2006 Lexus GS430 cruise control

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398
CAUTION
Under certain conditions where the vehicle in front
slows drastically, or is stopped, the dynamic radar
cruise control will neither warn you nor decelerate. The
driver must depress the brake pedal to slow down,
ensuring collision avoidance or that sufficient
vehicletovehicle distance is maintained.
When vehicle−to−vehicle distance control mode is activated,
you must still be attentive to road and traf fic conditions. Should
your vehicle speed decrease below about 40 km/h (25 mph),
the dynamic radar cruise control will shut off, requiring you to
apply the brakes to slow. When a vehicle ahead slows
suddenly, stops or a vehicle cuts in front, the system may slow
your vehicle abruptly, but the automatic braking will cease if the
speed decreases below about 40 km/h (25 mph) requiring the
driver’s manual application of brakes.
CAUTION
Certain conditions make vehicle detection difficult or
impossible.
 As this system operates by detecting primarily the
reflected wave from the rear end of the vehicle ahead,
the distance cannot be accurately detected in the
following cases, resulting in improper
vehicletovehicle distance.
♦ The rear section of the vehicle ahead is extremely
small such as an unloaded trailer.
♦ The vehicle ahead or other vehicles around you
are flinging up water or snow.
♦ Heavy luggage which is loaded in your trunk or on
top of your rear seats is raising up the nose of your
vehicle.
 The millimeter wave radar sensor automatically
detects dirt if it is sticking to the front of the sensor
or cover of your vehicle, and if detected, a message
appears on the multiinformation display. However,
if the sensor or cover is covered with a metallic vinyl
bag, icicle, snowflakes, etc., dirt may not be detected,
resulting in improper vehicletovehicle distance.
Continue driving with due care to the vehicle ahead.
If dirt is detected, the dynamic radar cruise control
function is automatically cancelled. Always keep the
sensor and cover clean.

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Dynamic radar cruise control should not be used in the
following conditions, to avoid death or serious injury.
In bad weather (such as rain, fog, snow , sandstorms,
or when raindrops or snowflakes get in the millimeter
wave radar sensor or the cover), the
vehicletovehicle distance will not be measured
accurately.
If the wipers are operated at high speed (including the
high speed operation with the wiper lever in the
“AUTO” position), dynamic radar cruise control is
automatically cancelled. (In the case of the low speed
operation and intermittent wiper operation, it is not
cancelled.) Dynamic radar cruise control is
automatically cancelled when the measurement is
extremely unstable due to bad weather.
 On the roads in heavy traffic or at sharp bends:
As an appropriate speed cannot be maintained, death
or serious injury could result.
 On slippery road surfaces (icy or snowcovered road
surfaces):
The tires will race and you will be unable to control.On steep downhill slopes:
If there is no vehicle detected ahead, the preset speed
will be easily exceeded because of inefficient engine
braking, resulting in death or serious injury. (In this
case, automatic braking will not work.) If there is a
vehicle detected ahead, the delay in deceleration
timing could cause death or serious injury.
 When the warning tone sounds frequently (because
acceleration or deceleration was repeated or
sufficient vehicletovehicle distance was not
maintained), an appropriate vehicle speed cannot be
attained, resulting in death or serious injury.
 On roads with steep and short inclines and declines,
failure to detect the vehicle ahead will shorten the
distance between your vehicle and the vehicle ahead,
resulting in death or serious injury.

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G31013
Dynamic radar cruise control should not be used in
circumstances which are inappropriate for any cruise control
such as entering freeway on−ramps or off −ramps.
CAUTION
The dynamic radar cruise control should not be used
when exiting from, or when entering or merging onto a
freeway. When you are following a slower moving
vehicle and exiting, the sensor does not detect the
vehicle and will accelerate to preset speed.
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CAUTION
If other vehicles are driving outside of the millimeter
wave 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
cruise control system will not function properly.
 When a slower vehicle in front of you leaves the lane,
the dynamic radar cruise control will no longer detect
a vehicle ahead and will attempt to accelerate the
vehicle to the faster preset speed.

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(b) Turning the system on
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To operate the dynamic radar cruise control, push the
“ON−
OFF” button. This turns the system on. When the
“CRUISE” indicator light in the instrument cluster comes on
and “RADAR READY” appears on the multi−information
display, you can now set your desired cruising speed and
vehicle −to−vehicle distance. Pushing the “ON −OFF” button
again will turn the system completely off and “CRUISE OFF”
will appear on the multi −information display.
When the engine switch is turned off, the system is also
automatically turned off. To use the dynamic radar cruise
control again, push the “ON −OFF” button again to turn it on.
When the engine switch is turned off, all the preset data is
cleared. When you use the dynamic radar cruise control again,
you need to reset the data. The multi−
information display will return to the
vehicle −to−vehicle distance screen about 6 seconds after the
vehicle− to−vehicle distance screen has been changed to
another screen.
CAUTION
To avoid accidentally engaging the cruise control, keep
the “ONOFF” button off when not using the dynamic
radar cruise control.

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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. 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. At this time, the
multi−information display indicates settings such as the preset
vehicle speed, whether a vehicle is present ahead and
selected vehicle −to−vehicle distance. If there is no vehicle
detected ahead, the dynamic radar cruise control screen does
not display the vehicle ahead. 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
control 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 “CRUISE NOT
AVAILABLE”, “CLEAN RADAR SENSOR” or “CHECK
CRUISE SYSTEM”. If any of the above messages appears on
the display, see “Vehicle −to−vehicle distance control mode
failure warning” on page 410.
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. If no
warning message appears on the display, when you turn the
“ON−OFF” button on again, the setting can be made.
You can change the dynamic radar cruise control screen to
another screen even while the warning message is displayed.

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2Cancelling 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.
If cancelled by a. or b., the multi−information display shows
“RADAR READY” and the dynamic radar cruise control enters
the ready mode.
If cancelled by c., the “CRUISE” indicator light goes off in the
instrument cluster 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.
In the following case, the preset speed automatically
cancels out. At this time, the multiinformation display
shows “RADAR READY” and the dynamic radar 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 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 cruise control is restored, the warning
messages turn off and dynamic radar 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.
e. The wipers are operated at high speed (including high
speed operation with the wiper lever in the “AUTO” position.)
NOTICE
If the preset speed automatically cancels out for other
than the above reasons, do not operate the dynamic
radar cruise control. Although it is no problem to
continue driving, have your vehicle checked by your
Lexus dealer at the earliest opportunity.

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3Resetting to a faster speed
Press the control lever upward in the ”+ RES” direction and
hold it. The displayed speed will increase in increments of 5
mph (for the U.S.A.) or 5 km/h (for Canada). Release the lever
when the desired speed is attained. The vehicle will gradually
increase to the displayed speed.
Depressing the accelerator pedal and pressing the control
lever downward in the “– SET” direction will not reset to a faster
speed. At this time the set speed falls by 5 mph (for the U.S.A.)
or 5 km/h (for Canada).
CAUTION
When the vehicletovehicle distance control is on (on
followup cruising), your cruising speed is regulated in
proportion to the speed of the vehicle ahead, so
increasing the preset vehicle speed using the control
lever does not accelerate the vehicle. However, if the
vehicle ahead leaves the lane, your cruising speed will
increase up to the preset speed because the preset
speed has been set higher using the control lever.
Confirm the setting on the multiinformation display.
4 Resetting to a slower speed
Press the co ntrol lever downward in the “– SET” direction and
hold it. The displayed speed will decrease in increments of 5
mph (for the 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 lever 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.

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(e) Braking control
Dynamic radar 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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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. At this time, “BRAKE” flashes on the
multi−information display, indicating that the brakes are being
used.
CAUTION
Braking control will not ensure that your vehicle will
reduce speed appropriately. Do not rely on dynamic
radar cruise control to prevent collision.