2011 Lexus HS250h key battery

440
4-3. Do-it-yourself maintenance
■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 discon-
nect the ground cable.
●Make sure the power switch on the charger is off when connecting and discon-
necting the charger cables to the 12-volt battery.
■After recharging/reconnecting the 12-volt battery
●Unlocking the doors using the smart key system may not be possible immedi-
ately after reconnecting the 12-volt batt ery. 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 system 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 battery is recon-
nected, the vehicle will return the “POWER” switch mode to the status it was in
before the battery was disconnected. Make sure to turn off the power before
disconnect the battery. Take extra care when connecting the battery if the
“POWER” switch mode prior to discharge is unknown.
■ Exterior
Make sure that the 12-volt ba ttery terminals are not corroded and
that there are no loose connect ions, cracks or loose clamps.
Terminals
Hold-down clamp

459
4-3. Do-it-yourself maintenance
4
Maintenance and care
Electronic key battery
Replace the battery with a new one if it is depleted.
■You will need the following items:
●Flathead screwdriver
● Small flathead screwdriver
● Lithium battery (CR1632)
■ Replacing the battery
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 “+”
terminal facing up.

460
4-3. Do-it-yourself maintenance
■Use a CR1632 lithium battery
●Batteries can be purchased at your Lexus dealer, local electrical appliance
shops or camera stores.
●Replace only with the same or equivalent type recommended by the manufac-
turer.
●Dispose of used batteries according to 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 access system with push-button start and wireless remote control will
not function properly.
●The operational range will be reduced.
CAUTION
■Removed battery and other parts
Keep away from children. These parts are small and if swallowed by a child, they can
cause choking. 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 comp onents inside the remote control.
●Do not bend either of the battery terminals.

When trouble arises5
487
5-1. Essential informationEmergency flashers .............. 488
If your vehicle needs to be towed ................................ 489
If you think something is wrong ...................................... 495
Event data recorder.............. 496
5-2. Steps to take in an emergency
If a warning light turns on or a warning buzzer
sounds... ................................. 498
If a warning message is displayed................................ 507
If you have a flat tire............... 527
If the hybrid system will not start ......................................... 537
If you lose your keys .............. 539
If the electronic key does not operate properly.......... 540
If the vehicle 12-volt battery is discharged......................... 543
If your vehicle overheats ..... 548
If the vehicle becomes stuck........................................ 552
If your vehicle has to be stopped in
an emergency ...................... 554

524
5-2. Steps to take in an emergency

Po w e r w a s t u r n e d
off due to the
automatic power
off function.
Next time when
starting the hybrid
system, increase
the engine speed
slightly and main-
tain that level for
approximately 5
minutes to
recharge the 12-
volt battery.
OnceThe electronic key
has a low battery.Replace the elec-
tronic key battery.
(P. 4 5 9 )
Interior
buzzerExterior buzzerWa r n i n g m e s s a g eDetailsCorrection
procedure

5
When trouble arises
537
5-2. Steps to take in an emergency
If the hybrid system will not start
Reasons for the hybrid system not starting vary depending on the situation.
Check the following and perform the appropriate procedure:
■The hybrid system will not start even though the correct starting
procedure is being followed. ( P. 1 4 7 )
One of the following may be the cause of the problem:
● The electronic key may not be functioning properly.* (P. 540)
● There may not be sufficient fuel in the vehicle’s tank.
Refuel the vehicle.
● There may be a malfunction in the immobilizer system.* (P. 9 8 )
● There may be a malfunction in the P position control system.*
( P. 150, 508)
● The hybrid system may be malfunc tioning due to an electrical
problem such as an open circ uit or a blown fuse. However,
depending on the type of malfunc tion, an interim measure is avail-
able to start the hybrid system. ( P. 4 6 1 )
*: It may not be possible to shift out of the P position.
■The interior lights and headlights are dim, or the horn does not
sound or sounds at a low volume.
One of the following may be the cause of the problem:
● The 12-volt battery may be discharged. ( P. 543)
● The 12-volt battery terminal co nnections may be loose or cor-
roded.

540
5-2. Steps to take in an emergency
If the electronic key does not operate properly
Locking and unlocking the doors, unlocking the trunk and key linked functions
Doors
Use the mechanical key (P. 4 0 )
in order to perform the following
operations (driver’s door only):
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 unlocks the other
doors.
Opens the windows and moon
roof (turn and hold)
*
*: This setting must be customized at your Lexus dealer.
If communication between the electron ic key and vehicle is interrupted
(  P. 50) or the electronic key cannot 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.

542
5-2. Steps to take in an emergency
To change “POWER” switch modes: Within 10 seconds of the
buzzer sounding, release the brake pedal and press the
“POWER” switch. Modes can be changed each time the switch is
pressed. ( P. 1 4 8 )
To start the hybrid system: Press the “POWER” switch within 10
seconds of the buzzer sound ing, keeping the brake pedal
depressed.
In the event that the hybrid system still cannot be operated, contact your
Lexus dealer.
■Stopping the hybrid system
In the same method as the normal hybrid system stopping procedure, completely
stop the vehicle and then press the “POWER” switch.
■Replacing the key battery
As the above procedure is a temporary measure, it is recommended that the elec-
tronic key battery be replaced immediately when the battery is depleted.
(  P. 4 5 9 )
■When the electronic key does not work properly
Make sure that the smart access system wi th push-button start has not been deacti-
vated in the customization setting. If it is off, turn the function on.
(Customizable features P. 5 8 0 )