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1-1. Hybrid system
Hybrid system
Your vehicle is a hybrid vehicle. It has characteristics different from con-
ventional vehicles. Be sure you are closely familiar with the characteristics
of your vehicle, and operate with care.
The hybrid system combines a gasoline engine and an electric motor (trac-
tion motor) according to driving conditions, improving fuel efficiency and
reducing exhaust emissions.
Gasoline engine
Electric motor (Traction motor)
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■Regenerative braking
The motor generator converts kinetic energy to electric energy when:
●The accelerator pedal is released.
●The brake pedal is depressed with the shift lever in “D” or “S”.
■When stopped/during take-off
The gasoline engine stops when the vehicle is stopped. During take-
off, the electric motor (traction motor) drives the vehicle. At slow
speeds or when traveling down a gentle slope, the engine is stopped
and the motor is used.
■ During normal driving
The gasoline engine is predominantly used. The electric motor
(traction motor) charges the hybrid battery as necessary.
■ When accelerating sharply
The power of the hybrid battery (traction battery) is added via elec-
tric motor (traction motor) to that of the gasoline engine.
■ When braking (Regenerative brake)
The electric motor (traction motor) charges the hybrid battery
(traction battery).
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■Conditions in which the gasoline engine may not stop
The gasoline engine starts and stops automatically. However, it may not stop auto-
matically in the following conditions:
●During gasoline engine warm-up
●During hybrid battery (traction battery) charging
●During low or high hybrid battery (traction battery) temperature
■Charging the battery
●As the gasoline engine charges the hybrid battery (traction battery), the battery
does not need to be charged from an outside source. However, if the vehicle is
left parked for a long time the hybrid battery will slowly discharge. For this rea-
son, 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 becomes fully discharged and
you are unable to jump-start the vehicle with the 12 volt battery, contact your
Lexus dealer.
●If the shift lever is in “N”, the hybrid battery (traction battery) will not be
charged. When driving in heavy traffic, operate the vehicle with the shift lever in
“D” or “S” to avoid discharging the battery.
■After the 12 volt battery has discharged or has been changed or removed
The gasoline engine may not stop even if the vehicle is running on the hybrid battery
(traction battery). If this continues for a few days, contact your Lexus dealer.
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■Sounds and vibrations specific to a hybrid vehicle
There may be no engine sounds or vibration even though the vehicle is able to
move. Always put the shift lever in “P” when parked.
The following sounds or vibrations may occur 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
seat when the hybrid system starts or stops.
●Sounds from the hybrid system may be heard when the trunk lid is open.
●Sounds may be heard from the transmission when the hybrid system starts or
stops.
●Engine sounds may be heard when accelerating sharply.
●Sounds may be heard from the regenerative brake when you press the brake
pedal.
●Vibration may be felt when the gasoline engine starts or stops.
●You may hear cooling fan sounds coming from the air intake vents behind the
rear seat.
■Maintenance, repair, recycling, and disposal
Contact your Lexus dealer regarding maintenance, repair, recycling and disposal.
Do not dispose of the vehicle yourself.
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High voltage componentsTake care when handling the hybrid system, as it contains a high voltage
system (about 650V at maximu m) as well as parts that become
extremely hot when the hybrid system is operating. Obey the caution
labels attached to the vehicle. Power control unit
Air conditioning compressor
Hybrid battery (Traction bat-
tery)
DC/DC converter
Service plug
Electric motor (Traction motor)
High voltage cables (orange
color)
Caution label
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■Hybrid battery air vent
Hybrid battery air vent
There is an air intake vent on the
package tray for the purpose of
cooling the hybrid battery (trac-
tion battery). If the vent becomes
blocked, the hybrid battery may
overheat, leading to a reduction in
hybrid battery output.
Emergency shut off system
The emergency shut off system blocks off the high voltage current and
stops the fuel pump to minimize the risk of electrocution and fuel leakage
when a certain level of impact is detected by the impact sensor. If the
emergency shut off system activates, your vehicle will not restart. To
restart the hybrid system, contact your Lexus dealer.
Energy monitor/consumption screenYou can view the status of your hybrid system on the multi-information
display ( →P. 166) and the touch screen ( →P. 240). The following images
are examples only, and may vary slightly from actual conditions.
■ Energy monitor
● How to display on the touch screen:
Press .
Touch on the “Information” screen.
If the “Consumption” screen is displayed, touch .
● How to display on the multi-information display:
Push the “DISP” switch on the steering wheel several times to
select the energy monitor display.
STEP1
STEP2
STEP1
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To u c h s c r e e nMulti-information display
When the vehicle is
powered by the elec-
tric motor (traction
motor)
When the vehicle is
powered by the
gasoline engine
When the vehicle is
powered by both the
gasoline engine and the
electric motor (traction
motor)
When the vehicle is
charging the hybrid
battery (traction
battery)
When there is no
energy flow
Hybrid battery
(traction battery) statusLowFullLowFull
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■Consumption
Press .
Touch on the “Information” screen.
If the “Energy Monitor” screen is displayed, touch .
Fuel consumption in the past 30
minutes
Regenerated energy in the past
30 minutes
One symbol indicates 50 Wh. Up
to 4 symbols are shown.
Best past fuel consumption
Average fuel consumption
Cruising range
Hybrid warning message
A message is automatically displayed when a malfunction occurs in the
hybrid system or an improper operation is attempted. If a warning message is shown on
the multi-information display and
the touch screen, read the mes-
sage and follow the instructions.
(→P. 5 1 9 )
STEP1
STEP2
■Resetting the consumption data
Touching will reset the “Average fuel consumption”. Touching
will reset all the data (except the “Cruising Range”) on the “Consumption” screen.
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