2018 LEXUS RX450h warning light

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If the PCS warning light flas hes or illuminates and a warning message is displayed on
the multi-inform ation display
The pre-collision system may be temporarily unavailable or there may be a malfunction
in the system. ●
In the following situations, the warning light will turn off, the message will disappear and
the system will become operational when normal operating conditions return:
• When the radar sensor or ca mera sensor or the area around either sensor is hot,
such as in the sun
• When the radar sensor or camera sensor or the area around either sensor is cold,
such as in an extremely cold environment
• When a front sensor is dirt y or covered with snow, etc.
• When the part of the windshield in front of the camera sensor is fogged up or cov-
ered with condensation or ice (Defogging the windshield: → P. 516)
• If the camera sensor is obstructed, such as when the hood is open or a sticker is
attached to the windshield near the camera sensor ●
If the PCS warning light continues to flash or remains illuminated or the warning mes-
sage does not disappear even though the vehicle has returned to normal, the system
may be malfunctioning. Have the vehicle in spected by your Lexus dealer immediately.■
If VSC is disabled ●
If VSC is disabled ( → P. 385), the pre-collision brake assist and pre-collision braking
functions are also disabled. ●
The PCS warning light will turn on and “V SC Turned Off Pre-Collision Brake System
Unavailable” will be displayed on the multi-information display.

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Before using LKA system
Do not rely solely upon the LKA system. LKA is not a system which automatically
drives the vehicle or reduces the amount of attention that must be paid to the area in
front of the vehicle. The driver must always assume full responsibility for driving safely
by always paying careful attention to the surrounding conditions and operate the steer-
ing wheel to correct the path of the vehicle. Also, make sure to take adequate breaks
when fatigued, such as from driv ing for a long period of time.
Failure to perform appropriate driving operat ions and pay careful attention may lead to
an accident, resulting in death or serious injury. ■
To avoid operating LKA by mistake
When not using the LKA system, use the LKA switch to turn the system off. ■
Situations unsuitable for LKA
Do not use the LKA system in the following situations.
The system may not operate properly and lead to an accident, resulting in death or
serious injury. ●
A spare tire, tire chains, etc., are equipped. ●
When the tires have been excessively worn, or when the tire inflation pressure is low. ●
Tires which differ by structure, manufacturer, brand or tread pattern are used. ●
Objects or patterns that could be mistaken for white (yellow) lines are present on the
side of the road (guardrails, cu rbs, reflective poles, etc.).●
Vehicle is driven on a snow-covered road. ●
White (yellow) lines are difficult to see due to rain, snow, fog, dust, etc.●
Asphalt repair marks, white (y ellow) line marks, etc., are present due to road repair.●
Vehicle is driven in a temporary lane or restricted lane due to construction work.●
Vehicle is driven on a road surface which is slippery due to rainy weather, fallen snow,
freezing, etc. ●
Vehicle is driven in traffic lanes ot her than on highways and freeways.●
Vehicle is driven in a construction zone. ●
When your vehicle is towing a trailer or during emergency towing ■
Preventing LKA system malfunctions and operations perf ormed by mistake●
Do not modify the headlights or place stickers, etc., on the surface of the lights.●
Do not modify the suspension etc. If the suspension etc. needs to be replaced, con-
tact your Lexus dealer. ●
Do not install or place anything on the hood or grille. Also, do not install a grille guard
(bull bars, kangaroo bar, etc.). ●
If your windshield needs repair s, contact your Lexus dealer.

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Conditions in which functions may not operate properly
In the following situations, the camera sensor may not detect white (yellow) lines and var-
ious functions may not operate normally. ●
There are shadows on the road that run parallel with, or cover, the white (yellow) lines. ●
The vehicle is driven in an ar ea without white (yellow) lines, such as in front of a tollgate
or checkpoint, or at an intersection, etc.●
The white (yellow) lines are cracked, “Botts ’ dots”, “Raised pavement marker” or stones
are present. ●
The white (yellow) lines cannot be seen or are difficult to see due to sand, etc. ●
The vehicle is driven on a road surface that is wet due to rain, puddles, etc. ●
The traffic lines are yellow (which may be more difficult to recognize than lines that are
white). ●
The white (yellow) lines cross over a curb, etc. ●
The vehicle is driven on a bright surface, such as concrete. ●
The vehicle is driven on a surface that is bright due to reflected light, etc. ●
The vehicle is driven in an area where the brightness changes suddenly, such as at the
entrances and exits of tunnels, etc.●
Light from the headlights of an oncoming vehicle, the sun, etc., enters the camera.●
The vehicle is driven where the road diverges, merges, etc. ●
The vehicle is driven on a slope. ●
The vehicle is driven on a road which t ilts left or right, or a winding road.●
The vehicle is driven on an unpaved or rough road. ●
The vehicle is driven around a sharp curve. ●
The traffic lane is excessively narrow or wide. ●
The vehicle is extremely tilted due to carry ing heavy luggage or having improper tire
pressure. ●
The distance to the preceding vehicle is extremely short. ●
The vehicle is moving up and down a large am ount due to road conditions during driv-
ing (poor roads or road seams). ●
The headlight lenses are dirty and emit a faint amount of light at night, or the beam axis
has deviated. ●
The vehicle is struck by a crosswind. ●
The vehicle has just changed lane s or crossed an intersection.●
Snow tires, etc., are equipped. ■
If the LKA indicator is illuminated in ambe r and a warning message is displayed on the
multi-information display
→ P. 660 ■
Customization
Some functions can be customized. ( → P. 108)

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Driving
RX450h_RX450hL _U_OM48F85UThis mode employs a radar sensor to detect the presence of vehicles up to
approximately 328 ft. (100 m) ahead, de termines the current vehicle-to-vehicle
following distance, and operates to main tain a suitable following distance from
the vehicle ahead. Note that vehicle-to-vehicle distance will cl ose in when traveling on downhill slopes.
Example of constant speed cruising
When there are no vehicles ahead The vehicle travels at the speed set by the driver. The desired vehicle-to-vehicle dis-
tance can also be set by operating the vehicle-to-vehicle distance switch.
Example of deceleration cruising and follow-up cruising
When a preceding vehicle driving sl ower than the set speed appearsWhen a vehicle is detected running ahead of you, the system automatically deceler-
ates your vehicle. When a greater reduction in vehicle speed is necessary, the system
applies the brakes (the stop lights will come on at this time). Th e system will respond to
changes in the speed of the vehicle ahead in order to maintain the vehicle-to-vehicle
distance set by the driver. Approach warning warns you when the system cannot
decelerate sufficie ntly to prevent your vehicle from closing in on the vehicle ahead.
When the vehicle ahead of you stops, your vehicle will also stop (vehicle is stopped by
system control). After the vehicle ahead starts off, pushing the cruise control lever up
or depressing the accelerator pedal will resume follow-up cruising.
Example of acceleration
When there are no longer any preceding vehicles driving slower than the set
speed The system accelerates until the set speed is reached. The system then returns to con-
stant speed cruising.Driving in vehicle-to-vehicle distance control mode
1
2
3

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Driving
RX450h_RX450hL _U_OM48F85UPress “ < ” 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 mirro r 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 CanadaTurning the BSM function/RCTA function on/off 1
2
3

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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 surro unding 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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Turning off both TRAC VSC and Trailer Sway Control systems
To turn the TRAC VSC and Trailer Sway Co ntrol systems off, press and hold for
more than 3 seconds whil e the vehicle is stopped.
The VSC OFF indicator light will come on an d the “Traction Control Turned Off” will be
shown on the multi-information display.
*Press again to turn the systems back on.
* : On vehicles with PCS (Pre-Collision Sy stem), pre-collision brake assist and pre-
collision braking will also be disabled. The PCS warning light will come on and a
message will be displa yed on the multi-info rmation display. ( → P. 296) ■
When the message is displayed on the mu lti-information displa y showing that TRAC
has been disabled even if has not been pressed
TRAC cannot be operated. Contact your Lexus dealer.■
Operating conditions of hill-start assist control
When the following four conditions are met, the hill-start assist control will operate:●
The shift lever is in a position other than P or N (when starting off forward/backward on
an upward incline). ●
The vehicle is stopped ●
The accelerator pedal is not depressed ●
The parking brake is not engaged ■
Automatic system cancelation of hill-start assist control
The hill-start assist control will turn off in any of the following situations: ●
The shift lever is shifted to P or N ●
The accelerator pedal is depressed ●
The parking brake is engaged ●
2 seconds at maximum elapsed after the brake pedal is released ■
Sounds and vibrations caused by the ABS, brake assist, VSC, Trailer Sway Control,
TRAC and hill-start assist control systems ●
A sound may be heard from the engine compartment when the brake pedal is
depressed repeatedly, when the hybrid system is started or just after the vehicle begins
to move. This sound does not indicate that a malfunction has occurred in any of these
systems. ●
Any of the following conditions may occur when the above systems are operating.
None of these indicates that a malfunction has occurred.
• Vibrations may be felt through the vehicle body and steering.
• A motor sound may be heard also after the vehicle comes to a stop.

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Hill-start assist control does not operate effectively when ●
Do not overly rely on hill-start assist control. Hill-start assist control may not operate
effectively on steep inclines and roads covered with ice. ●
Unlike the parking brake, hill-start assist co ntrol is not intended to hold the vehicle
stationary for an exte nded period of time. Do not atte mpt to use hill-start assist con-
trol to hold the vehicle on an incline, as doing so may lead to an accident. ■
When the TRAC/VSC/Trailer Sw ay Control is activated
The slip indicator light flashes. Always drive carefully. Reckle ss driving may cause an
accident. Exercise particular care when the indicator light flashes.■
When the TRAC/VSC/Trailer Sway Control systems are turned off
Be especially careful and drive at a speed appropriate to the road conditions. As these
are the systems to help ensure vehicle stab ility and driving force, do not turn the
TRAC/VSC/Trailer Sway Contro l systems off unless necessary.
Trailer Sway Control is part of the VSC syst em and will not operate if VSC is turned off
or experiences a malfunction. ■
Replacing tires
Make sure that all tires are of the specified size, brand, tread pattern and total load
capacity. In addition, make sure that the tire s are inflated to the recommended tire infla-
tion pressure level.
The ABS, TRAC, Trailer Sway Control and VS C systems will not function correctly if
different tires are installed on the vehicle.
Contact your Lexus dealer for further in formation when replacing tires or wheels.■
Handling of tires and the suspension
Using tires with any kind of problem or modi fying the suspension w ill affect the driving
assist systems, and may cause a system to malfunction. ■
Trailer Sway Control precaution
The Trailer Sway Control system is not able to reduce trailer sway in all situations.
Depending on many factors such as the condit ions of the vehicle, trailer, road surface,
and driving environment, the Trailer Sway Control system may not be effective. Refer to
your trailer owner’s manual for information on how to tow your trailer properly. ■
If trailer sway occurs
Observe the following precautions.
Failing to do so may cause death or serious injury. ●
Firmly grip the steering wh eel. Steer straight ahead.
Do not try to control trailer sway by turning the steering wheel.●
Begin releasing the accelerator pedal immediately but very gradually to reduce
speed.
Do not increase speed. Do not apply vehicle brakes.
If you make no extreme correction with the steering or brakes, your vehicle and trailer
should stabilize. ( → P. 234)