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811-2. Hybrid system
1
For safety and security
IS300h_EE(OM53D56E)
■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 an d stops automatically. 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 outside source. However, if the vehicle is left parked for
a long time the hybrid battery will slowly discharge. For this reason, be sure to drive the
vehicle at least once every few months for at least 30 minutes or 16 km (10 miles). If the
hybrid battery becomes fully discharged and you are unable to jump-start the vehicle
with a 12-volt battery, contact any authorized Lexus dealer or repairer, or another duly
qualified and equipped professional.
●If the shift lever is in N, the hybrid battery (traction battery) will not be charged. Always
shift the shift lever to P when the vehicle is stopped. When driving in heavy traffic, oper-
ate the vehicle with the shift lever in D or S to avoid discharging the battery.
■Charging the 12-volt battery
→ P. 5 6 8
The EV indicator comes on when the vehicle is
driven using only the electric motor (traction
motor) or the gasoline engine is stopped.
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831-2. Hybrid system
1
For safety and security
IS300h_EE(OM53D56E)
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 operatin g. Obey the caution labels attached to
the vehicle.
Caution label
Po w e r c o n t ro l u n i t
Electric motor (traction motor)
Hybrid battery (traction battery) Service plug
High voltage cables (orange)
Air conditioning compressor1
2
3
4
5
6
7
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851-2. Hybrid system
1
For safety and security
IS300h_EE(OM53D56E)
■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 any authorized Lexus dealer or repairer, or another
duly qualified and equipped professional.
■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. 5 2 3 )
go off. If there is only a small amount of fu el, the hybrid system may not be able to start.
(The minimum amount of fuel to add to make the low fuel level warning light go out is
about 10 L [2.7 gal., 2.2 Imp. gal.], when the vehicle is on a level surface. This value may
vary when the vehicle is on a slope.)
■Electromagnetic waves
●High voltage parts and cables on hybrid vehicles 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 lim ited service life. The lifespan of the hybrid
battery (traction battery) can change in accordance with driving style and driving condi-
tions.
■Declaration of conformity
This model conforms to hydrogen emissions according to regulation ECE100 (Battery
electric vehicle safety).
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871-2. Hybrid system
1
For safety and security
IS300h_EE(OM53D56E)
CAUTION
■Road accident cautions
Observe the following precautions to reduce the risk of death or serious injury:
●Pull your vehicle off the road, apply the parking 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 outside your vehicle, an electric shock may
occur. Never touch exposed electric wires.
●If a fluid leak occurs, do not touch the fluid 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 immediate 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 electric 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 electricity. This may cause an electricity leakage
leading to a fire. ( →P. 5 1 4 )
●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.
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891-2. Hybrid system
1
For safety and security
IS300h_EE(OM53D56E)
NOTICE
■Hybrid battery air vent
●Do not put foreign objects near the air vent. The hybrid battery (traction battery) may
overheat and be damaged.
●Clean the air vent regularly to prevent the hybrid battery (traction battery) from over-
heating.
●Do not wet or allow foreign substances to enter the air vent 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 (traction battery), the battery may be damaged.
Have the vehicle inspected by any authorized Lexus dealer or repairer, or another
duly qualified and equipped professional.
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90
IS300h_EE(OM53D56E)1-3. Theft deterrent system
The indicator light flashes after the
power switch has been turned off to
indicate that the system is operating.
The indicator light stops flashing after
the power switch has been turned to
ACCESSORY or ON mode to indi-
cate that the system has been canceled.
■System maintenance
The vehicle has a maintenance-free type immobilizer system.
■Conditions that may cause the system to malfunction
●If the grip portion of the key is
in contact with a metallic object
●If the key is in close proximity to or touching a key registered to the security system (key
with a built-in transponder chip) of another vehicle
Immobilizer system
The vehicle’s keys have built-in transp onder chips that prevent the hybrid sys-
tem from starting if a key has not been previously registered in the vehicle’s
on-board computer.
Never leave the keys inside the vehicle when you leave the vehicle.
This system is designed to help prev ent vehicle theft but does not guarantee
absolute security against all vehicle thefts.
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911-3. Theft deterrent system
1
For safety and security
IS300h_EE(OM53D56E)
■Certifications for the immobilizer system
Page 93 of 628
931-3. Theft deterrent system
1
For safety and security
IS300h_EE(OM53D56E)