sensor LEXUS RX400H 2008 User Guide

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2-3. Operating the lights and windshield wipers
RX400h_U
■Rain drop sensor (vehicles with the rain-sensing windshield wipers)
■If no windshield washer fluid sprays
Check that the washer nozzles are not blocked if there is washer fluid in the wind-
shield washer fluid reservoir.
■Customization that can be configured at Lexus dealer
The setting of the wiper operation when the vehicle is stationary can be changed.
(Customizable features →P. 4 5 8 )
CAUTION
■Caution regarding the use of windshield wipers in AUTO mode
The windshield wipers may operate unexpectedly if the sensor is touched or the
windshield is subject to vibration in AUTO mode. Take care that your fingers or any-
thing else do not become caught in the windshield wipers.
NOTICE
■When the windshield is dry
Do not use the wipers, as they may damage the windshield.
■When there is no washer fluid spray from the nozzle
Damage to the washer fluid pump may be caused if the lever is pulled toward you
and held continually.
The sensor judges the amount of raindrops.

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2-4. Using other driving systems
2
When driving
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Driving in vehicle-to-vehicle distance control mode
This mode employs a laser radar sensor to detect the presence of vehi-
cles within 400 ft. (120 m) ahead and to judge the distance between your
vehicle and those vehicles.
Note that vehicle-to-vehicle distance will close when traveling on long
downhill slopes.
Example of constant speed cruising (when there are no vehicles
ahead):
When set to 62 mph (100 km/h)
The vehicle travels at the speed set by the driver. The desired vehicle-to-vehi-
cle distance can also be set by operating the vehicle-to-vehicle distance
switch.
Example of deceleration cruising (when the vehicle ahead is driving
slower than the set speed):
When fixed speed cruising is set at 62 mph (100 km/h) and the vehicle
ahead is driving at 50 mph (80 km/h)
When a vehicle is detected running ahead of you, in the same lane, the sys-
tem automatically decelerates your vehicle. When a greater reduction in
vehicle speed is necessary, the system applies the brakes. A warning tone
warns you when the system cannot decelerate sufficiently to prevent your
vehicle from closing on the vehicle ahead.

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2-4. Using other driving systems
2
When driving
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■Automatically canceling vehicle-to-vehicle distance control
Vehicle-to-vehicle distance control driving is automatically canceled in the follow-
ing situations.
●Vehicle speed falls below 25 mph (40 km/h)
●VSC is activated
●The sensor cannot operate correctly because it is covered in some way.*
●The windshield wipers are operating at high or low speed.*
*
: Vehicle-to-vehicle distance control driving must be reset by turning the ON-OFF button on again.
If vehicle-to-vehicle distance control driving is automatically canceled for any other
reason, there may be a malfunction in the system. Contact your Lexus dealer.
■Automatically cancelling constant speed control
The set speed is automatically canceled in the following situations.
●Actual vehicle speed is more than 10 mph (16 km/h) below the preset vehicle
speed
At this time, the memorized set speed is not retained.
●Vehicle speed falls below 25 mph (40 km/h)
●VSC is activated

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2-4. Using other driving systems
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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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2-4. Using other driving systems
2
When driving
RX400h_U
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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2-4. Using other driving systems
RX400h_U
CAUTION
■When the laser radar sensor may not be correctly detecting the vehicle ahead
Apply the brakes as necessary when any of the following types of vehicles are in
front of you.
As the sensor may not be able to correctly detect these types of vehicles, the prox-
imity alarm (→P. 164) will not be activated, and an accident may result.
●Vehicles that cut in suddenly
●Vehicles traveling at low speeds
●Vehicles that are not moving
●Vehicles with small rear ends (trailers with no load on board etc.)
●Motorcycles traveling in the same lane
■Conditions under which the vehicle-to-vehicle distance control may not function
correctly
Apply the brakes as necessary in the following conditions as the laser radar sensor
may not be able to correctly detect vehicles ahead, and an accident may result.
●When water or snow thrown up by the surrounding vehicles hinders the function-
ing of the sensor
●When your vehicle is pointing upwards (caused by a heavy load in the luggage
compartment, etc.)
●When the road curves or when the lanes are narrow
●When steering wheel operation or your position in the lane is unstable
■To ensure the laser radar sensor functions correctly
Do not do the following to the sensor as doing so may cause the sensor not to func-
tion correctly and could result in an accident.
●Stick or attach anything to them
●Leave them dirty
●Disassemble, subject them to strong shocks
●Modify or paint them
●Replace them with non-genuine parts

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2-5. Driving information
RX400h_U
NOTICE
■Repairing or replacing snow tires
Request repairs of and obtain replacement snow tires from Lexus dealers or legiti-
mate tire retailers.
This is because the removal and attachment of snow tires affects the operation of
the tire air pressure sensor.
■Fitting tire chains
The tire air pressure sensor may not function correctly when tire chains are fitted.

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3-6. Other interior features
3
Interior features
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CAUTION
■While driving the vehicle
Do not adjust the display. Be sure to adjust the display only when the vehicle is
stopped.
■When doing the circling calibration
Be sure to secure a wide space, and watch out for people and vehicles in the neigh-
borhood. Do not violate any local traffic rules while performing circling calibration.
NOTICE
■To avoid the compass malfunctions
Do not place magnets or any metal objects near the inside rear view mirror.
Doing this may cause a malfunction of the compass sensor.
■To ensure normal operation of the compass
●Do not perform circling calibration of the compass in a place where the earth's
magnetic field is subject to interference by artificial magnetic fields.
●During calibration, do not operate electric systems (moon roof, power windows,
etc.) as they may interfere with the calibration.

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5-1. Essential information
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Event data recorder
In a crash or a near car crash eventThe SRS airbag sensor assembly contains the EDR. In a crash or a near
car crash event, this device may record some or all of the following infor-
mation:
● Gasoline engine speed
● Whether the brake pedal was applied or not
● Ve h i c l e s p e e d
● To what extent the accelerator pedal was depressed
● Position of the transmission shift lever
● Whether the driver and front passenger wore seat belts or not
● Driver's seat position
● SRS airbag deployment data
● SRS airbag system diagnostic data
● Front passenger’s occupant classification
The information above is intended to be used for the purpose of improv-
ing vehicle safety performance. Unlike general data recorders, the EDR
does not record sound data such as conversation between passengers.
Your vehicle has computers that monitor and control certain aspects of
your vehicle. These computers assist in driving and maintaining optimal
vehicle performance.
Besides storing data useful for troubleshooting, there is an event data
recorder (EDR) that records data in a crash or a near car crash event.

5
When trouble arises
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5-2. Steps to take in an emergency
RX400h_U
■Key reminder buzzer
The buzzer indicates that the key has not been removed from the engine switch
(with the engine switch in the ACC or LOCK position and the driver’s door
opened).
■If the malfunction indicator lamp comes on while driving
First check the following:
●Is your vehicle low on gas?
If it is, refuel the vehicle immediately.
●Is the fuel tank cap loose?
If it is, tighten it securely.
The lamp will go off after taking several driving trips.
If the light does not go off even after several trips, contact your Lexus dealer as soon
as possible.
■Front passenger detection sensor and passenger seat belt reminder
●If luggage is placed on the front passenger seat, the front passenger detection
sensor may cause the warning light to flash, even if a passenger is not sitting in the
seat.
●If a cushion is placed on the seat, the sensor may not detect a passenger, and the
warning light may not operate properly.
■Changing the engine oil (U.S.A. only)
Make sure to reset the oil change system. ( →P. 3 2 1 )
■When the tire pressure warning light comes on
Check the tire inflation pressure and adjust to the appropriate level. Pushing the tire
pressure warning reset switch does not turn off the tire pressure warning light.
■The tire pressure warning light may turn on due to natural causes
The tire pressure warning light may turn on due to natural causes such as natural air
leaks or tire inflation pressure changes caused by temperature. In this case, adjust-
ing the tire inflation pressure will turn off the warning light (after a few minutes).