2015 LEXUS RX450h key battery

6874-3. Do-it-yourself maintenance
4
Maintenance and care Electronic key battery Replace the battery with a new one if it is discharged.
■ You will need the following items:
● Flathead screwdriver
● Small Phillips-head sc rewdriver
● Lithium battery (CR1632)
■ Replacing the battery
Take out the mechanical key.
Remove the cover.
Remove the depleted battery.
Insert a new battery with the “+”
terminal facing up.STEP 1
STEP 2
STEP 3

6884-3. Do-it-yourself maintenance
■
Use a CR1632 lithium battery ●
Batteries can be purchased at your Le xus 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 the local laws.■
If the electronic key battery is discharged
The following symptoms may occur: ●
The smart access system with push-button start and wireless remote control will
not function properly.●
The operational range is reduced.■
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.
CAUTION■
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.
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 arises
5
7235-1. Essential information
Emergency flashers............... 724
If your vehicle needs to be
towed ...................................... 725
If you think something is
wrong ...................................... 732 5-2. Steps to take in an
emergency
If a warning light turns on
or a warning buzzer
sounds... ................................. 733
If a warning message is
displayed................................. 743
If you have a flat tire................ 764
If the hybrid system will
not start ................................... 777
If the shift lever cannot be
shifted from P ........................ 779
If you lose your keys .............. 780
If the electronic key does
not operate properly........... 781
If the vehicle 12-volt
battery is discharged ......... 784
If your vehicle overheats ..... 788
If the vehicle becomes
stuck........................................ 793
If your vehicle has to
be stopped in an
emergency ............................ 795

5
When trouble arises
7615-2. Steps to take in an emergency
Sounds
once 
(Flashes) An attempt was
made to turn the
“POWER” switch
off when the shift
lever was not in P. To turn off the
hybrid system,
first shift the shift
lever to P and
then turn the
“POWER” switch
off.
  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 hybrid system
speed slightly and
maintain that level
for approximately
5 minutes to
recharge the 12-
volt battery.
Sounds
once  The electronic key
has a low battery. Replace the elec-
tronic key battery.
(  P. 6 8 7 )Interior
buzzer Exterior
buzzer Wa r n i n g m e s s a g e Details Correction
procedure

5
When trouble arises
7775-2. 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 7 7 )
One of the following may be the cause of the problem:
● The electronic key may not be functioning properly. (  P. 7 8 2 )
● There may be a malfunction in the immobilizer system. (  P. 1 2 4 )
● There may be a malfunction in the steering lock system.
● 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. 7 7 8 )
■ 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. 7 8 4 )
● The 12-volt battery terminal co nnections may be loose or cor-
roded.
■ The interior lights and headlights do not turn on, or the horn does
not sound.
One of the following may be the cause of the problem:
● One or both of the 12-volt battery terminals may be discon-
nected.
● The 12-volt battery may be discharged. (  P. 7 8 4 )
Contact your Lexus dealer if the problem cannot be repaired, or if
repair procedures are unknown.

5
When trouble arises
7815-2. Steps to take in an emergency
If the electronic key do es not operate properly
Locking and unlocking the side doors and key linked functions
Use the mechanical key (  P. 5 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)If communication between the electron ic key and vehicle is interrupted
(  P. 62) 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 can be opened and
the hybrid system can be started by following the procedure below.

5
When trouble arises
7835-2. Steps to take in an emergency
■
Stopping the hybrid system
Shift the shift lever to P and press the “POWER” switch 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 elec-
tronic key battery be replaced immediately when the battery is depleted.
(  P. 6 8 7 )■
Changing “POWER” switch modes
Within 10 seconds of the buzzer sounding, release the brake pedal and press the
“POWER” switch.
The hybrid system does not start and modes will be changed each time the switch is
pressed. (  P. 1 7 8 )

5
When trouble arises
7855-2. Steps to take in an emergency
■
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 sy stem while the hybrid system is off.●
Turn off any unnecessary electrical compon ents when the vehicle is running at a
low speed for an extended period, such as in heavy traffic.■
When the 12-volt battery is removed or discharged ●
The power back door must be initialized.
(  P. 8 3 7 )●
The hybrid system may not start. (
 P. 6 6 8 )
●
Make sure that the key is not inside th e vehicle when recharging or replacing
the 12-volt battery. The key may be locked in the vehicle if the alarm is activated.
(  P. 1 2 8 ) Start the engine of the second vehicle. Increase the engine
speed slightly and maintain that level for approximately 5 min-
utes to recharge the 12-volt battery of your vehicle.
Open and close any of the doors of your vehicle with the
“POWER” switch off.
Maintain the engine sp eed of the second ve hicle and start the
hybrid system of your vehicle by turning the “POWER” switch
to ON mode.
Make sure the “READY” indicat or comes on. If the indicator
does not come on, contact your Lexus dealer.
Once the hybrid system has st arted, remove the jumper cables
in the exact reverse order from which they were connected.
Once the hybrid system starts, have the vehicle inspected at your
Lexus dealer as soon as possible. STEP 4
STEP 5
STEP 6
STEP 7
STEP 8