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1-3. Adjustable components (seats, mirrors, steering wheel)
1
Before driving
IS250C/350C_U
Front seat belt guideWhen fastening a front seat belt,
always ensure that it passes
through the seat belt guide.When entering or exiting the
rear seats, release the seat belt
from the guide.
Rear seat belt holder & guide
■ Rear seat belt holder
When the rear seat belts are not in
use, secure the belts in the holder
position. When in use, release the
belts from the holder position.
■ Rear seat belt guide
If the shoulder belt sits close to the occupant’s neck, secure the seat belt
in the guide position.
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1-3. Adjustable components (seats, mirrors, steering wheel)
1
Before driving
IS250C/350C_U
■Pregnant women
■People suffering illness
Obtain medical advice and wear the seat belt in the proper way.
■Child seat belt usage
The seat belts of your vehicle are principally designed for persons of adult size.
●Use a child restraint system appropriate for the child, until the child becomes
large enough to properly wear the vehicle's seat belt. (→P. 122)
●When the child becomes large enough to properly wear the vehicle's seat belt,
follow the instructions on P. 70 regarding seat belt usage.
■Replacing the belt after the pretensioner has been activated
If the vehicle is involved in multiple collisions, the pretensioner will activate for the
first collision, but will not activate for the second or subsequent collisions.
■Seat belt extender Obtain medical advice and wear the seat belt
in the proper way. (
→P. 7 0 )
Women who are pregnant should position
the lap belt as low as possible over the hips in
the same manner as other occupants. Extend
the shoulder belt completely over the shoul-
der and position the belt across the chest.
Avoid belt contact over the rounding of the
abdominal area.
If the seat belt is not worn properly, not only a
pregnant woman, but also the fetus could suf-
fer death or serious injury as a result of sud-
den braking or a collision.
If your seat belts cannot be fastened securely
because they are not long enough, a person-
alized seat belt extender is available from
your Lexus dealer free of charge.
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1-3. Adjustable components (seats, mirrors, steering wheel)
1
Before driving
IS250C/350C_U
CAUTION
■Seat belt damage and wear
●Do not damage the seat belts by allowing the belt, plate, or buckle to be jammed
in the door.
●Inspect the seat belt system periodically. Check for cuts, fraying, and loose parts.
Do not use a damaged seat belt until it is replaced. Damaged seat belts cannot
protect an occupant from death or serious injury.
●Ensure that the belt and tab are locked and the belt is not twisted.
If the seat belt does not function correctly, immediately contact your Lexus
dealer.
●Replace the seat assembly, including the belts, if your vehicle has been involved in
a serious accident, even if there's no obvious damage.
●Do not attempt to install, remove, modify, disassemble or dispose of the seat belts.
Have any necessary repairs carried out by your Lexus dealer. Inappropriate han-
dling of the pretensioner may prevent it from operating properly resulting in
death or serious injury.
■Using a seat belt extender
●Do not wear the seat belt extender if you can fasten the seat belt without the
extender.
●Do not use the seat belt extender when installing a child restraint system because
the belt will not securely hold the child restraint system, increasing the risk of
death or serious injury in the event of an accident.
●The personalized extender may not be safe on another vehicle, when used by
another person, or at a different seating position other than the one originally
intended.
NOTICE
■When using a seat belt extender
When releasing the seat belt, press on the buckle release button on the extender,
not on the seat belt.
This helps prevent damage to the vehicle interior and the extender itself.
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1-4. Opening and closing the windows and retractable hardtop
1
Before driving
IS250C/350C_U
Luggage coverThe luggage cover is used to ensure that there is enough space for the
retractable hardtop to be stored.
Proper installation of the luggage cover enables retractable hardtop
operation. Pull the board of the luggage
cover toward you to unhook the
hooks.
Pull the luggage cover further until
the tabs on the sides of the cover fit
securely into the holders on the
sides of the trunk.
Make sure the upper part of the
board is securely positioned in the
holders.
Fit the tabs on the bottom of the
luggage cover into the holders on
the floor of the trunk.
Make sure the lower part of the
board is securely positioned in the
holders on the floor.
STEP1
STEP2
STEP3
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1-4. Opening and closing the windows and retractable hardtop
IS250C/350C_U
NOTICE
■Precautions for opening/closing the retractable hardtop
●Before operating the retractable hardtop, make sure that the areas 2.3 ft. (70
cm) above the roof and 1.2 ft. (35 cm) behind the rear bumper is clear of obstruc-
tions.
●Do not put any items or packages on the package tray even if they are extremely
small.
●Do not store luggage on or allow anyone to sit on the retractable hardtop.
●When the outside temperature is -4°F (-20°C) or below or if the side windows
are frozen shut, do not open or close the retractable hardtop.
●Do not open the retractable hardtop if it is wet. Possible interior water damage,
water stains or mildew may result.
●When opening or closing the retractable hardtop, turn the rear window defog-
gers off.
●Do not leave the vehicle for an extended period of time with an open or close
operation incomplete.
●Do not open the trunk lid while the retractable hardtop is operating.
●If the retractable hardtop is operated repeatedly within a short period of time, the
motor protection circuit may activate, causing the roof switch to be disabled. In
this case, turn the “ENGINE START STOP” switch to ACCESSORY mode or off
and, after waiting for a while, perform the procedure again.
●Do not place anything on or under the luggage cover.
●The luggage cover should be attached securely. Protruding luggage may inter-
fere with the proper operation of the retractable hardtop, causing it to become
damaged.
■To prevent battery discharge
Do not operate the retractable hardtop repeatedly when the engine is off.
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IS250C/350C_U
1-6. Theft deterrent system
Engine immobilizer system
■System maintenance
The vehicle has a maintenance-free type engine 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 to the security system (key
with a built-in transponder chip) of another vehicle
The vehicle's keys have built-in tran sponder chips that prevent the engine
from starting if the 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.
The indicator light flashes after
the “ENGINE START STOP”
switch has been turned OFF to
indicate that the system is oper-
ating.
The indicator light stops flashing
after the “ENGINE START
STOP” switch has been turned
to ACCESSORY or IGNITION
ON mode to indicate that the
system has been canceled.
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1-7. Safety information
1
Before driving
IS250C/350C_U
Airbag system componentsYour vehicle is equipped with ADVANCED AIRBAGS designed based
on the US motor vehicle safety standards (FMVSS208). The airbag sen-
sor assembly (ECU) controls airbag deployment based on information
obtained from the sensors etc. shown in the system components diagram
above. This information includes crash severity and occupant informa-
tion. As the airbags deploy, a chemical reaction in the inflators quickly fills
the airbags with non-toxic gas to help restrain the motion of the occu-
pants. Knee airbags
Front passenger airbag
“AIR BAG ON” and “AIR BAG
OFF” indicator lights
Side airbags
Side airbag sensors
Seat belt pretensioners and
force limiters
SRS warning light
Driver airbag
Driver's seat belt buckle switch
Driver's seat position sensor
Front passenger’s seat belt
buckle switch
Airbag sensor assembly
Front passenger occupant
classification system
(ECU and sensors)
Front airbag sensors
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1-7. Safety information
IS250C/350C_U
■SRS warning light
This warning light system monitors the airbag sensor assembly, front airbag sensors,
side airbag sensor assemblies, driver's seat position sensor, driver's seat belt buckle
switch, front passenger occupant classification system (ECU and sensors), “AIR
BAG ON” indicator light, “AIR BAG OFF” indicator light, front passenger’s seat
belt buckle switch, seat belt pretensioner assemblies, airbags, interconnecting wir-
ing and power sources. (→P. 4 9 2 )
■If the SRS airbags deploy (inflate)
●Bruising and slight abrasions may result from contact with a deploying (inflating)
SRS airbag.
●A loud noise and white powder will be emitted.
●Parts of the airbag module (steering wheel, airbag cover and inflator) as well as
the front seats may be hot for several minutes. The airbag itself may also be hot.
●The windshield may crack.
●For Safety Connect subscribers, if the SRS airbags deploy or in the event of a
severe rear-end collision, the system is designed to send an emergency call to
the response center, notifying them of the vehicle’s location (without needing to
push the “SOS” button) and an agent will attempt to speak with the occupants
to ascertain the level of emergency and assistance required. If the occupants
are unable to communicate, the agent automatically treats the call as an emer-
gency and helps to dispatch the necessary emergency services. ( →P. 388)
■SRS airbag deployment conditions (SRS front airbags)
●The SRS front airbags will deploy in the event of an impact that exceeds the
set threshold level (the level of force corresponding to an approximately 12 -
18 mph [20 - 30 km/h] frontal collision with a fixed wall that does not move or
deform).
However, this threshold velocity will be considerably higher if the vehicle strikes
an object, such as a parked vehicle or sign pole, which can move or deform on
impact, or if the vehicle is involved in an underride collision (e.g. a collision in
which the front of the vehicle “underrides”, or goes under, the bed of a truck, etc.).