2018 LEXUS RX450h brakes

234 4-1. Before driving
RX450h_RX450hL _U_OM48F85U■
Break-in schedule
If your vehicle is new or equipped with any new power train components (such as an
engine, hybrid transmission, rear differenti al or wheel bearing), Lexus recommends that
you do not tow a trailer until the vehicle ha s been driven for over 500 miles (800 km).
After the vehicle has been driven for over 500 miles (800 km), you can start towing.
However, for the next 500 miles (800 km), drive the vehicle at a speed of less than
50 mph (80 km/h) when towing a trailer, and avoid full throttle acceleration.■
Maintenance ●
If you tow a trailer, your vehicle will requir e more frequent maintenance due to the addi-
tional load. (See “Warranty and Services Guide”, “Owner’s Manual Supplement” or
“Scheduled Maintenance”.) ●
Retighten the fixing bolts of the towing ba ll and bracket after approximately 600 miles
(1000 km) of trailer towing. ■
If trailer sway occurs
One or more factors (crosswinds, passing ve hicles, rough roads, etc.) can adversely
affect handling of your vehicle and trailer, causing instability. ●
If trailer swaying occurs:
• Firmly grip the steering wh eel. Steer straight ahead.
Do not try to control trailer sway ing by turning the steering wheel.
• Begin releasing the accelerator pedal im mediately but very gradually to reduce
speed.
Do not increase speed. Do not apply vehicle brakes.
If you make no extreme correction with the st eering or brakes, your vehicle and trailer
should stabilize. (if enabled, Trailer Sway Control can also he lp to stabilize the vehicle and
trailer.) ●
After the trailer sw aying has stopped:
• Stop in a safe place. Get all occupants out of the vehicle.
• Check the tires of the vehicle and the trailer.
• Check the load in the trailer.
Make sure the load has not shifted.
Make sure the tongue weight is appropriate, if possible.
• Check the load in the vehicle.
Make sure the vehicle is not ov erloaded after occupants get in.
If you cannot find any problems, the speed at which trailer swaying occurred is beyond
the limit of your particular vehicle-trailer combination.
Drive at a lower speed to prevent instability. Remember that swaying of the towing vehi-
cle-trailer increases as speed increases.

2354-1. Before driving
4
Driving
RX450h_RX450hL _U_OM48F85UWARNING ■
Trailer towing precautions
To tow a trailer safely, use extreme care and drive the vehicle in accordance with the
trailer’s characteristics and operating conditio ns. Failure to do so could cause an acci-
dent resulting in deat h or serious injury. Vehicle stab ility and braking performance are
affected by trailer stability, brake setting an d performance, and the hitch. Your vehicle
will handle differently when towing a trailer. ■
To avoid accident or injury ●
Do not exceed the TWR, unbraked TWR, GCWR, GVWR or GAWR. ●
If the gross trailer weight is over 2000 lb. (907 kg), a sway control device with suffi-
cient capacity is required. ●
Adjust the tongue weight within the approp riate range. Place heavier loads as close
to the trailer axle as possible. ●
Do not exceed 65 mph (104 km/h), the posted towing speed limit or the speed limit
for your trailer as set forth in your trai ler owner’s manual, whichever is lowest. Slow
down sufficiently before making a turn, in cr oss winds, on wet or slippery surface, etc.
to help avoid an accident. If you experien ce a vehicle-trailer in stability from reducing
a certain speed, slow down and make sure you keep your vehicle speed under the
speed of which you expe rience the instability.●
Do not make jerky, abrupt or sharp turns. ●
Do not apply the brakes suddenly as you ma y skid, resulting in jackknifing and loss of
vehicle control. This is especially true on wet or slippery surfaces.●
Do not exceed the trailer hitch assembly weight, gross vehicle weight, gross axle
weight and trailer tongue weight capacities. ●
Do not use the following systems when trailer towing.
• Dynamic radar cruise cont rol with full-speed range
• LKA (Lane-Keeping Assist)
• PCS (Pre-Collision system)
• BSM (Blind Spot Monitor)
*
* : If equipped ●
Slow down and downshift before descending steep or long downhill grades. Do not
make sudden downshifts while descending steep or long downhill grades. ●
Vehicle-trailer instability is more likely on steep long downhills. Before descending
steep or long downhill grades, slow down and downshift. Do not make sudden down-
shifts when descending steep or long do wnhill grades. Avoid ho lding the brake pedal
down too long or applying the brakes too frequently. This could cause the brakes to
overheat and result in reduced braking efficiency. ●
Do not tow a trailer when the compact sp are tire is installed on your vehicle.

236 4-1. Before driving
RX450h_RX450hL _U_OM48F85UWARNING ■
Hitch
Trailer hitch assemblies have different weight capacities established by the hitch manu-
facturer. Even though the vehicle may be phys ically capable of towing a higher weight,
the operator must determine the maximum weight rating of the particular hitch assem-
bly and never exceed the maximum weight rating specified for the trailer-hitch.
Exceeding the maximum weight rating set by the trailer-hitch manufacturer can cause
an accident resulting in death or serious personal injuries. ■
When towing a trailer
Lexus recommends trailers with brakes that conform to any applicable federal and
state/provincial regulations. ●
If the gross trailer weight exceeds unbraked TWR, trailer brakes are required. Lexus
recommends trailers with brakes that conform to all applicable federal and state/pro-
vincial regulations. ●
Never tap into your vehicle’s hydraulic system, as this will lower the vehicle’s braking
effectiveness. ●
Never tow a trailer without using a safety chain securely attached to both the trailer
and the vehicle. If damage occurs to the co upling unit or hitch ball, there is danger of
the trailer wandering into another lane.
NOTICE ■
When installing a trailer hitch
Use only the position recommended by your Lexus dealer. Do not install the trailer
hitch on the bumper; this may cause body damage. ■
Do not directly splice trailer lights
Do not directly splic e trailer lights. Directly splicin g trailer lights may damage your
vehicle’s electrical system and cause a malfunction.

256 4-2. Driving procedures
RX450h_RX450hL _U_OM48F85UTurns the brake hold system on The brake hold standby indicator
(green) comes on. Wh ile the system is
holding the brakes, the brake hold oper-
ated indicator (yellow) will illuminate. ■
Brake hold system operating conditions
The brake hold system cannot be turn ed on in the following conditions:●
The driver’s door is not closed. ●
The driver’s seat seat belt is not buckled.
If either of the conditions above are detected when the brake hold system is enabled, the
system will turn off and the brake hold standby in dicator light will go off. In addition, if any
of the conditions are detected while the sy stem is holding the brakes, a warning buzzer
will sound and a message will be shown on th e multi-information di splay. The parking
brake will then be set automatically. ■
Brake hold function ●
If the brake pedal is left released for a pe riod of about 3 minutes after the system has
started holding the brakes, the parking brake will be set automatically. In this case, a
warning buzzer sounds and a message is shown on the multi- informatio n display.●
To turn the system off while the system is holding the brakes, firmly depress the brake
pedal and press the switch again. ●
The brake hold function may not hold the vehicle when the vehicle is on a steep incline.
In this situation, it may be necessary for the driver to apply the brakes. A warning
buzzer will sound and the mult i-information display will info rm the driver of this situa-
tion. If a warning message is shown on the multi-information display, read the message
and follow the instructions.Brake Hold The brake hold system keeps the brake appl ied when the shift lever is in D, S or
N with the system on and the brake peda l has been depressed to stop the vehi-
cle. The system releases the brake wh en the accelerator pedal is depressed
with the shift lever in D or S to allow smooth start off.

2574-2. Driving procedures
4
Driving
RX450h_RX450hL _U_OM48F85U■
When the parking brake is set automatically while the system is holding the brakes
Perform any of the following operat ions to release the parking brake.●
Depress the accelerator pedal. (The parking brake will not be released automatically if
the seat belt is not fastened.) ●
Operate the parking brake switch with the brake pedal depressed.
Make sure that the parking brake indicator light goes off. ( → P. 253) ■
When an inspection at your Lexus dealer is necessary
When the brake hold standby indicator (green) does not illu minate even when the brake
hold switch is pressed with the brake hold system operating conditions met, the system
may be malfunctioning. Ha ve the vehicle inspected at your Lexus dealer. ■
If “Brake Hold Fault Depress Brake to Deacti vate Visit Your Dealer” is displayed on the
multi-information display
The system may be malfunctioning. Have th e vehicle inspected by your Lexus dealer.■
Warning messages and buzzers
Warning messages and buzzers are used to indicate a system malfunction or to inform
the driver of the need for caution. If a warn ing message is shown on the multi-information
display, read the message and follow the instructions.■
If the brake hold operated indicator flashes
→ P. 660
WARNING ■
When the vehicle is on a steep incline
When using the brake hold system on a steep incline exercise caution. The brake hold
function may not hold the vehicle in such a situation. ■
When stopped on a slippery road
The system cannot stop the vehicle when the gripping ability of the tires has been
exceeded. Do not use the system when stopped on a slippery road.
NOTICE ■
When parking the vehicle
The brake hold system is not designed for use when parking the vehicle for a long
period of time. Turning the power switch off while the system is holding the brakes may
release the brakes, which would cause the vehicle to move. When operating the power
switch, depress the brake pedal, shift the shift lever to P and set the parking brake.

286 4-5. Using the driving support systems
RX450h_RX450hL _U_OM48F85UPCS (Pre-Collision System) The pre-collision system uses a radar sensor and camera sensor to detect
vehicles and pedestrians
in front of your vehicle. When the system determines
that the possibility of a frontal collision with a vehicle or pedestrian is high, a
warning operates to urge the driver to take evasive action and the potential
brake pressure is increased to help the driver avoid the collision. If the system
determines that the possibility of a fr ontal collision with a vehicle or pedes-
trian is extremely high, the brakes are automatically applied to help avoid the
collision or help reduce the impact of the collision.
The pre-collision system can be disabled/enabled and the warning timing can
be changed. ( → P. 290)

2954-5. Using the driving support systems
4
Driving
RX450h_RX450hL _U_OM48F85U• After the hybrid system has started the vehicle has not been driven for a certain
amount of time
• While making a left/right turn and for a few seconds after making a left/right turn
• While driving on a curve and for a few seconds after driving on a curve
• If your vehicle is skidding
• If the wheels are misaligned
• If a wiper blade is blocking the camera sensor
• The vehicle is wobbling.
• The vehicle is being driven at extremely high speeds.
• When driving on a hill
• If the radar sensor or ca mera sensor is misaligned●
In some situations such as the following, sufficient braking forc e may not be obtained,
preventing the system from performing properly:
• If the braking functions cannot operate to their full extent, such as when the brake
parts are extremely cold, extremely hot, or wet
• If the vehicle is not properly maintained (brakes or tires are excessively worn,
improper tire inflation pressure, etc.)
• When the vehicle is being driven on a gravel road or other slippery surface●
Some pedestrians such as the following may not be detected by the radar sensor and
camera sensor, preventing the system from operating properly:
• Pedestrians shorter than approximately 3.2 ft. (1 m) or taller than approximately 6.5
ft. (2 m)
• Pedestrians wearing oversized clothing (a ra in coat, long skirt, etc.), making their sil-
houette obscure
• Pedestrians who are carrying large baggage, holding an umbrella, etc., hiding part
of their body
• Pedestrians who are bending forward or squatting
• Pedestrians who are pushing a stroller , wheelchair, bicycle or other vehicle
• Groups of pedestrians which are close together
• Pedestrians who are wearing white and look extremely bright
• Pedestrians in the dark, such as at night or while in a tunnel
• Pedestrians whose clothing appears to be nearly the same color or brightness as
their surroundings
• Pedestrians near walls, fences , guardrails, or large objects
• Pedestrians who are on a metal object (manhole cover, steel plate, etc.) on the road
• Pedestrians who are walking fast
• Pedestrians who are changing speed abruptly
• Pedestrians running out from be hind a vehicle or a large object
• Pedestrians who are extremely close to the side of the vehicle (outside rear view
mirror, etc.)• If the front of the vehicle is raised or low-
ered

3094-5. Using the driving support systems
4
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
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