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■If the cruise control indicator light flashes
Turn the ON-OFF button off once, and then reactivate the system.
If the cruise control speed cannot be set or if the cruise control cancels immediately
after being activated, there may be a malfunction in the cruise control system. Have
the vehicle inspected by your Lexus dealer.
CAUTION
■To avoid operating the cruise control by mistake
Keep the ON-OFF button off when not in use.
■Situations unsuitable for cruise control
Do not use cruise control in any of the following situations.
Doing so may result in control of the vehicle being lost and could cause serious or
fatal accident.
●In heavy traffic
●On roads with sharp bends
●On slippery roads, such as those covered with rain, ice or snow
●On steep hills
●On winding roads
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Dynamic laser cruise control (if equipped)
Dynamic laser cruise control supplements conventional cruise control
with a vehicle-to-vehicle distance co ntrol. In the vehicle-to-vehicle dis-
tance control mode, the vehicle automatically accelerates or decelerates
in order to maintain a set following distance from vehicles ahead.
■ Select cruise mode
Selecting vehicle-to-vehicle dis-
tance control modeTurn the ON-OFF button
ON.
Push the button once more to
deactivate.
Selecting conventional con-
stant speed control mode Turn the ON-OFF button
ON.
Push the button once more to
deactivate.
Vehicle-to-vehicle distance con-
trol mode is always reset when
the engine switch is turned to
the ON position.
Switch to constant speed
control mode.
(push and hold for approxi-
mately one second)
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■Driving in the selected cruise control mode
Accelerate or decelerate to the
desired speed and press the
lever down to set.
■ Adjusting the speed setting
Increase speed
Decrease speed
Hold the lever until the desired
speed setting is displayed.
■Canceling and resuming the speed setting
Cancel
Push the lever towards you to
cancel cruise control.
The setting is also canceled
when the brakes are applied.
Resume
To resume cruise control and
return to the set speed, push the
lever up.
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RX400h_UExample of follow-up cruising (when following a vehicle driving slower
than the set speed):
When the speed is set to 62 mph (100 km/h) and the vehicle ahead is
driving at 50 mph (80 km/h)
The system continues follow-up cruising while adjusting for changes in the
speed of the vehicle ahead in order to maintain the vehicle-to-vehicle dis-
tance set by the driver.
Example of acceleration (when there are no longer vehicles driving
slower than the set speed in the lane ahead):
When the speed is set to 62 mph (100 km/h) and the vehicle ahead
driving at 50 mph (80 km/h) is out of the lane
When the vehicle ahead of you executes a lane change, the system slowly
accelerates until the set vehicle speed is reached. The system then returns to
fixed speed cruising.
■Fine adjustment of the set speed
Adjustment of the set speed by the following speed can be made by lightly pressing
the lever up or down and releasing it.
In the constant speed control mode: Approximately 1.0 mph (1.6 km/h)
In the vehicle-to-vehicle distance control mode: U.S.A.: Approximately 5 mph (8 km/h)
Canada: Approximately 3 mph (5 km/h)
■Dynamic laser cruise control warning lights, display and buzzers
Warning lights, display and buzzers are used to indicate a system malfunction or to
alert you to the need for caution while driving. ( →P. 3 9 8 )
■The dynamic laser cruise can be set when
●The shift lever is in D.
●Vehicle speed is between approximately 27 mph (45 km/h) and 85 mph (135
km/h).
■Accelerating
The vehicle can be accelerated normally.
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■Vehicle-to-vehicle distance settings
Select a distance from the table below. Note that the distances shown correspond
to a vehicle speed of 55 mph (88 km/h). Vehicle-to-vehicle distance increases/
decreases in accordance with vehicle speed.
■Laser radar sensor
■Certification
Distance optionsVehicle-to-vehicle distance
LongApproximately 245 ft. (75 m)
MediumApproximately 165 ft. (50 m)
ShortApproximately 100 ft. (30 m)
Always keep the sensor clean to ensure that
the vehicle-to-vehicle distance control oper-
ates properly. (Some obstructions, such as
snow, ice or plastic objects, cannot be
detected by the obstruction sensor.)
Dynamic laser cruise control is canceled if an
obstruction is detected.
This product is a class I laser product complied with 21 C. F. R part 1040. 10. and
1040. 11.
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CAUTION
■Before using dynamic laser cruise control
Do not overly rely on vehicle-to-vehicle distance control.
Be aware of the set vehicle speed. If automatic deceleration/acceleration is not
appropriate, adjust the vehicle speed, as well as the distance between your vehicle
and vehicles ahead by applying the brakes, etc.
■To avoid inadvertent cruise control activation
Keep the ON-OFF button off when not in use.
■Situations unsuitable for dynamic laser cruise control
Do not use dynamic laser cruise control in any of the following situations.
Doing so may result in inappropriate control of speed and could cause serious or
fatal accident.
●In heavy traffic
●On roads with sharp bends
●On winding roads
●On slippery roads, such as those covered with rain, ice or snow
●Where there are sudden changes between sharp up and down gradients
●At entrances to expressways
●When weather conditions are bad enough that they may prevent the sensors
from functioning correctly (fog, snow, sandstorm, etc.)
●When buzzer can be heard often
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4-3. Do-it-yourself maintenance
RX400h_U
57RR FOG 7. 5No circuit
58AIR SUS7. 5No circuit
59DOOR NO.225Multiplex communication system
60S/ROOF 30Moon roof
61TA I L10
Front fog lights, instrument cluster
lights, instrument panel lights, front
side marker lights, tail lights, license
plate lights, towing converter
62PA N E L7. 5
Glove box light, instrument cluster
lights, instrument panel lights, console
box light, audio system, power outlet,
garage door opener switch, transmis-
sion system, headlight cleaner, seat
heaters, steering switches, power
back door
63ECU-IG NO.17. 5
Power rear view mirror control, moon
roof, multiplex communication system,
shift lock control system, multiplex
communication system (power door
lock system, wireless remote control
system), driving position memory sys-
tem, vehicle dynamics integrated
management, windshield wipers,
transmission, seat heaters, power
seats, tilt and telescopic steering,
power back door
64ECU-IG NO.210
Automatic headlight leveling system,
vehicle dynamics integrated manage-
ment, dynamic laser cruise control,
headlight cleaner, adaptive front-light-
ing system
FuseAmpereCircuit
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RX400h_U
(Flashing and then
continuously on)
Indicates a malfunction in the tire pressure warning
system. (→P. 3 3 2 )
(Flashing)
Malfunction in the traction control system or VSC
system.
(Flashing)
Indicates a malfunction in the dynamic laser cruise
control system.
Wa r n i n g m e s s a g eDetails