2019 LEXUS RX450H Owners Manual

731-2. Child safety
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For safety and security
RX450h_RX450hL_U
WARNING
■When installing a child restraint system
Observe the following precautions.
Failure to do so may result in death or serious injury.
●Firmly attach the top tether strap and make sure that the belt is not twisted.
●Do not attach the top strap to anything other than the anchor bracket of the seat the
child restraint system is installed to.
●Follow all installation instructions provided by the child restraint system manufacturer.
●When installing the child restraint system with the head restraint being raised, after
the head restraint has been raised and then the anchor bracket has been fixed, do not
lower the head restraint.
●When installing a child restraint system in th e rear center seat, adjust both seat cush-
ions to the same position an d align both seatbacks at the same angle. The seatbacks
must be adjusted to the same angle. Othe rwise, the child restraint system cannot be
securely restrained and this may cause death or serious injuries in the event of sudden
braking, sudden swerving or an accident.
●If the seat is adjusted, reconfirm the security of the child restraint system.
NOTICE
■Anchor brackets (for top tether strap)
When not in use, make certain to close the lid. If it remains open, the lid may be dam-
aged.

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RX450h_RX450hL_U1-3. Hybrid system
The illustration is an example for explan
ation and may differ from the actual item.
Gasoline engine
Front electric motor (traction motor)
Rear electric motor (traction motor)
Hybrid system features
Your vehicle is a hybrid vehicle. It has characteristics different from conven-
tional vehicles. Be sure you are closely familiar with the characteristics of your
vehicle, and operate it with care.
The hybrid system combines the use of a gasoline engine and an electric
motor (traction motor) according to driving conditions, improving fuel effi-
ciency and reducing exhaust emissions.
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751-3. Hybrid system
1
For safety and security
RX450h_RX450hL_U
◆When stopped/during start off
The gasoline engine stops* when the vehicle is stopped. During start off, the
electric motor (traction mo tor) drives the vehicle. At slow speeds or when
traveling down a gentle slope, the engi ne is stopped* and the electric motor
(traction motor) is used.
When the shift lever is in N, the hybrid battery (traction battery) is not being
charged.
*: When the hybrid battery (traction battery) requires charging or the engine is warm- ing up, etc., the gasoline engine will not automatically stop. (P. 76)
◆During normal driving
The gasoline engine is predominantly used. The electric motor (traction
motor) charges the hybrid battery (traction battery) as necessary.
◆When accelerating sharply
When the accelerator pedal is depressed heavily, the power of the hybrid bat-
tery (traction battery) is added to that of the gasoline engine via the electric
motor (traction motor).
◆When braking (regenerative braking)
The wheels operate the electric motor (traction motor) as a power generator,
and the hybrid battery (traction battery) is charged.
When the gasoline engine is off while driving, a sound is produced to warn
pedestrians, people riding bicycles or other people and vehicles in the surround-
ing area that the vehicle is approaching. The pitch of the sound varies according
to the vehicle speed. When the vehicl e speed becomes approximately 15 mph
(25 km/h) or more, the notification sound turns off.
Vehicle proximity notification system

761-3. Hybrid system
RX450h_RX450hL_U
■Regenerative braking
In the following situations, kinetic energy is converted to electric energy and decelera-
tion force can be obtained in conjunction with the recharging of the hybrid battery (trac-
tion battery).
●The accelerator pedal is released while driving with the shift lever in D or S.
●The brake pedal is depressed while driving with the shift lever in D or S.
■EV indicator
■Conditions in which the gasoline engine may not stop
The gasoline engine starts and stops automati cally. However, it may not stop automati-
cally in the following conditions:
●During gasoline engine warm-up
●During hybrid battery (traction battery) charging
●When the temperature of the hybrid battery (traction battery) is high or low
●When the heater is switched on
■Charging the hybrid battery (traction battery)
As the gasoline engine charges the hybrid battery (traction battery), the battery does not
need to be charged from an ou tside source. However, if the vehicle is left parked for a
long time the hybrid battery (traction batter y) will slowly discharge. For this reason, be
sure to drive the vehicle at least once every few months for at least 30 minutes or 10
miles (16 km). If the hybrid battery (traction battery) beco mes fully discharged and you
are unable to start the hybrid system, contact your Lexus dealer.
■Charging the 12-volt battery
 P. 698
■After the 12-volt battery has discharged or when the terminal has been removed and
installed during exchange, etc.
The gasoline engine may not stop even if the vehicle is being driven by the hybrid battery
(traction battery). If this continues fo r a few days, contact your Lexus dealer.
The EV indicator comes on when the vehicle is
driven using only the el
ectric motor (traction
motor) or the gasoline engine is stopped.

771-3. Hybrid system
1
For safety and security
RX450h_RX450hL_U
■Sounds and vibrations specific to a hybrid vehicle
There may be no engine sound or vibration even though the vehicle is able to move with
the “READY” indicator is illuminated. For safety, make sure to shift the shift lever to P and
apply the parking brake when parked.
The following sounds or vibrations may occu r when the hybrid system is operating and
are not a malfunction:
●Motor sounds may be heard from the engine compartment.
●Sounds may be heard from the hybrid battery (traction battery) behind the rear seats
when the hybrid system starts or stops.
●Relay operating sounds such as a snap or so ft clank will be emitted from the hybrid bat-
tery (traction battery), behind the rear se ats, when the hybrid system is started or
stopped.
●Sounds from the hybrid system may be heard when the back door is open.
●Sounds may be heard from the transmission wh en the gasoline engine starts or stops,
when driving at low spee ds, or during idling.
●Engine sounds may be heard when accelerating sharply.
●Sounds may be heard due to regenerative braking when the brake pedal is depressed
or as the accelerator pedal is released.
●Vibration may be felt when the ga soline engine starts or stops.
●Cooling fan sounds may be heard from th e air intake vents under the rear seats.
■Vehicle proximity notification system
In the following cases, the vehicle proximity notification system may be difficult for sur-
rounding people to hear.
●In very noisy areas
●In the wind or the rain
Also, as the vehicle proximity notification system is installed on the front of the vehicle, it
may be more difficult to hear from the re ar of the vehicle compared to the front.
■Maintenance, repair, recycling, and disposal
Contact your Lexus dealer regarding mainte nance, repair, recycling and disposal. Do
not dispose of the vehicle yourself.
■Customization
Some functions can be customized. ( P. 736)

781-3. Hybrid system
RX450h_RX450hL_U
The illustration is an example for explanation and may differ from the actual item.
Hybrid system precautions
Take care when handling the hybrid system, as it is a high voltage system
(about 650 V at maximum) as well as contains parts that become extremely
hot when the hybrid system is operating. Obey the warning labels attached to
the vehicle.
Warning label
Hybrid battery (traction battery)
Rear electric motor (traction motor)
Service plug
High voltage cables (orange) Front electric motor (traction
motor)
Power control unit
Air conditioning compressor1
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791-3. Hybrid system
1
For safety and security
RX450h_RX450hL_U
The air intake/discharge vents for the
hybrid battery (traction battery) are
located under the rear seats and in lug-
gage compartment respectively. If the
air intake vents are blocked, it could
lead to a reduction in hybrid battery
(traction battery) output.
*: RX450h
When a certain level of impact is detect ed by the impact sensor, the emergency
shut off system blocks the high voltage current and stops the fuel pump to mini-
mize the risk of electrocution and fuel leakage. If the emergency shut off system
activates, your vehicle will not restart. To restart the hybrid system, contact your
Lexus dealer.
A message is automatically displayed wh en a malfunction occurs in the hybrid
system or an improper operation is attempted.
If a warning message is shown on the
multi-information display, read the
message and follow the instructions.
( P. 667)
Hybrid battery (traction battery) air intake/discharge vents
Air intake vents
Air discharge vents*
Emergency shut off system
Hybrid warning message

801-3. Hybrid system
RX450h_RX450hL_U
■If a warning light comes on, a warning message is displayed, or the 12-volt battery is dis-
connected
The hybrid system may not start. In this case, try to start the system again. If the “READY”
indicator does not come on, contact your Lexus dealer.
■Running out of fuel
When the vehicle has run out of fuel and the hybrid system cannot be started, refuel the
vehicle with at least enough gasoline to make the low fuel level warning light ( P. 662)
go off. If there is only a small amount of fu el, the hybrid system may not be able to start.
(The standard amount of fuel is about 2.9 gal. [11.0 L, 2.4 Imp.gal.], when the vehicle is on
a level surface. This value may vary when the vehicle is on a slope. Add extra fuel when
the vehicle is inclined.)
■Electromagnetic waves
●High voltage parts and cables on hybrid ve hicles incorporate electromagnetic shield-
ing, and therefore emit approximately the same amount of electromagnetic waves as
conventional gasoline powered vehicles or home electronic appliances.
●Your vehicle may cause sound interference in some third party-produced radio parts.
■Hybrid battery (traction battery)
The hybrid battery (traction battery) has a li mited service life. The lifespan of the hybrid
battery (traction battery) can change in acco rdance with driving style and driving condi-
tions.
WARNING
■High voltage precautions
This vehicle has high voltage DC and AC sy stems as well as a 12-volt system. DC and
AC high voltage is very dangerous and can cause severe burns and electric shock that
may result in death or serious injury.
●Never touch, disassemble, remove or replace the high voltage parts, cables or their
connectors.
●The hybrid system will become hot after starting as the system uses high voltage. Be
careful of both the high voltage and the high temperature, and always obey the warn-
ing labels attached to the vehicle.
●Never try to open the service plug access
hole located under the rear seat. The service
plug is used only when the vehicle is serviced
and is subject to high voltage.