2019 LEXUS RX350 key battery

6017-3. Do-it-yourself maintenance
7
Maintenance and care
RX350/RX350L_U Check the battery as follows. ■
Battery exterior Make sure that the battery terminals are not corroded and that there are no
loose connections, cracks, or loose clamps.
Terminals
Hold-down clamp ■
Before recharging
When recharging, the battery produces hydrogen gas which is flammable and explosive.
Therefore, observe the following precautions before recharging: ●
If recharging with the battery installed on the vehicle, be sure to disconnect the ground
cable. ●
Make sure the power switch on the charge r is off when connecting and disconnecting
the charger cables to the battery. ■
After recharging/reconnecting the battery ●
The engine may not start. Follow the pr ocedure below to in itialize the system.
Shift the shift lever to P.
Open and close any of the doors.
Restart the engine.●
Unlocking the doors using the smart access system with push-button start may not be
possible immediately after reconnecting the battery. If this happens, use the wireless
remote control or the mechanical key to lock/unlock the doors.●
Start the engine with the engine switch in ACCESSORY mode. The engine may not
start with the engine switch turned off. However, the engine will operate normally from
the second attempt. ●
The engine switch mode is recorded by the vehicle. If the battery is reconnected, the
vehicle will return the engine 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 engine 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.Battery 1
2
1
2
3

6237-3. Do-it-yourself maintenance
7
Maintenance and care
RX350/RX350L_U ●
Flathead screwdriver ●
Lithium battery CR2032
Take out the mechanical key.
Remove the cover. To prevent damage to the key, cover the
tip of the flathead screwdriver with a
tape.
Remove the depleted battery. When removing the cover, the elec-
tronic key module may stick to the cover
and the battery may not be visible. In this
case, remove the el ectronic key module
in order to remove the battery.
Insert a new battery with the “+” termi-
nal facing up.Electronic key battery Replace the battery with a new one if it is depleted.
You will need the following items:
Replacing the battery 1
2
3

624 7-3. Do-it-yourself maintenance
RX350/RX350L_U ■
Use a CR2032 lithium battery ●
Batteries can be purc hased 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 the 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.

643
8When trouble arises
RX350/RX350L_U 8-1. Essential information
Emergency flashers .................. 644
If your vehicle has
to be stopped in
an emergency .......................... 645
8-2. Steps to take in
an emergency
If your vehicle needs
to be towed................................ 646
If you think something is
wrong ........................................... 652
Fuel pump shut off
system .......................................... 653
If a warning light turns on
or a warning buzzer
sounds.......................................... 654
If a warning message is
displayed...................................... 661
If you have a flat tire .................. 666
If the engine will not start ........ 682
If the electronic key does
not operate properly .............684
If the vehicle battery is
discharged ................................. 687
If your vehicle overheats ......... 692
If the vehicle becomes
stuck ............................................. 695

6638-2. Steps to take in an emergency
8
When trouble arises
RX350/RX350L_U Take the appropriate actions as in structed in the message displayed.
If any of the following messages are displa yed, also refer to this Owner’s Manual.■
If “Shift to P Before Exiting Vehicle” is shown
Message is displayed when the driver’s door is opened without turning the
engine switch off with the shift le ver in any position other than P.
Shift the shift lever to P. ■
If “Power Turned Off to Save Battery” is displayed
This message is displayed when the power was cut off due to the automatic
power off function.
The next time the engine is started, increase the engine speed slightly and
maintain it at that speed for approxim ately 5 minutes to recharge the battery.■
If “AWD System Overheated Switching to 2WD Mode” or “AWD System
Overheated 2WD Mode Engaged” is displayed (AWD models)
This message may be displayed when driving under extremely high load con-
ditions.
Drive the vehicle at low speeds or stop the vehicle in a safe place with the
engine running until the message is cleared.
If the message is not cleared, have the vehicle inspected by your Lexus dealer. ■
If “A New Key has been Registered Contact Your Dealer for Details” is dis-
played
This message will be displayed each time the driver’s door is opened when the
doors are unlocked from the outside fo r approximately one week after a new
electronic key has been registered.
If this message is displayed but you ha ve not had a new electronic key regis-
tered, ask your Lexus dealer to check if an unknown electronic key (other than
those in your possession) has been registered. ■
When “Headlight System Malfunctio n Visit Your Dealer” is displayed
The following systems may be malfunct ioning. Have the vehicle inspected by
your Lexus dealer immediately. ●
The LED headlight system ●
The automatic headlight leveling system ●
Automatic High Beam ●
AFS (Adaptive Front-lighting System) (if equipped)Other messages displayed on the multi-information display

682 8-2. Steps to take in an emergency
RX350/RX350L_U One of the following may be the cause of the problem: ●
There may not be sufficient fuel in the vehicle’s tank.
Refuel the vehicle. ●
The engine may be flooded.
Try to restart the engine again follo wing correct starting procedures.
(  P. 231)●
There may be a malfunction in th e engine immobilizer system. (  P. 74)
One of the following may be the cause of the problem: ●
The battery terminal connections may be loose or corroded. ●
The battery may be discharged. (  P. 687)
The engine starting system may be malfun ctioning due to an electrical problem
such as electronic key battery depletio n or a blown fuse. However, an interim
measure is available to start the engine. (  P. 683)If the engine will not start If the engine will not start even though correct starting procedures are being
followed (  P. 231), consider each of the following points:
The engine will not start even thoug h the starter motor operates nor-
mally.
The starter motor turns over slowly , the interior lights and headlights
are dim, or the horn does not sound or sounds at a low volume.
The starter motor does not turn over

684 8-2. Steps to take in an emergency
RX350/RX350L_U ■
Unlocking the door
Use the mechanical key (  P. 121) in order to pe rform the following opera-
tions:
Insert the mechanical key while
pulling on the driver’s door han-
dle.
Unlocking the door. Turning the key rearward unlocks the
driver’s door. Turning the key again
unlocks the other doors.
Remove the key, return the handle, and then pull the handle again.If the electronic key does not operate properly If communication between the electronic key and vehicle is interrupted
(  P. 148) or the electronic key ca nnot be used because the battery is
depleted, the smart access system wi th push-button start and wireless
remote control cannot be used. In such cases, the doors can be opened and
the engine can be started by following the procedure below.
Locking and unlocking the doors 1
2
3

686 8-2. Steps to take in an emergency
RX350/RX350L_U ■
Stopping the engine
Shift the shift lever to P, set the parking br ake, and press the engine switch as you nor-
mally do when stop ping the engine.■
Replacing the key battery
As the above procedure is a temporary measure, it is recommended that the electronic
key battery be replaced immediately when the battery is depleted. (  P. 623)■
Changing engine switch modes
Release the brake pedal and press the engine switch in step above.
The engine does not start and modes will be changed each time the switch is pressed.
(  P. 232) ■
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. 722)●
Check if battery-saving mode is set. If it is set, cancel the function. (  P. 148)
WARNING ■
When using the mechanical key and operating the power windows or the moon roof
or panoramic moon roof
Operate the power window or the moon roof or panoramic moon roof after checking
to make sure that there is no possibility of any passenger having an y of their body parts
caught in the window or the moon roof or panoramic moon roof.
Also, do not allow children to op erate the mechanical key. It is possible for children and
other passengers to get caught in the powe r window or the moon roof or panoramic
moon roof. 3