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IS250C/350C_U
If the electronic key does not operate properly
Locking and unlocking the doors, unlocking the trunk
Use the mechanical key built in to the electronic keys to operate the
doors. (→ P. 2 9 )
Doors Remove the cover on the driver’s
door handle.
Locks both side doors
Unlocks the door
Tu r n i n g t h e k e y r e a r w a r d u n l o c k s
the driver's door. Turning the key
once again unlocks the passenger’s
door.
If communication between the electronic key and vehicle is interrupted
(→ P. 36) or the electronic key cannot be used because the battery is
depleted, the smart access system with push-button start and wireless
remote control cannot be used. In such cases, the doors and trunk can be
opened or the engine can be started by following the procedure below.
STEP1
STEP2
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5-2. Steps to take in an emergency
IS250C/350C_UAfter the operation is completed,
reinstall the cover.
Hook the upper claw of the cover
onto the upper catch on the vehi-
cle side, and then push on the
lower side of the cover.
Make sure that the lower claw of
the cover is securely fastened to
the lower catch on the vehicle side.
If the cover is not securely
attached, it may fall off while driv-
ing.
Tr u n k
Remove the cover using a
mechanical key.
Turn the mechanical key clock-
wise to open.
STEP3
STEP1
STEP2
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Starting the engine
Shift the shift lever to P and apply the brakes.Touch the Lexus emblem side of
the electronic key to the
“ENGINE START STOP” switch.
An alarm will sound to indicate that
the start function cannot detect the
electronic key that is touched to
the “ENGINE START STOP”
switch if any of the doors is opened
and closed while the key is touched
to the switch.
Press the “ENGINE START STOP” switch within 10 seconds
after the buzzer sounds, keeping the brake pedal depressed.
In the event that the engine still cannot be started, contact your Lexus
dealer.
STEP1
STEP2
STEP3
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5-2. Steps to take in an emergency
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■Stopping the engine
Shift the shift lever to P and press the “ENGINE START STOP” switch as you nor-
mally do when stopping the engine.
■Replacing the key battery
As the above procedure is a temporary measure, it is recommended that the elec-
tronic key battery be replaced immediately when the battery depletes. (→P. 4 4 9 )
■Changing “ENGINE START STOP” switch modes
Within 10 seconds of the buzzer sounding, release the brake pedal and press the
“ENGINE START STOP” switch.
The engine does not start and modes w ill be changed each time the switch is
pressed. ( →P. 1 4 8 )
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If the vehicle battery is discharged
The following procedures may be used to start the engine if the vehicle’s
battery is discharged.
You can call your Lexus dealer, or qualified repair shop.
If you have a set of jumper (or booster) cables and a second vehicle
with a 12-volt battery, you can jump start your Lexus following the steps
below.
Remove the engine compartment covers. ( →P. 4 1 8 )
Connecting the jumper cables.
Positive (+) battery terminal on your vehicle
Positive (+) battery terminal on the second vehicle
Negative (-) battery terminal on the second vehicle
Connect the jumper cable to ground on your vehicle as shown in the
illustration. Start the engine of the second vehicle. Increase the engine
speed slightly and maintain at that level for approximately 5
minutes to recharge the battery of your vehicle.
Open and close any of the doors with the “ENGINE START
STOP” switch OFF.
STEP1
STEP2
STEP3
STEP4
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5-2. Steps to take in an emergency
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■Avoiding a discharged battery
●Turn off the headlights and the audio system while the engine is off.
●Turn off any unnecessary electrical components when the vehicle is running at a
low speed for an extended period, such as in heavy traffic, etc.
■Charging the battery
The electricity stored in the battery will discharge gradually even when the vehi-
cle is not in use, due to natural discharge and the draining effects of certain
electrical appliances. If the vehicle is left for a long time, the battery may dis-
charge, and the engine may be unable to start. (The battery recharges automat-
ically during driving.)
■When the battery is removed or discharged
Make sure that the key is not inside the vehicle when recharging or replacing the
battery. The key may be locked in the vehicle if the alarm is activated. (→P. 1 0 1 )
Maintain the engine speed of the second vehicle and turn the
“ENGINE START STOP” switch to IGNITION ON mode,
then start the vehicle’s engine.
Once the vehicle’s engine has started, remove the jumper
cables in the exact reverse order in which they were con-
nected.
Once the engine starts, have the vehicle checked at your Lexus dealer
as soon as possible.STEP5
STEP6
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CAUTION
■Avoiding battery fires or explosions
Observe the following precautions to prevent accidentally igniting the flammable
gas that may be emitted from the battery.
●Make sure the jumper cable is connected to the correct terminal and that it is not
unintentionally in contact with any part other than the intended terminal.
●Do not allow the jumper cables to come into contact with the “+” and “-” termi-
nals.
●Do not allow open flame or use matches, cigarette lighters or smoke near the
battery.
■Battery precautions
The battery contains poisonous and corrosive acidic electrolyte, while related parts
contain lead and lead compounds. Observe the following precautions when han-
dling the battery.
●When working with the battery, always wear safety glasses and take care not to
allow any battery fluids (acid) to come into contact with skin, clothing or the vehi-
cle body.
●Do not lean over the battery.
●In the event that battery fluid comes into contact with the skin or eyes, immedi-
ately wash the affected area with water and seek medical attention.
Place a wet sponge or cloth over the affected area until medical attention can be
received.
●Always wash your hands after handling the battery support, terminals, and other
battery-related parts.
●Do not allow children near the battery.
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NOTICE
■To prevent damaging the vehicle
Do not pull- or push-start the vehicle, because the three-way catalytic converter
may overheat and become a fire hazard.
■When handling jumper cables
Be careful that the jumper cables do not become tangled in the cooling fan or any
of the belts when connecting or disconnecting them.