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

STARTING AND DRIVING
249
CRUISE CONTROL
The cruise control allows you to cruise the vehicle at a
desired speed over 40 km/h (25 mph) with your foot off the
accelerator pedal.
Your cruising speed can be maintained although a slight speed
change may occur when driving up or down a gradient, within
the limits of engine performance. On steeper hills, a great
speed change will occur so it is better to drive without the cruise
control.
When the cruise control is on, the driving pattern of the
automatic transmission is fixed in the normal position,
regardless of the position of the selector switch.
CAUTION
 To help maintain maximum control of your vehicle,
do not use the cruise control when driving in heavy
or varying traffic, or on slippery (rainy, icy or
snow±covered) or winding roads.
 Avoid vehicle speed increases when driving
downhill. If the vehicle speed is too fast in relation to
the cruise control set speed, cancel the cruise
control then downshift the transmission to use
engine braking to slow down.
Turning the system on
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To operate the cruise control, push the main switch. This turns
the system on. The indicator light in the instrument cluster
shows that you can now set your desired cruising speed.
Another push on the switch will turn the system completely off.
When the ignition key is turned off, the main switch is also
automatically turned off. To use the cruise control again, push
the main switch again to turn it on.
CAUTION
To avoid accidental cruise control engagement, keep
the main switch off when not using the cruise control.
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Setting operation
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Each function is described below.
1Setting at a desired speed.
Automatic transmission: The transmission must be in the
ªDº position or the gear position must be ª4º or ª5º in M mode
before you set the cruise control speed.
Bring the vehicle to the desired speed, press the control lever
downward in the ªSET/COASTº direction and release it. This
sets the vehicle at that speed. Now you may take your foot off
the accelerator pedal. If you need acceleration ± for example,
when passing ± depress the accelerator pedal enough for the
vehicle to exceed the set speed. When you release the
accelerator pedal, the vehicle will return to the speed set prior
to the acceleration.
2Cancelling the preset speed
You can cancel the preset speed by either of the following:
a. Pulling the control lever in the ªCANCELº direction.
b. Depressing the brake pedal.
c. Depressing the clutch pedal (manual transmission)
If the vehicle speed falls below about 40 km/h (25 mph), the
preset speed will be automatically cancelled.
If the vehicle speed drops 16 km/h (10 mph) below the preset
speed, the preset speed will also automatically be cancelled.
If the preset speed automatically cancels out for other than
these reasons, have your vehicle checked by your Lexus
dealer at the earliest opportunity.
3Resetting to a faster speed
Press the control lever upward in the ªRES/ACCº direction and
hold it. Release the lever when the desired speed is attained.
While the lever is held upward, the vehicle will gradually gain
speed.
When the difference between the actual vehicle speed and the
set speed is less than 5 km/h (3 mph), the set speed can be
increased 1.6 km/h (1 mph) each time by pressing the control
lever upward in the ªRES/ACCº direction quickly within 0.6
seconds.
However, a quicker way to reset is to accelerate the vehicle
and then press the control lever downward in the
ªSET/COASTº direction.
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STARTING AND DRIVING
251
4Resetting to a slower speed
Press the control lever downward in the ªSET/COASTº
direction and hold it. Release the lever when the desired speed
is attained. While the lever is held downward, the vehicle
speed will gradually decrease.
When the difference between the actual vehicle speed and the
set speed is less than 5 km/h (3 mph), the set speed can be
lowered 1.6 km/h (1 mph) each time by pressing the control
lever downward in the ªSET/COASTº direction quickly within
0.6 seconds.
However, a quicker way to reset is to depress the brake pedal
and then press the control lever downward in the
ªSET/COASTº direction.
Automatic transmission: Even if you downshift the
transmission from the ªDº position to ªMº with the cruise control
on, engine braking will not be applied because the cruise
control is not cancelled. To decrease the vehicle speed, reset
to a slower speed with the cruise control lever or depress the
brake pedal. If you use the brake pedal, cruise control is
cancelled.
5Resuming the preset speed
If the preset speed is cancelled by pulling the control lever or
by depressing the brake pedal, pushing the lever up in the
ªRES/ACCº direction will restore the speed set prior to
cancellation. However, once the vehicle speed falls below
about 40 km/h (25 mph), the preset speed will not be resumed.
Cruise control failure warning
If the ªCRUISEº indicator light in the instrument cluster flashes
five times and then goes out when using the cruise control, it
means that there is trouble in the cruise control system.
Contact your Lexus dealer.
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STARTING AND DRIVING
252
TRACTION CONTROL SYSTEM
(With vehicle stability control system)
The traction control system automatically helps prevent
the spinning of rear wheels when the vehicle is started or
accelerated on slippery road surfaces.
When the ignition key is turned to ªONº, the system
automatically turns on.
CAUTION
Under certain slippery road conditions, full traction of
the vehicle and power against rear wheels cannot be
maintained, even though the traction control system is
in operation. Do not drive the vehicle under any speed
or maneuvering conditions which may cause the
vehicle to lose traction control. In situations where the
road surface is covered with ice or snow, your vehicle
should be fitted with snow tires or tire chains. Always
drive at an appropriate and cautious speed for the
present road conditions.
Normal driving mode
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Slip indicator light
Leave the system on during the ordinary driving so that it
can operate when needed.
You may hear a sound in the engine compartment for a few
seconds just after the vehicle begins to move. This means that
the traction control system is in the self±check mode, but does
not indicate a malfunction.
When the traction control system is operating, the following
conditions occur:
 The system controls the spinning of the rear wheels. At this
time, the slip indicator light blinks.
 You may feel vibration or noise in your vehicle, caused by
operation of the brakes. This indicates the system is functioning properly.
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The ªTRAC OFFº indicator/warning light will come on when the
ªVSCº warning light comes on even if the ªTRAC OFFº switch
is not pushed.
TRACTION CONTROL SYSTEM
(Without vehicle stability control system)
The traction control system automatically helps prevent
the spinning of rear wheels when the vehicle is started or
accelerated on slippery road surfaces.
When the ignition key is turned to ªONº, the system
automatically turns on.
CAUTION
Under certain slippery road conditions, full traction of
the vehicle and power against rear wheels cannot be
maintained, even though the traction control system is
in operation. Do not drive the vehicle under any speed
or maneuvering conditions which may cause the
vehicle to lose traction control. In situations where the
road surface is covered with ice or snow, your vehicle
should be fitted with snow tires or tire chains. Always
drive at an appropriate and cautious speed for the
present road conditions.
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STARTING AND DRIVING
258
VEHICLE STABILITY CONTROLSYSTEM
The vehicle stability control system helps provide
comprehensive control of the systems such as anti±lock
brake system, traction control, engine control, etc. This
system automatically controls the brakes and engine to
help prevent the vehicle from skidding when cornering on
a slippery road surface or operating steering wheel
abruptly.
This system activates when the vehicle speed is about more
than 15 km/h (9 mph).
You may hear a sound in the engine compartment for a few
seconds just after the vehicle begins to move. This means that
the system is in the self±check mode, but does not indicate a
malfunction.
CAUTION
 Do not rely excessively on the vehicle stability
control system. Even if the vehicle stability control
system is operating, you must always drive carefully
and attentively to avoid serious injury. Reckless
driving will result in an unexpected accident. If the
slip indicator light blinks, sounding an alarm, special
care should be taken while driving.
 Only use tires of specified size. The size,
manufacture, brand and tread pattern for all 4 tires
should be the same. If you use the tires other than
specified, or different type or size, the vehicle
stability control system may not function correctly.
When replacing the tires or wheels, contact your
Lexus dealer.
 In situations where the road surface is covered with
ice or snow, your vehicle should be fitted with snow
tires or tire chains.
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STARTING AND DRIVING
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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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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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CAUTION
If the ªABSº warning light remains on together with the
brake system warning light, immediately stop your
vehicle at a safe place and contact your Lexus dealer.
In this case, not only the anti±lock brake system will fail
but also the vehicle will become extremely unstable
during braking.
Drum±in±disc type parking brake system
Your vehicle has a drum±in±disc type parking brake system.
This type of brake system needs bedding±down of the brake
shoes periodically or whenever the parking brake shoes
and/or drums are replaced.
Have your Lexus dealer perform the bedding±down.
Brake assist system
When you slam the brakes on, the brake assist system
judges as an emergency stop and provides more powerful
braking for a driver who cannot hold down the brake pedal
firmly.
When you slam the brakes on, more powerful braking will be
applied. At this time, you may hear a sound in the engine
compartment and feel the vibrations of the brake pedal. This
does not indicate a malfunction.
The brake assist 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).For an explanation of this system's warning light, see ªABSº
warning light on page 54 or 263.
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DRIVING TIPS
268
BREAK±IN PERIOD
Drive gently and avoid high speeds.
You need not follow a break±in schedule with your new Lexus.
But following a few simple tips for the first 1600 km (1000 miles)
can add to the future economy and long life of your vehicle:
Avoid full throttle acceleration when starting and driving.
 Avoid racing the engine.
 Try to avoid hard stops during the first 300 km (200 miles).
 Do not drive slowly with the manual transmission in a high
gear.
 Do not drive for a long time at any single speed, either fast
or slow.
OPERATION IN FOREIGN
COUNTRIES
If you plan to drive your Lexus in another country ...
First, comply with the vehicle registration laws.
Second, confirm the availability of the correct fuel (unleaded
and minimum octane rating).
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