2012 Lexus HS250h key battery

Maintenance and care4
415
HS250h_U_75050U
4-1. Maintenance and careCleaning and protecting the vehicle exterior.............. 416
Cleaning and protecting the vehicle interior .............. 420
4-2. Maintenance Maintenance requirements ........................ 423
General maintenance .......... 426
Emission inspection and maintenance (I/M)
programs............................... 430 4-3. Do-it-yourself maintenance
Do-it-yourself service precautions ............................ 431
Hood .......................................... 434
Positioning a floor jack ......... 435
Engine compartment ........... 437
12-volt battery ........................ 447
Tires............................................. 451
Tire inflation pressure........... 459
Wheels ...................................... 462
Air conditioning filter ........... 464
Electronic key battery........... 467
Checking and replacing fuses ........................................ 469
Light bulbs................................. 481

448
4-3. Do-it-yourself maintenance
HS250h_U_75050U
■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 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 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 battery terminals are not corroded and
that there are no loose connections, cracks or loose clamps.
Te r m i n a l s
Hold-down clamp

467
4-3. Do-it-yourself maintenance
4
Maintenance and care
HS250h_U_75050U
Electronic key battery
Replace the battery with a new one if it is depleted.
■You will need th e 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.

468
4-3. Do-it-yourself maintenance
HS250h_U_75050U
■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 could 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 components inside the remote control.
●Do not bend either of the battery terminals.

When trouble arises5
493
HS250h_U_75050U
5-1. Essential informationEmergency flashers .............. 494
If your vehicle needs to be towed ................................ 495
If you think something is wrong ....................................... 501
5-2. Steps to take in an emergency
If a warning light turns on or a warning buzzer
sounds... ................................. 502
If a warning message is displayed................................. 512
If you have a flat tire............... 532
If the hybrid system will not start .......................................... 541
If you lose your keys .............. 543
If the electronic key does not operate properly.......... 544
If the vehicle 12-volt battery is discharged ......... 547
If your vehicle overheats ..... 552
If the vehicle becomes stuck........................................ 556
If your vehicle has to be stopped in
an emergency ...................... 558

5
When trouble arises
529
5-2. Steps to take in an emergency
HS250h_U_75050U

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 6 7 )
Interior
buzzerExterior buzzerWa r n i n g m e s s a g eDetailsCorrection
procedure

5
When trouble arises
541
5-2. Steps to take in an emergency
HS250h_U_75050U
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 star t even though the correct starting
procedure is being followed. ( →P. 152)
One of the following may be the cause of the problem:
● The electronic key may not be functioning properly.* ( →P. 544)
● There may not be sufficient fuel in the vehicle’s tank.
Refuel the vehicle.
● There may be a malfunction in the immobilizer system.* ( →P. 1 0 1 )
● There may be a malfunction in the P position control system.*
(→ P. 155, 513)
● The hybrid system may be malfunctioning due to an electrical
problem such as an open circuit or a blown fuse. However,
depending on the type of malfunction, an interim measure is avail-
able to start the hybrid system. ( →P. 4 6 9 )
*: 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. 547)
● The 12-volt battery terminal connections may be loose or cor-
roded.

544
5-2. Steps to take in an emergency
HS250h_U_75050U
If the electronic key does not operate properly
Locking and unlocking the doors, unlocking the trunk and key linked functions
DoorsUse the mechanical key (→P. 4 2 )
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 electronic key and vehicle is interrupted
(→ P. 52) 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 such cases, the doors and trunk can be
opened and the hybrid system can be started by following the procedure
below.