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651-1. For safe use
GS450h_OM_OM30G62U_(U)
1
For safety and security
Exhaust gas precautions
Harmful substance to the human body is included in exhaust gases if inhaled.
WARNING
Exhaust gases include harmful carbon monoxide (CO), which is colorless and odorless.
Observe the following precautions.
Failure to do so may cause exhaust gases enter the vehicle and may lead to an accident
caused by light-headedness, or may lead to death or a serious health hazard.
■Important points while driving
●Keep the trunk lid closed.
●If you smell exhaust gases in the vehicle even when the trunk lid is closed, open the
windows and have the vehicle inspected at your Lexus dealer as soon as possible.
■When parking
●If the vehicle is in a poorly ventilated area or a closed area, such as a garage, stop the
hybrid system.
●Do not leave the vehicle with the hybrid system on for a long time.
If such a situation cannot be avoided, park the vehicle in an open space and ensure
that exhaust fumes do not enter the vehicle interior.
●Do not leave the hybrid system operating in an area with snow build-up, or where it is
snowing. If snowbanks build up around the vehicle while the hybrid system is operat-
ing, exhaust gases may collect and enter the vehicle.
■Exhaust pipe
The exhaust system needs to be checked periodically. If there is a hole or crack caused
by corrosion, damage to a joint or abnormal exhaust noise, be sure to have the vehicle
inspected and repaired by your Lexus dealer.
Page 66 of 548

661-2. Hybrid system
GS450h_OM_OM30G62U_(U)
Hybrid system features
The illustration is an example for explanation and may differ from the actual item.
Gasoline engine
Electric motor (traction motor)
◆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 engine 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 warming up, etc., the gasoline engi ne will not automatically stop. (→P. 68)
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.
1
2
Page 67 of 548

671-2. Hybrid system
GS450h_OM_OM30G62U_(U)
1
For safety and security
◆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 driving with the gasoline engine stopped, a sound, which changes in
accordance with the driving speed, will be played in order to warn people nearby
of the vehicle’s approach. The sound w ill stop when the vehicle speed exceeds
approximately 15 mph (25 km/h).
■Regenerative braking
In the following situations, ki netic 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
Vehicle proximity notification system
The EV indicator comes on when the vehicle is
driven using only the electric motor (traction
motor) or the gasoline engine is stopped.
Page 68 of 548

681-2. Hybrid system
GS450h_OM_OM30G62U_(U)
■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. 459
■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.
■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 sa fety, apply the parking brake and make sure
to shift the shift lever to P 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 trunk lid 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 the air intake vents on the both sides of the rear
seatback.
Page 69 of 548
691-2. Hybrid system
GS450h_OM_OM30G62U_(U)
1
For safety and security
■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
Settings (e.g. on/off operation of the EV indicator) can be changed.
(Customizable features: →P. 494)
Page 70 of 548
701-2. Hybrid system
GS450h_OM_OM30G62U_(U)
Hybrid system precautions
The illustration is an example for explanation and may differ from the actual item.
There are air intake vents on the both
sides of the rear seatback for the pur-
pose of cooling the hybrid battery
(traction battery). When the air intake
vents are blocked, battery operations
will be restricted, leading to poor fuel
economy.
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
Power control unit
Electric motor (traction motor)
Hybrid battery (traction battery) Service plug
High voltage cables (orange)
Air conditioning compressor
Hybrid battery (traction battery) air intake vents
1
2
3
4
5
6
7
Page 71 of 548

711-2. Hybrid system
GS450h_OM_OM30G62U_(U)
1
For safety and security
When a certain level of impact is detected 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. 410)
■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. 406,
410) go off. If there is only a small amount of fuel, the hybrid system may not be able to
start. (The standard amount of fuel is about 2.6 gal. [10.0 L, 2.2 Imp.gal.] [except F
SPORT models] or 2.6 gal. [9.9 L, 2.2 Imp. gal.] [F SPORT models], when the vehicle is
on a level surface. This valu e 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.
Emergency shut off system
Hybrid warning message
Page 72 of 548

721-2. Hybrid system
GS450h_OM_OM30G62U_(U)
WARNING
■High voltage precautions
This vehicle has high voltage DC and AC systems 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.
■Road accident cautions
Observe the following precautions to reduce the risk of death or serious injury:
●Pull your vehicle off the road, apply the park ing brake, shift the shift lever to P, and
turn the hybrid system off.
●Do not touch the high voltage parts, cables and connectors.
●If electric wires are exposed inside or ou tside your vehicle, an electric shock may
occur. Never touch exposed electric wires.
●If a fluid leak occurs, do not touch the flui d as it may be strong alkaline electrolyte
from the hybrid battery (traction battery). If it comes into contact with your skin or
eyes, wash it off immediately with a large amount of water or, if possible, boric acid
solution. Seek immedi ate medical attention.
●If a fire occurs in the hybrid vehicle, leave the vehicle as soon as possible. Never use a
fire extinguisher that is not meant for el ectric fires. Using even a small amount of
water may be dangerous.
●If your vehicle needs to be towed, do so with rear wheels raised. If the wheels con-
nected to the electric motor (traction motor) are on the ground when towing, the
motor may continue to generate elec tricity. This may cause a fire. (→P. 398)
●Carefully inspect the ground under the vehicl e. If you find that liquid has leaked onto
the ground, the fuel system may have been damaged. Leave the vehicle as soon as
possible.
●Never try to open the service plug access
hole located behind the rear seats. The ser-
vice plug is used only when the vehicle is ser-
viced and is subject to high voltage.