
5487-2. Steps to take in an emergency
GS450h_300h_OM_OM30F00E_(EE)
If the electronic key does not operate properly
■Doors
Use the mechanical key ( →P. 1 3 5 )
in order to perform the following
operations:
Locks all the doors
Closes the windows and moon
roof (turn and hold)
*
Unlocks all the doors
Opens the windows and moon
roof (turn and hold)
*
*
: This setting must be customized at any authorized Lexus dealer or repairer, or another duly qualified and equipped professional.
■Tr u n k
Turn the mechanical key clockwise
to open.
If communication between the electronic key and vehicle is interrupted
(→ P. 155) or the electronic key cann ot be used because the battery is
depleted, the smart entry & start system and wireless remote control can-
not be used. In such cases, the d oors and trunk can be opened and the
hybrid system can be started by following the procedure below.
Locking and unlocking the doors, unlocking the trunk and key linked
functions
1
2
3
4

5497-2. Steps to take in an emergency
7
When trouble arises
GS450h_300h_OM_OM30F00E_(EE)
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 the power switch will
turn to ON mode.
When the smart entry & start system is
deactivated in customization 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 dealer or repairer, or another duly qualified and equipped professional.
■Stopping the hybrid system
Shift the shift lever to P and press the power sw itch 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. 4 5 1 )
■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 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. 2 1 8 )
■When the electronic key does not work properly
●Make sure that the smart entry & start syst em has not been deactivated in the customi-
zation setting. If it is off, turn the function on.
(Customizable features: →P. 5 8 1 )
●Check if battery-saving mode is set. If it is set, cancel the function. (→P. 1 5 4 )
Starting the hybrid system
1
2
3
4
3

551
7
7-2. Steps to take in an emergency
When trouble arises
GS450h_300h_OM_OM30F00E_(EE)
If the 12-volt battery is discharged
If you have a set of jumper (or booster) cables and a second vehicle with a 12-volt
battery, you can jump start your vehicle 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. 9 2 )
Open the hood ( →P. 4 1 7 ) , r e m o v e
the engine compartment covers
( → P. 421) and open the fuse box
cover.
Remove all of the clips.
Push the tabs on either side to
detach the lock and lift the lid off
while pulling the lock plate.
Open the exclusive jump starting
terminal cover.
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 dealer or repairer, or another duly
qualified and equipped professional.
1
2
1
2
3

5547-2. Steps to take in an emergency
GS450h_300h_OM_OM30F00E_(EE)
■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 components 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 will 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 replacing the 12-volt battery
●In some cases, it may not be possible to un lock 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 return to the mo de it was in before the 12-volt battery was
discharged. Before disconnecting the 12-volt 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.
WA R N I N G
■Avoiding 12-volt battery fires or explosions
Observe the following precautions to prevent accidentally igniting the flammable gas
that may be emitted from the 12-volt battery:
●Make sure each jumper cable is connected to the correct terminal and that it is not
unintentionally in contact with any other than the intended terminal.
●Do not allow the other end of the jumper cable connected to the “+” terminal to come
into contact with any other parts or metal surfaces in the area, such as brackets or
unpainted metal.
●Do not allow the + and - clamps of the jumper cables to come into contact with each
other.
●Do not smoke, use matches, cigarette lighters or allow open flame near the 12-volt
battery.