Page 629 of 692
6298-2. Steps to take in an emergency
8
When trouble arises
IS300h_EE(OM53D89E)
Ensure that the shift lever is in P and depress the brake pedal.
Touch the Lexus emblem side of the
electronic key to the power switch.
When the electronic key is detected, a buzzer sounds and th e power switch will
turn to ON mode.
When the smart entry & start system is deactivated in custom ization setting, the
power switch will turn to ACCESSORY
mode.
Firmly depress the brake pedal and check that is shown on the multi-
information display.
Press the power switch.
In the event that the hybrid system still cannot be started, contact any authorized
Lexus retailer or Lexus authorized repairer, or any reliable repairer.
Starting the hybrid system
1
2
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Page 630 of 692

6308-2. Steps to take in an emergency
IS300h_EE(OM53D89E)
■Stopping the hybrid system
Shift the shift lever to P and pr ess the power switch as you normally do when stopping the
hybrid system.
■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. 549)
■Alarm (if equipped)
Using the mechanical key to lock th e 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 power switch modes
Release the brake pedal and press the power switch in step above. The hybrid system does not start and modes will be changed each time the switch is
pressed. ( P. 220)
■When the electronic key does not work properly
●Make sure that the smart entry & start system has not been deactivated in the
customization setting. If it is off, turn the function on.
(Customizable features: P. 657)
●Check if battery-saving mode is set. If it is set, cancel the function. (P. 158)
WARNING
■When using the mechanical key and operating the power windows or 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 op erate the mechanical key. It is possible for children and other passengers to get caught in the power window or moon roof.
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Page 631 of 692
6318-2. Steps to take in an emergency
8
When trouble arises
IS300h_EE(OM53D89E)
If you have a set of jumper (or booster) cables and a second vehicle with a 12-volt
battery, you can jump start your ve hicle by following the steps below.
Confirm that the electronic key is
being carried.
When connecting the jumper (or booster) cables, depending on the situa-
tion, the alarm may activate and doors
locked. (P. 94)
Open the hood ( P. 513) and fuse
box cover.
Remove the clips.
Push the tabs on either side to
detach the lock and lift the lid off
while pulling the lock plate.
If the 12-volt battery is discharged
The following procedures may be used to start the hybrid system if the 12-volt
battery is discharged.
You can also call any authorized Lexus retailer or Lexus authorized repairer,
or any reliable repairer.
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2
1
2
Page 633 of 692

6338-2. Steps to take in an emergency
8
When trouble arises
IS300h_EE(OM53D89E)
Maintain the engine speed of the second vehicle and start the hybrid system
of your vehicle by turning the power switch to ON mode.
Make sure the “READY” indicator comes on. If the indicator does not come
on, contact any authorized Lexus retailer or Lexus authorized repairer, or any
reliable repairer.
Once the hybrid system has started, remove the jumper cables in the exact
reverse order from which they were connected.
Once the hybrid system starts, have the vehicle inspected at any authorized
Lexus retailer or Lexus authorized repair er, or any reliable repairer as soon as
possible.
■Starting the hybrid system when the 12-volt battery is discharged
The hybrid system cannot be started by push-starting.
■To prevent 12-volt battery discharge
●Turn off the headlights and the audio system while the hybrid system is off.
●Turn off any unnecessary electrical componen ts when the vehicle is running at a low
speed for an extended period , such as in heavy traffic.
■Charging the 12-volt battery
The electricity stored in the 12-volt battery w ill discharge gradually even when the vehicle
is not in use, due to natural discharge and the draining effects of certain electrical appli-
ances. If the vehicle is left for a long time, the 12-volt battery may discharge, and the hybrid system may be unable to start. (The 12-volt battery recharges automatically while
the hybrid system is operating.)
■When recharging or repl acing the 12-volt battery
●In some cases, it may not be possible to unlock the doors using the smart entry & start
system when the 12-volt battery is discharged. Use the wireless remote control or the
mechanical key to lock or unlock the doors.
●The hybrid system may not start on the first attempt after the 12-volt battery has
recharged but will start normally after the second attempt. This is not a malfunction.
●The power switch mode is memorized by the vehicle. When the 12-volt battery is reconnected, the system will retu rn to the mode it was in before the 12-volt battery was
discharged. Before disconnecting the 12-vol t battery, turn the power switch off.
If you are unsure what mode the power switch was in before the 12-volt battery dis- charged, be especially careful when reconnecting the 12-volt battery.
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Page 659 of 692
659
9
9-2. Customization
Vehicle specifications
IS300h_EE(OM53D89E)
■Door lock ( P. 144, 151, 628)
■Smart entry & start system and wireless remote control (P. 144, 151)
FunctionDefault settingCustomized setting
Unlocking using a mechanical key
All doors
unlocked in one step
Driver’s door unlocked in one step,
all doors unlocked in
two steps
—O
Speed-detecting automatic door lock functionOnOffOO
Shifting gears to position other
than P locks all doorsOffOnOO
Shifting gears to P unlocks all
doorsOffOnOO
Opening driver’s door unlocks all doorsOnOffOO
Locking/unlocking of the trunk
when all doors are locked/
unlocked
OnOff—O
12
FunctionDefault settingCustomized setting
Operation signal (Emergency flashers)OnOffOO
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
Welcome light illumination con-
trolOnOff—O
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Page 661 of 692
661
9
9-2. Customization
Vehicle specifications
IS300h_EE(OM53D89E)
■Outside rear view mirrors ( P. 189)
*:If equipped
■Power windows (P. 193)
■Moon roof* (P. 197)
*:If equipped
FunctionDefault settingCustomized setting
Automatic mirror folding and extending operation*
Linked to the
locking/unlock-
ing of the doors
Off
—OLinked to operation of the power switch
12
FunctionDefault settingCustomized setting
Mechanical key linked operationOffOn—O
Wireless remote control linked
operationOffOn—O
Wireless remote control linked
operation signal (buzzer)OnOff—O
12
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
Wireless remote control linked
operation signal (buzzer)OnOff—O
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Page 664 of 692
6649-2. Customization
IS300h_EE(OM53D89E)
■Illumination ( P. 481)
FunctionDefault settingCustomized setting
Time elapsed before the interior
lights turn off15 seconds
Off
OO7.5 seconds
30 seconds
Operation after the power switch is turned offOnOff—O
Operation when the doors are
unlockedOnOff—O
Operation when you approach
the vehicle with the electronic key on your personOnOff—O
Inside door handle lightsOnOff—O
Time elapsed before the outer
foot lights turn off15 seconds
Off
OO7.5 seconds
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 switch
OnOff—O
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Page 668 of 692

668
IS300h_EE(OM53D89E)
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 retailer or Lexu s authorized repairer, or any reliable
repairer. ( P. 140)
●If you lose your electronic keys, the risk of vehicle theft increases significantly.
Contact any authorized Lexus retailer or Lexus authorized repairer, or any
reliable repairer immediately. ( P. 143)
●Is the electronic key battery weak or depleted? (P. 549)
●Is the power switch in ON mode?
When locking the doors, turn the power switch off. (P. 220)
●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 du e to the condition of the radio wave.
( P. 159)
●Is the child-protector lock set?
The rear door cannot be opened from in side the vehicle when the lock is set.
Open the rear door from outside and then unlock the child-protector lock.
( P. 148)
If you have a problem, check the following before contacting any authorized
Lexus retailer or Lexus authorized re pairer, or any reliable repairer.
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