brake LEXUS LS430 2005 Owner's Guide

STARTING AND DRIVING
342In the following case, the preset speed automatically
cancels out. At this time, the multiinformation display
shows “RADAR READY” and the dynamic radar/laser
cruise control enters the ready mode.
The vehicle speed falls below about 40 km/h (25 mph). (40
km/h (25 mph) is designated as a cancel speed.)
CAUTION
In this case, the warning tone reminds you that the
dynamic
radar/laser cruise control is cancelled and you
must apply the brakes to slow the vehicle.
In the following cases, the warning messages appear and
the preset speed automatically cancels out. When
dynamic radar/laser cruise control is restored, the
warning messages turn off and dynamic radar/laser
cruise control enters “RADAR READY” mode.
a. The slip indicator light blinks and a warning tone sounds.
(This occurs when the vehicle is about to skid.)
b. The driving pattern selector switch is set to “SNOW” mode.
c. The anti −lock brake system is activated by automatic
braking. (The warning tone sounds.)
d. The sensor does not operate properly because a foreign
matter sticks to the sensor.
Dynamic radar cruise control—
e. The wipers are operated at high speed (including high
speed operation with the wiper lever in the “AUTO” position.)
Dynamic laser cruise control—
f. The wipers are operated at high or low speeds (including
high and low speed operations with the wiper lever in the
“AUTO” position.)

STARTING AND DRIVING
344
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.

STARTING AND DRIVING
345
CAUTION
Deceleration cruising function and approach
warning do not operate when the vehicle ahead is at
a stop or driving very slowly
 While vehicletovehicle distance control (followup
cruising) is on, acceleration and deceleration are
automatically performed in proportion to the speed
of the vehicle ahead detected. However, if the vehicle
ahead of you decelerates abruptly or if another
vehicle cuts in ahead of you, your vehicle may collide
with the vehicle ahead unless you manually depress
the brake pedal to slow down your vehicle. If you
need to accelerate because the vehicle ahead or you
changes lanes, then depress the acceleration pedal.
 Depending on the road configuration (curved roads,
left and right continuous curved roads, driving at the
start or end of the curve, narrow driving lanes due to
road construction) or your vehicle condition
(steering wheel maneuvering, position in the lane or
unstable driving because of an accident or
breakdown), vehicles in other lanes or surrounding
objects will be detected, resulting in a control failure
or the activated approach warning. This may also
result in a very close distance between vehicles due
to a failure to detect the vehicle ahead. Maneuvering
the steering wheel in response to a violent lateral
wind will cause similar conditions.
31L588
CAUTION
If other vehicles are driving outside of the millimeter
wave radar or laser radar detection range, a delay in the
detection of the vehicle cutting in at short range or
detection failure of the motorcycle running on the side
of the same lane will occur. In this case, the dynamic
radar/laser cruise control system will not function
properly.

STARTING AND DRIVING
347
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.
31L177
 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.

STARTING AND DRIVING
348
CAUTION
Braking control will not ensure that your vehicle will
reduce speed appropriately. Do not rely on dynamic
radar/laser cruise control to prevent collision.
(f) Approach warning
31L332
CAUTION
While you are cruising in the vehicletovehicle
distance control mode, if the vehicle ahead decelerates
abruptly or if another vehicle cuts in ahead of you,
inadequate braking will make your vehicle closer to the
vehicle ahead of you and the multiinformation display
flashes and beeps. The driver must depress the brake
pedal to slow down, ensuring collision avoidance or
that sufficient vehicletovehicle distance is
maintained.

STARTING AND DRIVING
357
(b) Setting operation
31L637
Each function is described below.
1
Setting the desired speed
The transmission must be in “D”, “6” (sixth range), “5”\
(fifth
range) or “4” (fourth range) before you set the cruise control
speed in the conventional cruise control mode of the dynamic
radar/laser cruise control.
After bringing the vehicle to the desired speed, press the
control lever downward in the “– SET” direction and release it.
This sets the vehicle at that speed and the multi −information
display shows the preset speed. At this time, you may take
your foot off the accelerator pedal. If you need to accelerate
− for example, when passing − depress the accelerator pedal
enough for the vehicle to exceed the preset speed. When you
release the accelerator pedal, the vehicle will return to the
speed set prior to acceleration. You cannot set a desired speed if the master warning light
comes
on, the warning tone sounds and the multi− information
display indicates a warning message such as “Check Cruise
System”. If this messages appears on the display, see
“Conventional cruise control mode failure warning” on page
359.
If you turn off the “ON−OFF” button while the warning message
is displayed, the warning message turns off and the
multi−information display switches to another screen. When
you turn the “ON −OFF” button on again, the warning message
comes back on the display. If no warning message appears on
the display, the setting can be made.
You can change the dynamic radar/laser cruise control screen
to another screen even while the warning message is
displayed.
2 Cancelling the preset speed
You can cancel the preset speed by doing any of the following:
a. Pulling the control lever in the ”CANCEL” direction.
b. Depressing the brake pedal.
c. Pushing the “ON −OFF” button at the end of the cruise
control lever.
If cancelled by a. or b., the multi −information displays shows
nothing and the conventional cruise control enters the ready
mode.
If cancelled by c., the “CRUISE” indicator light goes off in the
instrument panel and the multi −information display shows
“CRUISE OFF”. In this case, the preset speed data is cleared,
and you must set the speed from the beginning.

STARTING AND DRIVING
359
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.

STARTING AND DRIVING
362
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.

STARTING AND DRIVING
364
“Check VSC” warning message
31L337a
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.

STARTING AND DRIVING
366
“Check VSC” warning message
31L337a
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.