Page 526 of 588

5268-2. Steps to take in an emergency
IS250_EE(OM53C51E)
■Stopping the engine
Shift the shift lever to P and press the engine 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 electronic
key battery be replaced immediately when the battery is depleted. (→P. 4 4 2 )
■Alarm (if equipped)
Using the mechanical key to lock the doors will not set the alarm system.
If a door is unlocked using the mechanical key when the alarm system is set, the alarm
may be triggered.
■Changing engine switch modes
Release the brake pedal and press the engine switch in step above.
The engine does not start and modes will be changed each time the switch is pressed.
(→P. 1 9 3 )
■When the electronic key does not work properly
●Make sure that the smart entry & start system has not been deactivated in the customi-
zation setting. If it is off, turn the function on.
(Customizable features →P. 551)
●Check if battery-saving mode is set. If it is set, cancel the function. (→P. 131)
CAUTION
■When using the mechanical key and operating the power windows and moon roof
Operate the power window or moon roof after checking to make sure that there is no
possibility of any passenger having any of their body parts caught in the window or
moon roof.
Also, do not allow children to operate the mechanical key. It is possible for children and
other passengers to get caught in power window and moon roof.
3
Page 529 of 588

5298-2. Steps to take in an emergency
8
When trouble arises
IS250_EE(OM53C51E)
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 of your vehicle with the engine switch off.
Maintain the engine speed of the second vehicle and start the engine of your
vehicle by turning the engine switch to IGNITION ON mode.
Once the vehicle’s engine has started, remove the jumper cables in the exact
reverse order from which they were connected.
Once the engine starts, have the vehicle inspected at any authorized Lexus
dealer or repairer, or another duly qualified and equipped professional as soon
as possible.
■Starting the engine when the battery is discharged
The engine cannot be started by push-starting.
■To prevent battery discharge
●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.
■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.)
■When recharging or replacing the battery
●For vehicles with an alarm: 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. 8 5 )
●In some cases, it may not be possible to unlock the doors using the smart entry & start
system when the battery is discharged. Use the wireless remote control or the mechan-
ical key to lock or unlock the doors.
●The engine may not start on the first attempt after the battery has recharged but will
start normally after the second attempt. This is not a malfunction.
●The engine switch mode is memorized by the vehicle. When the battery is recon-
nected, the system will return to the mode it was in before the battery was discharged.
Before disconnecting the battery, turn the engine switch off.
If you are unsure what mode the engine switch was in before the battery discharged, be
especially careful when reconnecting the battery.
4
5
6
7
Page 554 of 588
5549-2. Customization
IS250_EE(OM53C51E)
■Door lock (→P. 118, 125, 524)
■Smart entry & start system and wireless remote control (→P. 118, 125)
FunctionDefault settingCustomized setting
Unlocking using a mechanical
keyAll doors
unlocked in
one stepDriver’s door
unlocked in one
step, all doors
unlocked in two
steps
——O
Speed-detecting automatic door
lock functionOnOffO—O
Shifting gears to position other
than P locks all doorsOffOnO—O
Shifting gears to P unlocks all
doorsOffOnO—O
Opening driver's door unlocks
all doorsOnOffO—O
Locking/unlocking of the trunk
when all doors are locked/
unlocked
OnOff——O
123
FunctionDefault settingCustomized setting
Operation signal
(Emergency flashers)OnOffO—O
Time elapsed before automatic
door lock function is activated if
door is not opened after being
unlocked
30 seconds
60 seconds
——O120 seconds
Open door warning buzzerOnOff——O
123
Page 555 of 588
555
9 9-2. Customization
Vehicle specifications
IS250_EE(OM53C51E)
■Smart entry & start system (→P. 118, 125, 130)
*: If equipped
■Wireless remote control (→P. 118, 125)
■Driving position memory* (→P. 1 5 1 )
*: If equipped
FunctionDefault settingCustomized setting
Smart entry & start systemOnOffO—O
Smart door unlocking*All the doorsDriver's doorO—O
Number of consecutive door
lock operations*As many as
desired2 times——O
123
FunctionDefault settingCustomized setting
Wireless remote controlOnOff——O
Unlocking operation
All doors
unlocked in
one stepDriver's door
unlocked in one
step, all doors
unlocked in two
steps
O—O
Trunk unlocking operationPress and hold
(short)
One short press
——O
Push twice
Press and hold
(long)
Off
123
FunctionDefault settingCustomized setting
Driver's seat movement when
exiting the vehicleStandardOffO—OPa r t i a l
Doors linked to the driving posi-
tion memory recall functionDriver's doorAll doors——O
123
Page 556 of 588
5569-2. Customization
IS250_EE(OM53C51E)
■Outside rear view mirrors (→P. 1 6 3 )
*: If equipped
■Powe r w i n d ows (→P. 1 6 7 )
■Moon roof* (→P. 1 7 0 )
*: If equipped
FunctionDefault settingCustomized setting
Automatic mirror folding and
extending operation*
Linked to the
locking/
unlocking of
the doorsOff
——OLinked to operation
of the engine switch
123
FunctionDefault settingCustomized setting
Mechanical key linked operationOffOn——O
Wireless remote control linked
operationOffOn——O
123
FunctionDefault settingCustomized setting
Mechanical key linked operationOffOn——O
Linked operation of components
when mechanical key is used
(open only)Slide onlyTilt only——O
Wireless remote control linked
operationOffOn——O
Linked operation of components
when wireless remote control is
used (open only)Slide onlyTilt only——O
123
Page 559 of 588
559
9 9-2. Customization
Vehicle specifications
IS250_EE(OM53C51E)
■Illumination (→P. 3 8 9 )
FunctionDefault settingCustomized setting
Time elapsed before the interior
lights turn off15 seconds
Off
O—O7. 5 s e c o n d s
30 seconds
Operation after the engine
switch is turned offOnOff——O
Operation when the doors are
unlockedOnOff——O
Operation when you approach
the vehicle with the electronic
key on your person
OnOff——O
Inside door handle lightsOnOff——O
Time elapsed before the outer
foot lights turn off15 seconds
Off
O—O7. 5 s e c o n d s
30 seconds
Operation of the outer foot lights
when you approach the vehicle
with the electronic key on your
person
OnOff——O
Operation of the outer foot lights
when the doors are unlocked
with the power door lock switchOnOff——O
123
Page 560 of 588

5609-2. Customization
IS250_EE(OM53C51E)
■Vehicle customization
●When the speed-detecting automatic door lock and shift-linked automatic door lock
are both on, the door lock operates as follows.
• When shifting the shift lever to any position other than P, all the doors will be locked.
• If the vehicle is started with all doors locked, the speed-detecting automatic door
lock will not operate.
• If the vehicle is started with any door unlocked, the speed-detecting automatic door
lock will operate.
●When the smart entry & start system is off, the entry unlock function cannot be custom-
ized.
●When the doors remain closed after unlocking the doors and the timer activated auto-
matic door lock function activates, signals will be generated in accordance with the
operation buzzer volume and operational signal (Emergency flashers) function set-
tings.
■When customizing using the Remote Touch or Lexus Display Audio controller
Stop the vehicle in a safe place, apply the parking brake, and shift the shift lever to P. Also,
to prevent battery discharge, leave the engine running while customizing the features.
CAUTION
■During customization
As the engine needs to be running during customization, ensure that the vehicle is
parked in a place with adequate ventilation. In a closed area such as a garage, exhaust
gases including harmful carbon monoxide (CO) may collect and enter the vehicle. This
may lead to death or a serious health hazard.
NOTICE
■During customization
To prevent battery discharge, ensure that the engine is running while customizing fea-
tures.
Page 564 of 588

564
IS250_EE(OM53C51E)What to do if... (Troubleshooting)
What to do if... (Troubleshooting)
●If you lose your mechanical keys, new genuine mechanical keys can be made
by any authorized Lexus dealer or repairer, or another duly qualified and
equipped professional. (→P. 114)
●If you lose your electronic keys, the risk of vehicle theft increases significantly.
Contact any authorized Lexus dealer or repairer, or another duly qualified
and equipped professional immediately. (→P. 1 1 7 )
●Is the electronic key battery weak or depleted? (→P. 4 4 2 )
●Is the engine switch in IGNITION ON mode?
When locking the doors, turn the engine switch off. (→P. 1 9 3 )
●Is the electronic key left inside the vehicle?
When locking the doors, make sure that you have the electronic key on your
person.
●The function may not operate properly due to the condition of the radio wave.
(→P. 1 3 2 )
●Is the child-protector lock set?
The rear door cannot be opened from inside the vehicle when the lock is set.
Open the rear door from outside and then unlock the child-protector lock.
(→P. 1 2 2 )
If you have a problem, check the following before contacting any authorized
Lexus dealer or repairer, or another duly qualified and equipped professional.
The doors cannot be locked, unlocked, opened or closed
You lose your keys
The doors cannot be locked or unlocked
The rear door cannot be opened