low LEXUS RX450H 2019 Owners Manual

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■Automatic cancelation of constant speed control mode
Constant speed control mode is automatica lly canceled in the following situations:
●Actual vehicle speed is more than approxim ately 10 mph (16 km/h) below the set vehi-
cle speed.
●Actual vehicle speed falls below approximately 25 mph (40 km/h).
●VSC is activated.
●TRAC is activated for a period of time.
●When the VSC or TRAC system is turned off.
●Pre-collision braking is activated.
If constant speed control mode is automati cally canceled for any other reason, there may
be a malfunction in the system . Contact your Lexus dealer.
■Warning messages and buzzers for dynamic radar cruise control with full-speed range
Warning messages and buzzers are used to indicate a system malfunction or to inform
the driver of the need for ca ution while driving. If a warning message is shown on the
multi-information display, read the message and follow the instructions.
■When the sensor may not be correctly detecting the vehicle ahead
In the case of the following and depending on the conditions, operate the brake pedal
when deceleration of the system is insuff icient or operate the accelerator pedal when
acceleration is required.
As the sensor may not be able to correctly detect these types of vehicles, the approach
warning ( P. 314) may not be activated.
●Vehicles that cut in suddenly
●Vehicles traveling at low speeds
●Vehicles that are not moving in the same lane
●Vehicles with small rear ends (traile rs with no load on board, etc.)

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●Motorcycles travelin g in the same lane
●When water or snow thrown up by the surrounding vehicles hinders the detecting of
the sensor
■Conditions under which the ve hicle-to-vehicle distance control mode may not function
correctly
In the case of the following conditions, o perate the brake pedal (or accelerator pedal,
depending on the situ ation) as necessary.
As the sensor may not be able to correctly detect vehicles ahead, the system may not
operate properly.
●When the vehicle ahead of you decelerates suddenly
●When your vehicle is pointing upwards
(caused by a heavy load in the luggage com-
partment, etc.)
●Preceding vehicle has an extremely high
ground clearance
●When the road curves or when the lanes are
narrow
●When steering wheel operation or your posi-
tion in the lane is unstable

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Press “” or “ ” of the meter control switches, select .
Press “ ” or “ ” of the meter control switches, select “BSM”.
Press “ ” or “ ” of the meter control switch es, select “BSM” or “RCTA”.
■Outside rear view mirror indicator visibility
In strong sunlight, the outside rear view mirror indicator may be difficult to see.
■Hearing the RCTA buzzer
The RCTA buzzer may be difficult to hear over loud noises, such as if the audio system
volume is high.
■When there is a malfunction in the Blind Spot Monitor
If a system malfunction is detected due to any of the following, a warning message will be
displayed: ( P. 667)
●A sensor is malfunctioning
●A sensor is dirty or covere d with snow or a sticker
●The outside temperature is extremely high or low
●Sensor voltage is abnormal
●A sensor is misaligned
■Certification for the Blind Spot Monitor
For vehicles sold in the U.S.A.
For vehicles sold in Canada
Turning the BSM function/RCTA function on/off
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■Customization
Some functions can be customized. ( P. 331, 667)
WARNING
■Handling the radar sensor
Blind Spot Monitor sensors ar e installed behind the left and right sides of the rear
bumper respectively. Observe the following to ensure the Blind Spot Monitor can
function correctly.
●Do not subject a sensor or its surrounding area on the rear bumper to a strong
impact.
If a sensor is moved even slightly off po sition, the system may malfunction and vehi-
cles may not be detected correctly.
In the following situations , have your vehicle inspected by your Lexus dealer.
• A sensor or its surrounding area is subject to a strong impact.
• If the surrounding area of a sensor is sc ratched or dented, or part of them has
become disconnected.
●Do not disassemble the sensor.
●Do not attach stickers to the sensor or surrounding area on the rear bumper.
●Do not modify the sensor or surrounding area on the rear bumper.
●Do not paint the rear bumper any colo r other than an official Lexus color.
●Keep the sensors and the surrounding areas
on the rear bumper clean at all times.
If a sensor or its surrounding area on the rear
bumper is dirty or covered with snow, the
Blind Spot Monitor may not operate and a
warning message (P. 667) will be dis-
played. In this situation, clear off the dirt or
snow and drive the vehicle with the operation
conditions of the BSM function ( P. 325)
satisfied for approximately 10 minutes. If the
warning message does not disappear, have
the vehicle inspected by your Lexus dealer.

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The BSM function uses radar sensors to detect the following vehicles traveling in
adjacent lanes and advises th e driver of the presence of such vehicles via the
indicators on the outside rear view mirrors.
Vehicles that are traveling in areas th at are not visible using the outside rear
view mirrors (the blind spots)
Vehicles that are approaching rapidly from behind in areas that are not visible
using the outside rear view mirrors (the blind spots)
BSM function
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The areas that vehicles can be detected in are outlined below.
The range of each detection area is: Approximately 1.6 ft. (0.5 m) to 11.5 ft. (3 .5 m) from either side of the vehicle
*
*
: The area between the side of the vehicle and 1.6 ft. (0.5 m) from the side of the vehicle
cannot be detected.
Approximately 3.3 ft. (1 m) forward of the rear bumper
Approximately 9.8 ft. (3 m) from the rear bumper
Approximately 9.8 ft. (3 m) to 197 ft. (60 m) from the rear bumper
*
*
: The greater the difference in speed betwee n your vehicle and the detected vehicle is,
the farther away the vehicle will be detect ed, causing the outside rear view mirror
indicator to illuminate or flash.
BSM function detection areas
WARNING
■Cautions regarding the use of the function
The driver is solely responsible for safe driving. Always drive safely, taking care to
observe your surroundings.
The BSM function is a supplementary function which alerts the driver that a vehicle is in
a blind spot of the outside rear view mirrors or is approaching rapidly from behind into
a blind spot. Do not overly rely on the BSM function. As the function cannot judge if it is
safe to change lanes, over reliance could lead to an accident resulting in death or seri-
ous injury.
As the system may not function correctly under certain conditions, the driver’s own
visual confirmation of safety is necessary.
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■The BSM function is operational when
The BSM function is operational when all of the following conditions are met:
●The BSM function is on.
●The shift lever is in a position other than R.
●The vehicle speed is greater than approximately 10 mph (16 km/h).
■The BSM function will detect a vehicle when
The BSM function will detect a vehicle present in the dete ction area in the following situ-
ations:
●A vehicle in an adjacent la ne overtakes your vehicle.
●Another vehicle enters the detection area when it changes lanes.
■Conditions under which the BSM function will not detect a vehicle
The BSM function is not designed to detect the following types of vehicles and/or
objects:
●Small motorcycles, bicycles, pedestrians, etc.*
●Vehicles traveling in the opposite direction
●Guardrails, walls, signs, parked vehi cles and similar stationary objects*
●Following vehicles that are in the same lane*
●Vehicles traveling 2 lanes away from your vehicle*
*
: Depending on the conditions, detection of a vehicle and/or object may occur.

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■Conditions under which the BSM function may not function correctly
●The BSM function may not detect vehicles correctly in the following situations:
• When the sensor is misaligned due to a stro ng impact to the sensor or its surround-
ing area
• When mud, snow, ice, a sticke r, etc. is covering the sensor or surrounding area on
the rear bumper
• When driving on a road surf ace that is wet with standing water during bad weather,
such as heavy rain, snow, or fog
• When multiple vehicles are approaching wi th only a small gap between each vehicle
• When the distance between your vehicle and a following vehicle is short
• When there is a significant difference in speed between your vehicle and the vehicle that enters the detection area
• When the difference in speed between your vehicle and another vehicle is changing
• When a vehicle enters a detection area traveling at about the same speed as your vehicle
• As your vehicle starts from a stop, a vehicle remains in the detection area
• When driving up and down cons ecutive steep inclines, such as hills, dips on the road,
etc.
• When driving on roads with sharp bends, consecutive curves, or uneven surfaces
• When vehicle lanes are wide, or when driving on the edge of a lane, and the vehicle in an adjacent lane is far away from your vehicle
• When towing a trailer (vehicles with towing package)
• When items such as a bicycle carrier are installed on the rear of the vehicle
• When there is a significant difference in height between your vehicle and the vehicle that enters the detection area
• Immediately after the BSM function is turned on
●Instances of the BSM function unnecessarily detecting a vehicle and/or object may
increase in the following situations:
• When the sensor is misaligned due to a stro ng impact to the sensor or its surround-
ing area
• When the distance between your vehicle and a guardrail, wall, etc. that enters the detection area is short
• When driving up and down cons ecutive steep inclines, such as hills, dips on the road,
etc.
• When vehicle lanes are narrow, or when driv ing on the edge of a lane, and a vehicle
traveling in a lane other than the ad jacent lanes enters the detection area
• When driving on roads with sharp bends, consecutive curves, or uneven surfaces
• When the tires are slipping or spinning
• When the distance between your vehicle and a following vehicle is short
• When a bicycle carrier or other accessory is installed to the rear of the vehicle
• When towing a trailer (vehicles with towing package)

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■RCTA icon display
When a vehicle approaching from the right or left at the rear of the vehicle is
detected, the following will be displayed on the audio system screen.
DisplayContent
A vehicle is approaching from the left at the rear of the vehicle
A vehicle is approaching from the right at the rear of the vehicle
Vehicles are approaching from both sides of the vehicle
The RCTA function is malfunctioning
( P. 321)
WARNING
■Cautions regarding the use of the function
The driver is solely responsible for safe driving. Always drive safely, taking care to
observe your surroundings.
The RCTA function is only a supplementary function which alerts the driver that a vehi-
cle is approaching from the right or left at the rear of the vehicle. As the RCTA function
may not function correctly under certain cond itions, the driver’s own visual confirma-
tion of safety is necessary. Over reliance on this function may lead to an accident
resulting death or serious injury.

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The areas that vehicles can be detected in are outlined below.
The buzzer can alert the driver of faster vehicles approaching from farther away.
Example:
■The RCTA function is operational when
The RCTA function operates when all of the following conditions are met:
●The RCTA function is on.
●The shift lever is in R.
●The vehicle speed is less than approximately 5 mph (8 km/h).
●The approaching vehicle speed is between approximately 5 mph (8 km/h) and 18 mph
(28 km/h).
RCTA function detection areas
Approaching vehicleSpeedApproximate
alert distance
Fast18 mph (28 km/h)65 ft. (20 m)
Slow5 mph (8 km/h)18 ft. (5.5 m)
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