2022 LEXUS RX450h key battery

3876-3. Do-it-yourself maintenance
6
Maintenance and care
of the flathead screwdriver with a tape.
3Remove the depleted battery.
When removing the cover, the electronic
key module may stick to the cover and the
battery may not be visible. In this case,
remove the electronic key module in order
to remove the battery.
Insert a new battery with the “+” terminal
facing up.
WARNING
■Battery precautions
Observe the following precautions.
Failure to do so may result in death or
serious injury.
●Do not swallow the battery. Doing so
may cause chemical burns.
●A coin battery or button battery is
used in the electronic key. If a battery is
swallowed, it may cause severe chemi-
cal burns in as little as 2 hours and may
result in death or serious injury.
●Keep away new and removed batteries
from children.
●If the cover cannot be firmly closed,
stop using the electronic key and stow
the key in the place where children
cannot reach, and then contact your
Lexus dealer.
●If you accidentally swallow a battery or
put a battery into a part of your body,
get emergency medical attention
immediately.
■To prevent battery explosion or leak-
age of flammable liquid or gas
●Replace the battery with a new battery
of the same type. If a wrong type of
battery is used, it may explode.
●Do not expose batteries to extremely
low pressure due to high altitude or
extremely high temperatures.
●Do not burn, break or cut a battery.
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 com-
ponent inside the remote control.
●Do not bend either of the battery ter-
minals.

401
7
7
When trouble arises
When trouble arises
.7-1. Essential informationEmergency flashers.................. 402
If your vehicle has to be stopped in an emergency .......................... 402
If the vehicle is submerged or water on the road is rising
........................................................ 403
7-2. Steps to take in an emergency If your vehicle needs to be towed........................................................ 405
If you think something is wrong ........................................................ 409
If a warning light turns on or a warning buzzer sounds ........ 410
If a warning message is displayed ........................................................ 420
If you have a flat tire.................. 424
If the hybrid syst em will not start
........................................................ 436
If you lose your keys ................. 438
If the fuel filler door cannot be opened........................................ 438
If the electronic key does not operate properly .................... 439
If the 12-volt battery is discharged ......................................................... 441
If your vehicle overheats ........ 446
If the vehicle becomes stuck ........................................................ 449

4237-2. Steps to take in an emergency
7
When trouble arises
nance is performed. (P.356)
*: Refer to the separate “Scheduled Main-
tenance” or “Owner’s Manual Supple-
ment” for the maintenance interval
applicable to your vehicle.
■If “Maintenance Required Visit Your
Dealer” is displayed (U.S.A. only)
Indicates that all maintenance is required to
correspond to the driven distance on the
maintenance schedule
*.
Comes on approximately 5000 miles
(8000 km) after the message has been
reset. (The indicator will not work properly
unless the message ha s been reset.) Per-
form the necessary maintenance. Please
reset the message after the maintenance is
performed. ( P.356)
*: Refer to the separate “Scheduled Main-
tenance” or “Owner’s Manual Supple-
ment” for the maintenance interval
applicable to your vehicle.
■If “Oil Maintenance Required Soon” is
displayed
Indicates that the en gine oil should be
scheduled to be changed.
Check the engine oil and change it if neces-
sary. After changing the engine oil, make
sure to reset the message. ( P.367)
■If “Oil Maintenance Required” is dis-
played
Indicates that the en gine oil should be
changed.
Check and change the engine oil, and oil fil-
ter by your Lexus deal er. After changing the
engine oil, make sure to reset the message.
(  P.367)
■If a message that in dicates the need for
visiting your Lexus dealer is displayed
The system or part shown on the
multi-information display is malfunctioning.
Have the vehicle inspected by your Lexus
dealer immediately.
■If a message that in dicates the need for
referring to Owner’s Manual is dis-
played
●“Engine Coolant Temp High” is shown on the multi-information display, follow the
instructions. (
P.446)
●If any of the following messages are
shown on the multi-info rmation display, it
may indicate a malf unction. Have the
vehicle inspected by your Lexus dealer
immediately.
• “Access System with Elec. Key Malfunc-
tion”
• “Hybrid System Malfunction”
•“Check Engine”
• “Hybrid Battery System Malfunction”
• “Accelerator System Malfunction”
●If any of the following messages are
shown on the multi-info rmation display, it
may indicate a malfun ction. Immediately
stop the vehicle and contact your Lexus
dealer.
• “Braking Power Low”
• “Charging Syst em Malfunction”
• “Oil Pressure Low”
NOTICE
■If “High Power Consumption Partial
Limit On AC/Heater Operation” is
displayed frequently
There is a possible malfunction relating
to the charging system or the 12-volt bat-
tery may be deteriorating. Have the vehi-
cle inspected by your Lexus dealer.

4367-2. Steps to take in an emergency
One of the following may be the cause
of the problem:
The electronic key may not be func-
tioning properly. ( P.439)
 There may not be sufficient fuel in
the vehicle’s tank.
Refuel the vehicle.
 There may be a malfunction in the
immobilizer system. ( P.73)
 There may be a malfunction in the
steering lock system.
 The hybrid system may be malfunc-
tioning due to an electrical problem
such as electronic key battery
depletion or a blown fuse. However,
depending on the type of malfunc-
tion, an interim measure is available
to start the hybrid system. ( P.437)
One of the following may be the cause
NOTICE
■Proper storage of the spare tire
(RX450hL)
●If the hoist assembly is slanted when
stowing a tire, the hoist assembly may
become stuck in the wheel opening
and the tire may not be raised properly,
causing damage to the wheel or the
wire cable.
●If the spare tire clamp bolt is turned
without a tire on the hoist assembly, the
wire cable may not be able to be low-
ered. If the wire cable cannot be low-
ered, contact your Lexus dealer.
If the hybrid system will not
start
Reasons for the hybrid system not
starting vary depending on the situ-
ation. Check the following and per-
form the appropriate procedure:
The hybrid system will not start
even though the correct starting
procedure is being followed.
(  P.182)
The interior lights and head-
lights are dim, or the horn does
not sound or sounds at a low vol-
ume.

4397-2. Steps to take in an emergency
7
When trouble arises
fuel tank. Therefore, fill the fuel tank
carefully and slowly.
RX450hL
 If the fuel filler door opener switch
cannot be operated, contact your
Lexus dealer to service the vehicle.
In case where refueling is urgently
necessary, remove the cover inside
the luggage compartment using a
tool, such as a flathead screwdriver,
and pull the lever to open the fuel
filler door.
When using a screwdri ver, make sure to
wrap its tip with tape to protect the cover.
 Using the lever to open the fuel filler
door may not allow for an adequate
reduction in fuel tank pressure
before refueling. To prevent fuel
from spilling out, turn the cap slowly
when removing it.
During refueling, fuel may spill out
from the filler opening due to air
being discharged from inside the
fuel tank. Therefore, fill the fuel tank
carefully and slowly.
■When the electronic key does not work
properly
●Make sure that the smart access system
with push-button star t has not been dis-
abled at your Lexus dealer. If it has been
disabled, re-enable it.
●Check if battery-saving mo de is set. If it is
set, cancel the function. ( P.126)
■Unlocking the door
Use the mechanical key ( P.107) in
order to perform the following opera-
tions:
If the electronic key does not
operate properly
If communication between the
electronic key and vehicle is inter-
rupted ( P.126) 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.
NOTICE
■In case of a smart access system with
push-button start malfunction or
other key-rela ted problems
Take your vehicle with all the electronic
keys provided with your vehicle to your
Lexus dealer.
Locking and unlocking the doors

4417-2. Steps to take in an emergency
7
When trouble arises
When the smart access system with
push-button start is deactivated in
customization setting, the power switch will
turn to ACCESSORY mode.
3Firmly depress the brake pedal and
check that is shown on the
multi-information display.
4 Press the power switch shortly and
firmly.
In the event that the hybrid system still
cannot be started, contact your Lexus
dealer.
■Stopping the hybrid system
Shift the shift lever to P, set the parking
brake, and press the power switch as you
normally do when stopping the hybrid sys-
tem.
■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.386)
■Alarm (For Canada)
Using the mechanical key to lock the doors
will not set the alarm system.
If a door is unlocked using the mechanical
key when the alarm system is set, the alarm
may be triggered. ( P.74)
■Changing power switch modes
Release the brake pedal and press the
power switch in step 3 above. The hybrid
system does not start and modes will be
changed each time the switch is pressed.
(  P.185)
If the 12-volt battery is dis-
charged
The following procedures may be
used to start the hybrid system if the
vehicle’s 12-volt battery is dis-
charged.
You can also call your Lexus dealer
or a qualified repair shop.

4427-2. Steps to take in an emergency
If you have a set of jumper (or booster)
cables and a second vehicle with a
12-volt battery, you can jump start your
vehicle by following the steps below.
1Confirm that the electronic key is
being carried.
When connecting the jumper (or booster)
cables, depending on the situation, the
alarm may activate and doors locked.
( P.75)
2 Open the hood ( P.363) and fuse
box cover. 3
Open the exclusive jump starting
terminal cover.
4 Remove the engine cover.
5 Connect a positive jumper cable clamp to on your vehicle and connect the
clamp on the other end of the positive cab le to on the second vehicle. Then,
Restarting the hybrid system
A
B

4447-2. Steps to take in an emergency
ponents when the vehicle is running at a
low speed for an extended period, such
as in heavy traffic.
■When removing the 12-volt battery ter-
minals
When the 12-volt battery terminals are
removed, the information stored in the
ECU is cleared. Before removing the
12-volt battery terminals, contact your
Lexus dealer.
■Charging the 12-volt battery
The electricity stored in the 12-volt battery
will discharge gradually even when the
vehicle is not in use, due to natural dis-
charge and the draining effects of certain
electrical appliances. If the vehicle is left for
a long time, the 12-volt battery may dis-
charge, and the hybrid system may be
unable to start. (T he 12-volt battery
recharges automatically while the hybrid
system is operating.)
■When the 12-volt battery is removed or
discharged
●In some cases, it may not be possible to
unlock the doors using the smart access
system with push-button start when the
12-volt battery is discharged. Use the
wireless remote control or the mechani-
cal key to lock or unlock the doors.
●The hybrid system may not start on the
first attempt after the 12-volt battery has
recharged but will start normally after the
second attempt. This is not a malfunction.
●The power switch mode is memorized by
the vehicle. When the 12-volt battery is
reconnected, the system will return to the
mode it was in before the 12-volt battery
was discharged. Before disconnecting
the 12-volt battery, turn the power switch
off.
If you are unsure what mode the power
switch was in before the 12-volt battery
discharged, be especially careful when
reconnecting the 12-volt battery.
●The power back door mu st be initialized.
( P.119)
■When replacing the 12-volt battery
●RX450h: Use a Central Degassing type
12-volt battery (European Regulations). RX450hL: Use a 12-volt battery
designed for this vehicle.
●RX450h: Use a 12-volt battery that the
case size is same as the previous one
(LN2), 20 hour rate capacity (20HR) is
equivalent (60Ah) or greater, and per-
formance rating (CCA) is equivalent
(460A) or greater.
• If the sizes differ, the 12-volt battery can- not be properly secured.
• If the 20 hour rate capacity is low, even if
the time period where the vehicle is not
used is a short time, the 12-volt battery
may discharge and the hybrid system
may not be able to start.
●Use a 12-volt battery with a handle. If a
12-volt battery without a handle is used,
removal is more difficult.
●After replacing, firm ly attach the follow-
ing items to the exhaust hole of the
12-volt battery.
• Use the exhaust hose that was attached to the 12-volt battery before replacing
and confirm that it is firmly connected to
the hole section of the vehicle.
• Use the exhaust hole plug included with the 12-volt battery re placed or the one
installed on the 12-volt battery prior to
the replacement. (Depending on the
12-volt battery to be replaced, the
exhaust hole may be plugged.)
RX450h
Exhaust hole plug
Exhaust hole
A
B