2018 Lexus GS450h key battery

GS450h_OM_OM30G62U_(U)
3636-3. Do-it-yourself maintenance
6
Maintenance and care
■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 access system with push-button start may not be
possible immediately after reconnecting the 12-volt battery. If this happens, use the
wireless remote control or the mechan ical key to lock/unlock the doors.
●Start the hybrid system with the power sw itch 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 turn 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 multip le attempts at all methods above, contact your
Lexus dealer.
WARNING
■Chemicals in the 12-volt battery
The 12-volt battery contains poisonous and corrosive sulfuric acid and may produce
hydrogen gas which is flammable and explosive. To reduce the risk of death or serious
injury, take the following precautions while working on or near the 12-volt battery:
●Do not cause sparks by touching the 12-volt battery terminals with tools.
●Do not smoke or light a match near the 12-volt battery.
●Avoid contact with eyes, skin and clothes.
●Never inhale or swallow electrolyte.
●Wear protective safety glasses when working near the 12-volt battery.
●Keep children away from the 12-volt battery.
■Where to safely charge the 12-volt battery
Always charge the 12-volt battery in an open area. Do not charge the 12-volt battery in
a garage or closed room where th ere is insufficient ventilation.
■How to recharge the 12-volt battery
Recharge at a current of 5 A or less and make sure that the recharging period does not
exceed a total of 12 hours.
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GS450h_OM_OM30G62U_(U)
6-3. Do-it-yourself maintenance
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 depleted battery.
Insert a new battery with the “+” termi-
nal facing up.
Replace the battery with a new one if it is depleted.
You will need the following items:
Replacing the battery
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GS450h_OM_OM30G62U_(U)
3836-3. Do-it-yourself maintenance
6
Maintenance and care
■Use a CR2032 lithium battery
●Batteries can be purchased at your Lexus dealer, loca l electrical appliance shops or
camera stores.
●Replace only with the same or equivalent type recommended by the manufacturer.
●Dispose of used batteries according to local laws.
■If the electronic key battery is depleted
The following symptoms may occur:
●The smart access system with push-button start and wireless remote control will not
function properly.
●The operational rang e will be reduced.
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 coul d result in death or serious injury.
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 co mponent inside the remote control.
●Do not bend either of the battery terminals.

395
GS450h_OM_OM30G62U_(U)
7When trouble arises
7-1. Essential information Emergency flashers .................. 396
If your vehicle has to be stopped in an emergency.... 397
7-2. Steps to take in an emergency If your vehicle needs to be towed................................398
If you think something is wrong ................403
If a warning light turns on or a warning buzzer sounds.....404
If a warning message is displayed ................................. 410
If you have a flat tire ....................441
If the hybrid system will not start................................450
If the parking brake cannot be released ................................ 452
If the electronic key does not operate properly ..................... 454
If the 12-volt battery is discharged ............................. 457
If your vehicle overheats .......... 461
If the vehicle becomes stuck ............................................. 466

4387-2. Steps to take in an emergency
GS450h_OM_OM30G62U_(U)
⎯Con-
tinuous
• An attempt was made to lock thedoors using the sm art access sys-
tem with push-button start while
the electronic key was still inside
the vehicle.
• 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 with the elec-
tronic key still inside the vehicle.
→ Retrieve the electronic key
from the vehicle and lock the
doors again.
Once⎯
• When the doors were unlocked
with the mechanical key and then
the power switch was pressed, the
electronic key could not be
detected in the vehicle.
• The electronic key could not be
detected in the vehicle even after
the power switch was pressed two
consecutive times.
→ Touch the electronic key to the
power switch while depressing
the brake pedal.
Once⎯
An attempt was made to start the
hybrid system with the shift lever in
an incorrect position.
→ Shift the shift lever to P and start
the hybrid system.
⎯⎯
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.
Interior
buzzerExteriorbuzzerWarning messageDetails/Actions
(Flashes)

4397-2. Steps to take in an emergency
GS450h_OM_OM30G62U_(U)
7
When trouble arises
Once⎯
The electronic key has a low battery.
→Replace the electronic key bat-
tery. ( →P. 382)
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. 455), 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.
Once⎯
The power switch has been turned
off with the shift lever in a position
other than P or N.
→Shift the shift lever to P.
Interior
buzzerExteriorbuzzerWarning messageDetails/Actions
(Flashes)
(Flashes)

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GS450h_OM_OM30G62U_(U)
7-2. Steps to take in an emergency
If the hybrid system will not start
One of the following may be the cause of the problem:
●The electronic key may not be functioning properly. (→P. 455)
●There may not be sufficient fuel in the vehicle’s tank.
Refuel the vehicle.
●There may be a malfunction in the immobilizer system. ( →P. 74)
●There may be a malfunction in the steering lock system.
●The hybrid system may be malfunctioni ng due to an electrical problem such
as electronic key battery depletion or a blown fuse. However, depending on
the type of malfunction, an interim meas ure is available to start the hybrid sys-
tem. ( →P. 451)
One of the following may be the cause of the problem:
●The 12-volt battery may be discharged. ( →P. 457)
●The 12-volt battery terminal connections may be loose or corroded.
(→ P. 362)
One of the following may be the cause of the problem:
●The 12-volt battery may be discharged. ( →P. 457)
●One or both of the 12-volt battery terminals may be disconnected. ( →P. 362)
Contact your Lexus dealer if the problem cannot be repaired, or if repair procedures
are unknown.
Reasons for the hybrid system not star ting vary depending on the situation.
Check the following and perform the appropriate procedure:
The hybrid system will not start even though the correct starting proce-
dure is being followed. ( →P. 182)
The interior lights and headlights are d im, or the horn does not sound or
sounds at a low volume.
The interior lights and headlights do not turn on, or the horn does not
sound.

454
GS450h_OM_OM30G62U_(U)
7-2. Steps to take in an emergency
If the electronic key does not operate properly
■Doors
Use the mechanical key (→P. 119) in
order to perform the following oper-
ations:
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 within 5 seconds unlocks the
other doors.
Opens the windows and moon roof* (turn and hold)
*: This setting must be custom ized at your Lexus dealer.
■Trunk
Turn the mechanical key clockwise
to open.
If communication between the electronic key and vehicle is interrupted
(→ P. 137) or the electronic key ca nnot be used because the battery is
depleted, the smart access system with push-button start and wireless
remote control cannot be used. In su ch cases, the doors 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
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