2018 LEXUS RX450h heating

82 1-3. Hybrid system
RX450h_RX450hL _U_OM48F85UNOTICE ■
Hybrid battery (traction battery) air intake/discharge vents ●
Do not place objects that will block the air intake vents. The hybr id battery (traction
battery) may overheat and be damaged. ●
Clean the air intake/discharge vents regularl y to prevent the hybrid battery (traction
battery) from overheating.●
Do not get water or foreign materials in either the air intake/discharge vents as this
may cause a short circuit and damage the hybrid battery (traction battery). ●
Do not carry large amounts of water such as water cooler bottles in the vehicle. If
water spills onto the hybrid battery (tract ion battery), the battery may be damaged.
Have the vehicle inspected by your Lexus dealer.

100 2. Instrument cluster
RX450h_RX450hL _U_OM48F85U■
Tachometer
Hybrid System Indicator switches to the tachometer when driving mode is in sport mode.
The settings of the tachometer display can be changed on of the multi-information
display. ( → P. 108)■
Engine speed
On hybrid vehicles, engine speed is precisel y controlled in order to help improve fuel
efficiency and reduce exhaust emissions etc.
There are times when the engine speed that is displayed may differ even when vehicle
operation and driving conditions are the same. ■
Brightness of the meters (d ay mode and night mode)
The brightness of the meters is changed between day mode and night mode. ●
Day mode: When the tail lights are off or when the tail lights are on but the surrounding
area is bright ●
Night mode: When the tail lights are on and the surrounding area is dark ■
Outside temperature display ●
In the following situations, the correct outside temperature may not be displayed, or the
display may take longer than normal to change:
• When stopped, or driving at low speeds (less than 12 mph [20 km/h])
• When the outside temperature has changed suddenly (at the entrance/exit of a
garage, tunnel, etc.) ●
When “ − − ” or “E” is displayed, the sy stem may be malfunctioning.
Take your vehicle to your Lexus dealer. ■
Clock settings screen (vehicles with a navigation system only)
If the clock adjustment screen is displayed continuously wh en attempting to change the
clock settings, the system may be malfunctioning.
Have the vehicle inspected by your Lexus dealer. ■
Customization
Some functions can be customized. ( → P. 108)
NOTICE ■
To prevent damage to the engine and its components●
Do not let the indicator needle of the tachometer enter the red zone, which indicates
the maximum engine speed. ●
The engine may be overheating if the engine coolant temperature gauge is in the red
zone (H). In this case, immediately stop the vehicle in a safe place, and check the
engine after it has cooled completely. ( → P. 702)

218 4-1. Before driving
RX450h_RX450hL _U_OM48F85UWARNING
Observe the following precautions.
Failure to do so may result in death or serious injury. ■
When taking a nap in the vehicle
Always turn the hybrid system off. Otherwise, if you accidentally move the shift lever or
depress the accelerator pedal, this could cause an accident or fire due to hybrid system
overheating. Additionally, if the vehicle is parked in a poorly ve ntilated area, exhaust
gases may collect and enter the vehicle, lead ing to death or a serious health hazard.■
When braking ●
When the brakes are wet, drive more cautiously.
Braking distance increases when the brakes are wet, and this may cause one side of
the vehicle to brake differently than the other side. Also, the parking brake may not
securely hold the vehicle. ●
If the electronically controlled brake function does not operate, do not follow other
vehicles closely and avoid hills or sharp turns that require braking.
In this case, braking is still possible, bu t the brake pedal should be depressed more
firmly than usual. Also, the braking distan ce will increase. Have your brakes fixed
immediately. ●
The brake system consists of 2 or more indi vidual hydraulic systems; if one of the sys-
tems fails, the other(s) will still operate. In this case, the brake pedal should be
depressed more firmly than usual and the braking distance will increase. Have your
brakes fixed immediately. ■
If the vehicle becomes stuck
Do not spin the wheels excessive ly when any of the tires is up in the air, or the vehicle is
stuck in sand, mud, etc. This may damage the driveline components or propel the vehi-
cle forward or backward, causing an accident.

232 4-1. Before driving
RX450h_RX450hL _U_OM48F85U●
To maintain engine braking efficien cy and charging system performance
when using engine braking, do no t put the transmission in D. ( → P. 246)●
Instability happens more fr equently when descending steep or long downhill
grades. Before descending, slow down and downshift. Do not make sudden
downshifts while descending st eep or long downhill grades.●
Avoid holding the brake pedal down too long or applying the brakes too fre-
quently. This could cause the brakes to overheat and result in reduced braking
efficiency. ●
Due to the added load of the trailer, yo ur vehicle’s engine may overheat on hot
days (at temperatures over 85 ° F [30 ° C]) when driving up a long or steep
grade. If the engine coolant temperat ure gauge indicates overheating, imme-
diately turn off the air conditioning (if in use), pull your vehicle off the road and
stop in a safe spot. ( → P. 702)●
Always place wheel blocks under both the vehicle’s and the trailer’s wheels
when parking. Put the transmission in P and apply the parking brake. Avoid
parking on a slope, but if unavoidable, do so only after performing the follow-
ing:
Apply the brakes and keep them applied.
Have someone place wheel blocks under both the vehicle’s and trailer’s
wheels.
When the wheel blocks are in place, release the brakes slowly until the
blocks absorb the load.
Shift into P and apply the parking brake.
Turn off the hybrid system.●
When restarting afte r parking on a slope:
With the transmission in P, start the hybrid system. Be sure to keep the
brake pedal depressed.
Shift into a forward gear. If reversing, shift into R.
If the parking brake is in manual mode, release the parking brake.
( → P. 254)
Release the brake pedal, and slowly pull or back away from the wheel
blocks. Stop and apply the brakes.
Have someone retrieve the blocks. 1
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242 4-2. Driving procedures
RX450h_RX450hL _U_OM48F85U■
Steering lock
After turning the power switch off and openin g and closing the doors, the steering wheel
will be locked due to the steering lock func tion. Operating the power switch again auto-
matically cancels the steering lock. ■
When the steering lock cannot be released
■
Steering lock motor overheating prevention
To prevent the steering lock motor from overheating, operation of the motor may be sus-
pended if the hybrid system is turned on an d off repeatedly in a short period of time. In
this case, refrain from operating the hybrid system. Afte r about 10 seconds, the steering
lock motor will resume functioning. ■
When “Access System with Elec. Key Malf unction See Owner’s Manual” is displayed
on the multi-information display
The system may be malfunctio ning. Have the vehicle inspected by your Lexus dealer
immediately. ■
If the “READY” indicator does not come on
In the event that the “READY” indicator does not come on even after performing the
proper procedures for starting the vehicl e, contact your Lexus dealer immediately.■
If the hybrid system is malfunctioning
→ P. 79 ■
If the electronic key battery is depleted
→ P. 630 ■
Operation of the power switch ●
If the switch is not pressed shortly and firm ly, the power switch mode may not change or
the hybrid system may not start. ●
If attempting to restart the hybrid system immediately after turning the power switch off,
the hybrid system may not start in some cases. After turning the power switch off,
please wait a few seco nds before restarting the hybrid system.■
If the smart access system wi th push-button start has been deactivated by a customized
setting
→ P. 692“Steering Wheel Lock Pr ess Power Switch while
Turning Wheel” will be displayed on the multi-
information display.
Check that the shift lever is in P. Press the power
switch shortly and firmly while turning the steer-
ing wheel left and right.

254 4-2. Driving procedures
RX450h_RX450hL _U_OM48F85UThe parking brake can be set and released manually.
Sets the parking brake The parking brake indicator light and
parking brake light will turn on.
Pull and hold the parking brake switch if
an emergency occurs and it is necessary
to operate the parking brake while driv-
ing.
Releases the parking brake Operate the parking brake switch while
depressing the brake pedal. Make sure
that the parking brake indicator light
and parking brake light turn off.
If the parking brake indicator light and
parking brake lamp flashes, operate the
switch again. ( → P. 660)■
Parking the vehicle
→ P. 212 ■
Parking brake operation ●
When the power switch is not in ON mode, the parking brake cannot be released using
the parking brake switch. ●
When the power switch is not in ON mode , automatic mode (automatic brake setting
and releasing) is not available. ■
If “Parking Brake Overheated Parking Brak e Unavailable” is displayed on the multi-
information display
If the parking brake is operated repeatedly over a short period of time, the system may
restrict operation to prevent overheating. If this happens, refrain from operating the
parking brake. Normal operation wi ll return after about 1 minute.■
If “EPB Activation Stopped Incompletely” or “Parking Brake Unavailable” is displayed
on the multi-information display
Operate the parking brake switch. If the message does not disappear after operating the
switch several times, the system may be ma lfunctioning. Have th e vehicle inspected by
your Lexus dealer immediately. ■
Parking brake operation sound
When the parking brake operates, a motor so und (whirring sound) may be heard. This
does not indicate a malfunction.Manual mode U.S.A. Canada
Parking
brake light1
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3794-5. Using the driving support systems
4
Driving
RX450h_RX450hL _U_OM48F85U 
Vehicles without Adaptive Variable Suspension System
Normal mode
Provides an optimal balance of fuel ec onomy, quietness, and dynamic perfor-
mance. Suitable for city driving. Press the switch to change the driving mode to normal mode when Eco drive mode or
sport mode is selected.
Eco drive mode
Helps the driver accelerate in an eco-fr iendly manner and improve fuel econ-
omy through moderate throttle charact eristics and by controlling the opera-
tion of the air conditioning system (heating/cooling). When not in Eco drive mode, if the driving mode select switch is tu rned to the left, the
Eco drive mode indicator will come on.
Sport mode
Controls the hybrid system to prov ide quick, powerful acceleration. This
mode also changes the steering feel, maki ng it suitable for when agile driving
response is desired, such as when driving on roads with many curves. When not in sport mode, if the driving mode select switch is turned to the right, the
“SPORT” indicator will comes on.Driving mode select switch The driving modes can be selected to suit driving conditions.
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3814-5. Using the driving support systems
4
Driving
RX450h_RX450hL _U_OM48F85UEco drive mode
Helps the driver accelerate in an eco-fr iendly manner and improve fuel econ-
omy through moderate throttle charact eristics and by controlling the opera-
tion of the air conditioning system (heating/cooling). When not in Eco drive mode, if the driving mode select switch is tu rned to the left, the
Eco drive mode indicator will come on.
Sport mode
•SPORT S mode
Controls the hybrid system to prov ide quick, powerful acceleration. This
mode is suitable for when agile drivin g response is desired, such as when
driving on roads with many curves. When not in SPORT S mode, if the driving mode select switch is turned to the
right, the “SPORT S” indicator will come on.
•SPORT S+ mode
Helps to ensure steering performanc e and driving stability by simultane-
ously controlling the steering and suspension in addition to the hybrid sys-
tem. Suitable for sportier driving. When in SPORT S mode, if the driving mode select switch is turned to the right,
the “SPORT S+” indicator will come on.■
Operation of the air conditioning system in Eco drive mode
Eco drive mode controls the heating/cooling operations and fan speed of the air condi-
tioning system to enhance fuel efficiency. To improve air conditioning performance,
adjust the fan speed or turn off Eco drive mode. ■
Automatic deactivation of sport mode and customized mode
If the power switch is turned off after driv ing in sport mode or customized mode, the
drive mode will be changed to normal mode. ■
Driving mode pop-up display (12.3-inch display only)
When the driving mode is changed, the sele cted driving mode will be temporarily dis-
played on the side display. ( → P. 504)Function Setting
Powertrain Normal
Power
Eco
Chassis Normal
Sport
Air conditioning system Normal
Eco2
3