slippery road surfaces. This assists
in providing directional stability and steering
performance of the vehicle under these circumstances.
Effective way to press the ABS brake pedal: When the
anti±lock brake system function is in action, you may feel the
brake pedal pulsating and hear a noise. In this situation, to
let the anti±lock brake system work for you, just hold the
brake pedal down more firmly. Do not pump the brake in a
panic stop. This will result in reduced braking performance.
The anti±lock brake system becomes operative after the
vehicle has accelerated to a speed in excess of approximately
10 km/h (6 mph). It stops operating when the vehicle
decelerates to a speed below approximately 5 km/h (3 mph).
Depressing the brake pedal on slippery road surfaces such as
on a manhole cover, a steel plate at a construction site, joints
in a bridge, etc. on a rainy day tends to activate the anti±lock
brake system.
You may hear a click or motor sound in the engine
compartment for a few seconds when the engine is started or
just after the vehicle begins to move. This means that the
anti±lock brake system is in the self±check mode, and does not
indicate a malfunction.
When the anti±lock brake system is activated, the
following conditions may occur. They do not indicate a
malfunction of the system:
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STARTING AND DRIVING
262
You may hear the anti±lock brake system operating and feel
the brake pedal pulsating and the vibrations of the vehicle
body and steering wheel. You may also hear the motor
sound in the engine compartment even after the vehicle is stopped.
 At the end of the anti±lock brake system activation, the
brake pedal may move a little forward.
CAUTION
Do not overestimate the anti±lock brake system:
Although the anti±lock brake system assists in
providing vehicle control, it is still important to drive
with all due care and maintain a moderate speed and
safe distance from the vehicle in front of you, because
there are limits to the vehicle stability and effectiveness
of steering wheel operation even with the anti±lock
brake system on.
If tire grip performance exceeds its capability, or if
hydroplaning occurs during high speed driving in the
rain, the anti±lock brake system does not provide
vehicle control.
Anti±lock brake system is not designed to shorten the
stopping distance: Always drive at a moderate speed
and maintain a safe distance from the vehicle in front of
you. Compared with vehicles without an anti±lock brake
system, your vehicle may require a longer stopping
distance in the following cases:
 Driving on rough, gravel or snow±covered roads.
 Driving with tire chains installed.
 Driving over the steps such as the joints on the road.
 Driving on roads where the road surface is pitted or
has other differences in surface height.
Install all 4 tires of specified size at appropriate
pressure: The anti±lock brake system detects vehicle
speeds using the speed sensors for respective wheels'
turning speeds. The use of tires other than specified
may fail to detect the accurate turning speed resulting
in a longer stopping distance.
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STARTING AND DRIVING
263
ªABSº warning light
SV31014

U.S.A.
SV31031

CANADA
The light comes on when the ignition key is turned to the ªONº
position. If the anti±lock brake system and the brake assist
work properly, the light turns off after a few seconds.
Thereafter, if either of the systems malfunctions, the light
comes on again.
When the ªABSº warning light is on (and the brake system
warning light is off), the anti±lock brake system, the brake
assist system, the traction control system and/or the vehicle
stability control system do not operate, but the brake system
still operates conventionally.
When the ªABSº warning light is on (and the brake system
warning light is off), the anti±lock brake system and/or the
traction
control system do/does not operate so that the wheels
could lock up during a sudden braking or braking on slippery
road surfaces.
If either of the following conditions occurs, this indicates
a malfunction somewhere in the components monitored
by the warning light system. Contact your Lexus dealer as
soon as possible to service the vehicle.
 The light does not come on when the ignition key is turned
to the ªONº position, or remains on.
 The light comes on while you are driving.
A warning light turning on briefly during operation does not
indicate a problem.
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STARTING AND DRIVING
265
BRAKE PAD WEAR INDICATORS
SS31030
The brake pad wear limit indicators on your disc brakes
give a warning noise when the brake pads are worn to the
extent that replacement is required.
If you hear a squealing or scraping noise while driving, have
the brake pads checked and replaced by your nearest Lexus
dealer immediately.
Avoid continuous driving with the warning noise.
Continuous driving without replacing the brake pads will cause
expensive rotor damage and increasing brake pedal effort to
get the same stopping distance.
LIMITED±SLIP DIFFERENTIAL
Some vehicles are equipped with a limited±slip differential. If
one rear wheel begins to spin, the limited±slip differential is
designed to aid traction by automatically transmitting driving
force to the other rear wheel. If you are not sure whether your
vehicle is equipped with one, you can ask your Lexus dealer.
CAUTION
Do not start or run the engine while your vehicle is
supported by a jack. The vehicle could be driven off the
jack and could pose a danger or result in serious injury.
NOTICE
Use only a spare tire of the same size, construction and
load capacity as the original tires on your Lexusbecause damage to the limited±slip differential couldpossibly occur with another tire type.
04 06.30

DRIVING TIPS
269
TIPS FOR DRIVING IN VARIOUSCONDITIONS
Always slow down in gusty crosswinds. This will allow you
much better control.
 Drive slowly onto curbs and, if possible, at a right angle.
Avoid driving onto high, sharp±edged objects and other
road hazards. Failure to do so can lead to severe tire damage such as a tire burst.
Drive slowly when passing over bumps or travelling on a
bumpy road. Otherwise, the impact could cause severe damage to the tires and/or wheels.
 When parking on a hill, turn the front wheels until they touch
the curb so that the vehicle will not roll. Apply the parking
brake, and place the transmission in ªPº (automatic) or in first or reverse (manual). If necessary, block the wheels.
 Washing your vehicle or driving through deep water may get
the brakes wet. To see whether they are wet, check that
there is no traffic near you and then press the pedal lightly.
If you do not feel a normal braking force, the brakes are
probably wet. To dry them, drive the vehicle cautiously while
lightly pressing the brake pedal with the parking brake
applied. If they still do not work safely, pull to the side of the road and call a Lexus dealer for assistance.
CAUTION
 Before driving off, make sure the parking brake is
fully released and that the parking brake reminder
light is off.
 Do not leave your vehicle unattended while the
engine is running.
 Do not rest your foot on the brake pedal while driving.
It can cause dangerous overheating, needless wear,
and poor fuel economy.
 To drive down a long or steep hill, reduce your speed
and downshift. Remember, if you ride the brakes
excessively, they may overheat and not work
properly. See page 243.
 Be careful when accelerating, upshifting,
downshifting or braking on a slippery surface. The
abrupt change in engine speed, such as sudden
acceleration or engine braking, could cause the
vehicle to skid or spin.
 Do not drive in excess of the speed limit. Even if the
legal speed limit permits it, do not drive over 140 km/h
(85 mph) unless your vehicle has high±speed
capability tires. Driving over 140 km/h (85 mph) may
result in tire failure, loss of control and possible
injury. Be sure to consult a tire dealer to determine
whether the tires on your vehicle are high±speed
capability tires or not before driving at such speeds.
04 06.30

DRIVING TIPS
271
Make sure the engine oil viscosity is suitable for the cold
weather.
See page 335 for recommended viscosity. Leaving a heavy
summer oil in your vehicle during winter months may cause
harder starting. If you are not sure about which oil to use, call
your Lexus dealer ± they will be pleased to help.
Check the electronic ignition system for loose
connections or obvious damage.
Keep the door locks from freezing.
Squirt
lock de±icer or glycerine into the locks to keep them from
freezing.
Use a washer fluid containing an antifreeze solution.
This product is available at your Lexus dealer and most auto
parts stores. Follow the manufacturer's directions for how
much to mix with water.
NOTICE
Do not use engine antifreeze or any other substitute
because it may damage your vehicle's paint.
Do not use your parking brake when there is a possibility
it could freeze.
When parking, put the transmission into ªPº (automatic) or into
first or reverse (manual) and block the front wheels. Do not use
the parking brake, or snow or water accumulated in and around
the parking brake mechanism may freeze the parking brake,
making it hard to release. Keep ice and snow from accumulating under the fenders.
Ice and snow built up under your fenders can make steering
difficult. During bad winter driving, stop and check under the
fenders occasionally.
Depending on where you are driving, we recommend you
carry some emergency equipment.
Some of
the things you might put in the vehicle are tire chains,
window scraper, bag of sand or salt, flares, small shovel,
jumper cables, etc.
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DRIVING TIPS
272
DINGHY TOWING
SV32002a
Your vehicle is not designed to be dinghy towed (with four
wheels on the ground) behind a motorhome.
NOTICE
Do not tow your vehicle with four wheels on the ground.This may cause serious damage to your vehicle.
TRAILER TOWING
SV32001
Lexus does not recommend towing a trailer with your
vehicle. It is not designed for trailer towing.
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DRIVING TIPS
273
HOW TO SAVE FUEL AND MAKEYOUR VEHICLE LAST LONGER
Improving fuel economy is easy ± just take it easy. It will help
make your vehicle last longer, too. Here are some specific tips
on how to save money on both fuel and repairs:
 Keep your tires inflated at the correct pressure. Check
the pressure every two weeks, or at least once a month. Underinflation causes tire wear and wastes fuel.
 Do not carry unneeded weight in your vehicle. Excess
weight puts a heavier load on the engine, causing greater
fuel consumption.
 Avoid lengthy warm±up idling. Once the engine is
running smoothly, begin driving ± but gently. Remember,
however, that on cold winter days this may take a little longer.
 Accelerate slowly and smoothly. Avoid jackrabbit starts.
 Avoid long engine idling. If you have a long wait and you
are not in traffic, it is better to turn off the engine and start again later.
 Avoid engine over±revving. Use a gear position suitable
for the road on which you are traveling.
 Avoid continuous speeding up and slowing down.
Stop±and±go driving wastes fuel. 
Avoid unnecessary stopping and braking. Maintain a
steady pace. Try to time the traffic signals so you only need
to stop as little as possible or take advantage of through
streets to avoid traffic lights. Keep a proper distance from
other vehicles to avoid sudden braking. This will also reduce wear on your brakes.
 Avoid heavy traffic or traffic jams whenever possible.
 Do not rest your foot on the brake pedal. This causes
premature wear, overheating and poor fuel economy.
 Maintain a moderate speed on highways. The faster you
drive, the greater the fuel consumption. By reducing your
speed, you will cut down on fuel consumption.
 Keep the front wheels in proper alignment. Avoid hitting
the curb and slow down on rough roads. Improper alignment
not only causes faster tire wear but also puts an extra load on the engine, which, in turn, wastes fuel.
 Keep the bottom of your vehicle free from mud, etc. This
not only lessens weight but also helps prevent corrosion.
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IN CASE OF AN EMERGENCY
286
IF YOU HAVE A FLAT TIRE
1. Reduce your speed gradually, keeping a straight line.
Move cautiously off the road to a safe place ± well away
from the traffic. Avoid stopping on the center divider of
a highway. Park on a level spot with firm ground.
2. Stop the engine and turn on your emergency flashers.
3. Firmly set the parking brake and put the transmission
in ªPº (automatic) or reverse (manual).
4. Have everyone get out of the vehicle on the side away
from traffic.
5. Read the following instructions thoroughly.
CAUTION
When jacking, be sure to observe the following to
reduce the possibility of personal injury:
 Follow jacking instructions.
 Do not put any part of your body under a vehicle
supported by a jack. Personal injury may occur.
 Do not start or run the engine while your vehicle
is supported by the jack.
Stop the vehicle on a level firm ground, firmly
set the parking brake and put the transmission
in ªPº (automatic) or reverse (manual). Block
the wheel diagonally opposite to the one being
changed if necessary.
 Make sure to set the jack properly in the jack
point. Raising the vehicle with jack improperly
positioned will damage the vehicle or may allow
the vehicle to fall off the jack and cause
personal injury.
 Never get under the vehicle when the vehicle is
supported by the jack alone.
 Use the jack only for lifting your vehicle during
wheel changing.
 Do not raise the vehicle with someone in the
vehicle.
 When raising the vehicle, do not put an object
on or under the jack.
 Raise the vehicle only high enough to remove
and change the tire.
NOTICE
Do not continue driving with a deflated tire.
Driving even a short distance can damage a tire
and wheel beyond repair.
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IN CASE OF AN EMERGENCY
287
Compact spare tire (Some models)
SV64025
The compact spare tire is designed for temporary
emergency use only.
The compact spare tire is identified by the distinctive
wording ªTEMPORARY USE ONLYº molded into the
sidewall of the tire.
To keep the compact spare tire noticeable, do not hide
the wheel by a wheel cover or such.
The compact spare tire saves space in your luggage
compartment, and its lighter weight helps to improve fuel
economy and permits easier installation in case of a flat
tire. The compact spare tire can be used many times, if
necessary. It has tread life of up to 4800 km (3000 miles)
depending on road conditions and your driving habits.
When tread wear indicators appear on the tire, replace
the tire. (See ªChecking and replacing tiresº on page
368.)
CAUTION

The compact spare tire was designed especially
for your Lexus. Do not use it on any other
vehicle.
 Do not use more than one compact spare tire at
the same time.
 The pressure for the compact spare tire must be
420 Kpa (4.2 kgf/cm
2
or bar, 60 psi).
 Do not exceed 80 km/h (50 mph) when driving
with the compact spare tire.
 Replace the compact spare tire with the
standard tire as soon as possible.
 Avoid sudden acceleration, sudden
deceleration and sharp turns with the compact
spare tire.
04 06.30