2005 LEXUS LS430 engine

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4Resetting to a slower speed
Press the control lever downward in the “– SET” direction and
hold it. The displayed speed will decrease in increments of 5
mph (for U.S.A.) or 5 km/h (for Canada). Release the lever
when the desired speed is attained. The vehicle will gradually
decrease to the displayed speed.
A quicker way to reset the preset speed is to depress the brake
pedal and then press the control lever downward in the “– SET”
direction.
If the control lever is released when the vehicle speed exceeds
the upper limit of the preset speed traveling downhill while you
are pressing the control leve r downward, the system will
memorize the upper limit of the preset speed as a preset
speed.
Even if you downshift the transmission from “D” or “6” (six\
th
range) to “5” (fifth range), or from “D” or “5” (f\
ifth range) to “4”
(fourth range) in the vehicle −to− vehicle distance control mode,
engine braking will not be enabled because this mode 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. 5 Resuming the preset speed
If the preset speed has been cancelled, when you push the
lever up in the “+ RES” direction while “RADAR READY”
shows up on the multi −information display and at a vehicle
speed of about more than 40 km/h (25 mph), the speed set
prior to cancellation will be restored.
During follow −up cruising, if there are no vehicles running
ahead because they have changed lanes, your vehicle will
accelerate gradually up to the preset speed.

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The vehicle
−to− vehicle distance is always set to “Long” when
the ignition switch is turned on.
CAUTION
 Select the vehicletovehicle distance
considering traffic conditions. The approximate
vehicletovehicle distance based on time
interval when driving at 88 km/h (55 mph) is
shown below :
“Long” about 75 m (about 245 ft.) . . . . . . . .
“Middle” about 50 m (about 165 ft.) . . . . . .
“Short” about 30 m (about 100 ft.) . . . . . . .
If the vehicle speed is slower than 88 km/h (55 mph),
the distance will be shorter than the above.
 During long downhill driving, the vehicletovehicle
distance will be shorter than the selected distance.
(e) Braking control
Dynamic radar/laser cruise control is not a collision avoidance
system. If an approach warning is activated, depress the brake
pedal to decelerate to ensure an appropriate
vehicle −to−vehicle distance.
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 1
Under the vehicletovehicle distance control
2Braking activated
Braking control is operating only when the vehicle −to− vehicle
distance control mode is selected and your vehicle speed
exceeds about 40 km/h (25 mph).
If you are getting closer to the vehicle ahead at relatively higher
speed than those of the vehicle ahead or if engine braking
cannot be applied properly, braking control is automatically
activated. The multi− information display changes as shown in
the illustration and the stop/tail lights on your vehicle and on the
vehicle on the display come on.

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Conventional (fixed speed) cruise control
mode
This mode allows you to cruise at a desired speed over
about 45 km/h (28 mph) with your foot off the accelerator
pedal.
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, the speed
will change more radically so it is better to drive without cruise
control.
When 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
 In the conventional (fixed speed) cruise control
mode, an approach warning does not activate even if
you are too close to the vehicle ahead, as neither the
presence of the vehicle ahead nor the
vehicletovehicle distance is detected. Pay special
attention to the distance between your vehicle and
the vehicle ahead. Always confirm the setting in the
multiinformation display.
 The conventional (fixed speed) cruise control mode
of the dynamic radar/laser cruise control should not
be used in the following conditions, which could
result in death or serious injury.
 To help maintain maximum control of your vehicle,
do not use fixed speed control mode when using
dynamic radar/laser cruise control while driving in
heavy or varying traffic, or on slippery (rainy, icy
or snowcovered) or winding roads.
 Avoid vehicle speed increasing when driving
downhill. If the vehicle speed is too fast in relation
to the preset speed in the fixed speed control
mode, cancel the fixed control mode and then
downshift the transmission to use engine braking
to slow down.

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4Resetting to a slower speed
Press the c ontrol lever downward in the “– SET” 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 “– SET” direction quickly within 0.6
seconds.
A quicker way to reset the preset speed is to depress the brake
pedal and then press the control lever downward in the “– SET”
direction.
Even if you downshift the transmission from the “D” or “6” (\
sixth
range) to “5” (fifth range), or from “D” or “5” (f\
ifth range) to “4”
(fourth range) in the conventional cruise control mode, engine
braking will not be applied because this mode is not cancelled.
To slow down, reset the cruise control to a slower speed with
the cruise control lever or depress the brake pedal. If you use
the brake pedal, cruise control is cancelled. 5 Resuming the preset speed
If the preset speed is cancelled by pulling the control lever, by
depressing the brake pedal or vehicle stability control
activation, pushing the lever up in the “+ RES” 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.
(c) Conventional cruise control mode failure warning
w281
If the system malfunction is detected when the
conventional cruise control mode is in the ready mode or
operating, the master warning light comes on, a warning
tone sounds and the above message appears.
If this message appears, push the “ON −OFF” button to turn the
system off and then push it again to turn it on. If the setting still
cannot be made or the same message appears again, the
system might have malfunctioned. Although it is no problem
to continue driving, contact your Lexus dealer.

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TRACTION 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 switch is turned to “ON”, 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.
31L138a
 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.
The slip indicator light comes on for a few seconds when the
ignition switch is turned to “ON”. If the indicator light does not
come on when the ignition is turned on, contact your Lexus
dealer.

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Traction control off mode
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If your wheels get stuck in a ditch when you are driving on
a severe off road and sand, turn off the traction control
system. This system that controls engine performance
interferes with the process of freeing your wheels.
To turn off: Push “TRAC OFF” switch.
The “TRAC OFF” indicator light will come on.
The vehicle stability control system is always activated even if
the traction control system is turned off.
To turn on: Push “TRAC OFF” switch once again.
The “TRAC OFF” indicator light will go off. “TRAC
OFF” indicator light comes on for a few seconds when
the ignition switch is turned to “ON”. It will come on again when
you push the “TRAC OFF” switch to turn off the system.
In the following cases, contact your Lexus dealer:
 The indicator light does not come on when the ignition
switch is turned to “ON”.
 The indicator light remains on after the ignition is turned on.
 The indicator light comes on in the normal driving mode
while driving.

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“Check VSC” warning message
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If the vehicle stability control system or the traction
control system malfunctions, the master warning light
and “TRAC OFF” indicator light come on. At this time a
warning tone sounds and the above message appears.
If the message appears, the vehicle stability control system
and traction control system do not work. Although it is no
problem to continue driving, have your vehicle checked by
your Lexus dealer as soon as possible.
VEHICLE STABILITY CONTROLSYSTEM
The vehicle stability control system helps provide
comprehensive control of the systems such as antilock
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.

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“Check VSC” warning message
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If the vehicle stability control system or the traction
control system malfunctions, the master warning light
and “TRAC OFF” indicator light come on. At this time a
warning tone sounds and the above message appears.
If the message appears, the vehicle stability control system
and traction control system do not work. Although it is no
problem to continue driving, have your vehicle checked by
your Lexus dealer as soon as possible.
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.