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If you lose your keys
New genuine Lexus keys can be made by your Lexus dealer using the other
key and the key number stamped on your key number plate.
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If the electronic key does not operate properly
Locking and unlocking the doors, unlocking the trunk and key linked functions
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 all the doors
Closes the windows and moon
roof (turn and hold)
Unlocks the door
Turning the key rearward unlocks
the driver's door. Turning the key
once again unlocks the other
doors.
Opens the windows and moon
roof (turn and hold)
If communication between the electronic key and vehicle is interrupted
(→ P. 37) 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
IS350/250_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
Turn the mechanical key clock-
wise to open.
STEP3
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Changing “ENGINE START STOP” switch modes and starting the engine
Automatic transmissionShift 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.
To change “ENGINE START STOP” switch modes: Within 10
seconds of the buzzer sounding, release the brake pedal and
press the “ENGINE START STOP” switch. Modes can be
changed each time the switch is pressed.
(→P. 141)
To start the engine: Press the “ENGINE START STOP” switch
within 10 seconds after the buzzer sounds, keeping the brake
pedal depressed.
STEP1
STEP2
STEP3
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5-2. Steps to take in an emergency
IS350/250_UManual transmission
Shift the shift lever to N and depress the clutch pedal.
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.
To change “ENGINE START ST OP” switch modes: Within 10
seconds of the buzzer sounding, release the clutch pedal and
press the “ENGINE START STOP” switch. Modes can be
changed each time the switch is pressed.
(→ P. 141)
To start the engine: Press the “ENGINE START STOP” switch
within 10 seconds after the buzzer sounds, keeping the clutch
pedal depressed.
In the event that the engine still cannot be started, contact your Lexus
dealer.
STEP1
STEP2
STEP3
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■Stopping the engine
For vehicles with an automatic transmission: Shift the shift lever to P and press the
“ENGINE START STOP” switch as you normally do when stopping the engine.
For vehicles with a manual transmission: Shift the shift lever to N position and press
the “ENGINE START STOP” switch as you normally 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 3 3 )
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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 a 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. 399)
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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■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 vehicle
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 discharge, and the
engine may be unable to start. (The battery recharges automatically during driving.)
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.
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