Page 413 of 600

413
6-3. Do-it-yourself maintenance
6
Maintenance and care
GS450h_300h_OM_OM30F92E_(EE) The meanings of each caution symbol on the top of the 12-volt battery are as fol-
lows:
■Before recharging
When recharging, the 12-volt battery produces hydrogen gas which is flammable and
explosive. Therefore, observe the following precautions before recharging:
●If recharging with the 12-volt battery installed on the vehicle, be sure to disconnect the
ground cable.
●Make sure the power switch on the charger is off when connecting and disconnecting
the charger cables to the 12-volt battery.
■After recharging/reconnecting the 12-volt battery
●The hybrid system may not start. Follow the procedure below to initialize the system.
Shift the shift lever to P.
Open and close any of the doors.
Restart the hybrid system.
●Unlocking the doors using the smart entry & start system may not be possible immedi-
ately after reconnecting the 12-volt battery. If this happens, use the wireless remote
control or the mechanical key to lock/unlock the doors.
●Start the hybrid system with the power switch in ACCESSORY mode. The hybrid sys-
tem may not start with the power switch turned off. However, the hybrid system will
operate normally from the second attempt.
●The power switch mode is recorded by the vehicle. If the 12-volt battery is reconnected,
the vehicle will return the power switch mode to the status it was in before the 12-volt
battery was disconnected. Make sure to tu rn off the power switch before disconnect
the 12-volt battery. Take extra care when connecting the 12-volt battery if the power
switch mode prior to discharge is unknown.
If the system will not start even after multiple attempts at all methods above, contact any
authorized Lexus retailer or Lexus author ized repairer, or any reliable repairer.
Caution symbols
No smoking, no naked
flames, no sparks12-volt battery acid
Shield eyesNote operating instructions
Keep away from childrenExplosive gas
1
2
3
Page 435 of 600
435
6
6-3. Do-it-yourself maintenance
Maintenance and care
GS450h_300h_OM_OM30F92E_(EE)
Electronic key battery
●Flathead screwdriver
● Small flathead screwdriver
● Lithium battery CR2032
Take out the mechanical key.
Remove the cover.
To prevent damage to the key, cover the
tip of the screwdriver with a rag.
Remove the battery cover.
To prevent damage to the key, cover the
tip of the screwdriver with a rag.
Replace the battery with a new one if it is depleted.
You will need th e following items:
Replacing the battery
1
2
3
Page 436 of 600

4366-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30F92E_(EE) Remove the depleted battery.
Insert a new battery with the “+” termi-
nal facing up.
■Use a CR2032 lithium battery
●Batteries can be purchased at any authorized Lexus retailer or Lexus authorized
repairer, or any reliable repairer, local el
ectrical appliance shops or camera stores.
●Replace only with the same or equivalent type recommended by the manufacturer.
●Dispose of used batteries according to the local laws.
■When the card key battery needs to be replaced (if equipped)
The battery for the card key is available only at Lexus dealers. Your Lexus dealer can
replace the battery for you.
■If the electronic key battery is depleted
The following symptoms may occur:
●The smart entry & start system and wireless remote control will not function properly.
●The operational range will be reduced.
4
WARNING
■Removed battery and other parts
These parts are small and if swallowed by a child, they can cause choking. Keep away
from children. Failure to do so could result in death or serious injury.
■Lithium battery precautions
CAUTION
RISK OF EXPLOSION IF BATTERY IS REPLACED BY AN INCORRECT TYPE.
DISPOSE OF USED BATTERIES ACCORDING TO THE INSTRUCTIONS
NOTICE
■For normal operation after replacing the battery
Observe the following precautions to prevent accidents:
●Always work with dry hands.
Moisture may cause the battery to rust.
●Do not touch or move any other component inside the remote control.
●Do not bend either of the battery terminals.
Page 451 of 600

451
7When trouble arises
GS450h_300h_OM_OM30F92E_(EE) 7-1. Essential information
Emergency flashers ..................452
If your vehicle has to be stopped in an
emergency.................................453 7-2. Steps to take in an
emergency
If your vehicle needs to be towed................................ 454
If you think something is wrong....................................... 459
If a warning light turns on or a warning buzzer
sounds..........................................460
If a warning message is displayed ................................ 466
If you have a flat tire (vehicles with spare tire) ......498
If you have a flat tire (vehicles without spare
tire)................................................509
If the hybrid system will not start................................ 523
If the parking brake cannot be released................. 525
If the electronic key does not operate properly ............. 527
If the 12-volt battery is discharged .................................530
If your vehicle overheats .........535
If the vehicle becomes stuck ............................................. 542
Page 493 of 600

493
7-2. Steps to take in an emergency
7
When trouble arises
GS450h_300h_OM_OM30F92E_(EE)
Interior
buzzerExteriorbuzzerWarning messageDetails/Actions
Once
The electronic key is not detected
when an attempt is made to start the hybrid system. Start the hybrid system with the
electronic key present.
Once3 times
The electronic key was carried out-
side the vehicle and a door other
than the driver’s door was opened
and closed while the power switch
was in a mode other than off. Bring the electronic key back
into the vehicle.
The driver’s door was opened and
closed while the electronic key was
not in the vehicle, the shift lever was
in P and the power switch was not
turned off. Turn the power switch off or
bring the electronic key back
into the vehicle.
OnceCon-
tinuous
An attempt was made to exit the
vehicle with the electronic key and
lock the doors without first turning
the power switch off when the shift
lever was in P.Turn the power switch off and
lock the doors again.
(Flashes)
(Flashes)
(Displayed alternately)
(Flashes)
Page 494 of 600
4947-2. Steps to take in an emergency
GS450h_300h_OM_OM30F92E_(EE)
9
times
An attempt was made to drive when
the regular key was not inside the
vehicle. Confirm that the electronic key
is inside the vehicle.
Con-
tinuous
The driver’s door was opened when
the shift lever was not in P and the
power switch was not turned off. Shift the shift lever to P.
Con-
tinuousCon-
tinuous
The driver’s door was opened and
closed while the electronic key was
not in the vehicle, the shift lever was
not in P and the power switch was
not turned off.Shift the shift lever to P.
Bring the electronic key back
into the vehicle.
Interior
buzzerExteriorbuzzerWarning messageDetails/Actions
(Flashes)
(Flashes)
(Displayed alternately)
(Flashes)
Page 495 of 600
495
7-2. Steps to take in an emergency
7
When trouble arises
GS450h_300h_OM_OM30F92E_(EE)
Con-
tinuous
(Vehicles with the entry function)
An attempt was made to lock the
doors using the smart entry & start
system while the electronic key was still inside the vehicle. Retrieve the electronic key
from the vehicle and lock the
doors again.
OnceCon-
tinuous
An attempt was made to lock either
front door by opening a door and
putting the inside lock button into
the lock position, then closing the
door by pulling on the outside door
handle with the electronic key still
inside the vehicle.
For some models only: An attempt
was made to lock the doors other
than using the smart entry & start
system while the electronic key was
still inside the vehicle. Retrieve the electronic key
from the vehicle and lock the
doors again.
Once
Page 496 of 600

4967-2. Steps to take in an emergency
GS450h_300h_OM_OM30F92E_(EE)
Power was turned off due to the
automatic power off function. Next time when starting the
hybrid system, operate the
hybrid system for approximately
5 minutes to recharge the 12-
volt battery.
OnceThe electronic key has a low battery. Replace the electronic key bat-
tery. ( P. 435)
Once
The driver’s door was opened and
closed with the power switch turned
off and then the power switch was
put in ACCESSORY mode twice
without the hybrid system being
started. Press the power switch while
depressing the brake pedal.
During an hybrid system starting
procedure in the event that the elec-
tronic key was not functioning prop-
erly ( P. 528), the power switch
was touched with the electronic key. Press the power switch within 10
seconds of the buzzer sounding.
Once
The steering lock could not be
released within 3 seconds of the
power switch being pressed. Press the power switch while
depressing the brake pedal and
moving the steering wheel left
and right.
Interior
buzzerExteriorbuzzerWarning messageDetails/Actions
(Flashes)