2023 TOYOTA BZ4X key battery

4977-3. Do-it-yourself maintenance
Owners Manual_USA_M42C01_en
7
Maintenance and care
■If the key battery is depleted
The following symptoms may occur:
●The smart key system and wire-
less remote contr ol will not func-
tion properly.
●The operational range will be
reduced.
Prepare the following before
replacing the battery:
 Flathead screwdriver
 Small flathead screwdriver
 Lithium battery CR2450
■Use a CR2450 lithium battery
●Batteries can be purchased at
your Toyota dealer, local electrical
appliance shops or camera stores.
●Replace only with the same or
equivalent type recommended by
the manufacturer.
●Dispose of used ba tteries accord-
ing to the local laws.
1 Release the lock and remove
the mechanical key.
2 Remove the key cover.
Use a screwdriver of an appropriate
size. Forcedly prying may cause
the cover damaged.
To prevent damage to the key,
cover the tip of the flathead screw-
driver with a rag.
3Remove the depleted battery
using a small flathead screw-
driver.
When removing the cover, the elec-
tronic key module may stick to the
cover and the batt ery may not be
visible.
In this case, remove the electronic
key module in order to remove the
battery.
When removing the battery, use a
screwdriver of an appropriate size.
Insert a new battery with the “+” ter-
Electronic key batter y
Replace the battery with a
new one if it is depleted.
Items to prepare
Replacing the battery

4987-3. Do-it-yourself maintenance
Owners Manual_USA_M42C01_enminal facing up.
4
When installing the key cover
and mechanical key, install
by conducting step 2 and
step 1 with the directions
reversed.
WARNING
■Battery precautions
Observe the following precau-
tions.
Failure to do so m ay result in
death or serious injury.
●Do not swallow the battery.
Doing so may cause chemical
burns.
●A coin battery o r button battery
is used in the electronic key. If a
battery is swallowed, it may
cause severe chemical 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
Toyota dealer.
●If you accidentally swallow a
battery or put a battery into a
part of your b ody, get emer-
gency medical attention imme-
diately.
■To prevent battery explosion
or leakage of flammable liq-
uid 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 pr essure due to
high altitude or extremely high
temperatures.
●Do not burn, bre ak or cut a bat-
tery.
NOTICE
■When replacing the battery
Use a flathead screwdriver of
appropriate size. Applying exces-
sive force may deform or damage
the cover.
■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
component inside the remote
control.
●Do not bend either of the battery
terminals.

503
Owners Manual_USA_M42C01_en
8
8
When trouble arises
When trouble arises
8-1. Essential informationEmergency flashers .... 504
If your vehicle has to be stopped in an emergency.................................. 505
If the vehicle is submerged or water on the road is ris-
ing ............................. 506
8-2. Steps to take in an emer- gency
If your vehicle needs to be towed......................... 507
If you think something is wrong ........................ 511
If a warning light turns on or a warning buzzer sounds
.................................. 513
If a warning message is dis- played........................ 522
If you have a flat tire.... 527
If the EV syst em will not
start ........................... 537
If you lose your keys ... 539
If the electronic key does not operate properly .. 539
If the 12-volt battery is dis- charged ..................... 541
If your vehicle overheats .................................. 545
If the vehicle becomes stuck .................................. 547

5078-2. Steps to take in an emergency
Owners Manual_USA_M42C01_en
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When trouble arises
8-2.Steps to take in an emergency
In the following situations, it is
not possible to be towed by
another vehicle using cables or
chains, as the front wheels may
be locked due to the parking
lock. Contact your Toyota dealer
or commercial towing service.
 There is a malfunction in the
shift control system. ( P.233,
525)
 There is a malfunction in the
immobilizer system. ( P. 6 8 )
 There is a malfunction in the
smart key system. ( P.539)
 The 12-volt battery is dis-
charged. ( P.541) The following may indicate a
problem with your transmission.
Contact your Toyota dealer or
commercial towing service
before towing.

The EV system warning mes-
sage is shown on the multi-
information display and the
vehicle does not move.
 The vehicle makes an abnor-
mal sound.From the front (2WD models)
Release the parking brake.
Turn automatic mode off.
( P.244)
If your vehicle needs
to be towed
If towing is necessary, we
recommend having your
vehicle towed by your Toy-
ota dealer or commercial
towing service, using a
wheel-lift type truck or flat-
bed truck.
Use a safety chain system
for all towing, and abide by
all state/provincial and local
laws.
Situations when it is not
possible to be towed by
another vehicle
Situations when it is nec-
essary to contact dealers
before towing
Towing with a wheel-lift
type truck

5378-2. Steps to take in an emergency
Owners Manual_USA_M42C01_en
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When trouble arises
One of the following may be the
cause of the problem:
 The charging cable may be
connected to the vehicle.
( P.102)
 The electronic key may not be
functioning properly.
*
( P.539)
 The traction battery may be
completely discharged.
Charge the traction battery.
( P.98)
 There may be a malfunction
in the immobilizer system.
*
( P.68)
 There may be a malfunction
in the shift control system.
*
( P.233, 525)
 The EV system may be mal-
functioning due to an electri-
cal problem such as
electronic key battery deple-
tion or a blown fuse. However,
NOTICE
●Do not put the repair kit directly
onto dusty ground such as sand
at the side of the road. If the
repair kit vacuums up dust, etc.,
a malfunction may occur.
●Make sure the sealant bottle of
the repair kit is in a vertical posi-
tion. The repair kit does not
operate properly when it is laid.
■Precautions for the emer-
gency tire puncture repair kit
●The repair kit power source
should be 12 V DC suitable for
vehicle use. Do not connect the
repair kit to any other source.
●Place the repair kit in a storage
to prevent it from being exposed
to dirt or water.
●Store the repair kit in the lug-
gage compartment out of reach
of children.
●Do not disassemble or modify
the repair kit. Do not subject
parts such as the air pressure
indicator to impacts. This may
cause a malfunction.
■To avoid damage to the tire
pressure warning valves and
transmitters
When a tire is repaired with liquid
sealants, the tire pressure warn-
ing valve and transmitter may not
operate properly. If a liquid seal-
ant is used, contact your Toyota
dealer or other qualified service
shop as soon as possible. After
use of liquid sealant, make sure to
replace the tire pressure warning
valve and transmitter when repair-
ing or replacing the tire. ( P.476)
If the EV system will
not star t
Reasons for the EV system
not starting vary depending
on the situation. Check the
following and perform the
appropriate procedure:
The EV system will not
start even though the cor-
rect starting procedure is
being followed ( P.231)

5398-2. Steps to take in an emergency
Owners Manual_USA_M42C01_en
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When trouble arises
■When the electronic key does
not work properly
●Make sure that the smart key sys-
tem has not been deactivated in
the customization setting. If it is
off, turn the function on.
(Customizable features: P.569)
●Check if battery-saving mode is
set. If it is set, cancel the function.
( P.188)
Use the mechanical key
( P.164) in order to perform the
following operations.
If you lose your keys
New genuine keys can be
made by your Toyota dealer
using the other key and the
key number stamped on
your key number plate.
Keep the plate in a safe
place such as your wallet,
not in the vehicle.
NOTICE
■When an electronic key is lost
If the electronic key remains lost,
the risk of vehicle theft increases
significantly. Visit your Toyota
dealer immediately with all
remaining electronic keys that
were provided wit h your vehicle.
If the electronic key
does not operate prop-
erly
If communication between
the electronic key and vehi-
cle is interrupted ( P.188)
or the electronic key cannot
be used because the battery
is depleted, the smart key
system and wireless remote
control cannot be used. In
such cases, the doors can
be opened and the EV sys-
tem can be started by fol-
lowing the procedure below.
NOTICE
■In case of a smart key system
malfunction, o r other key
related problems
Take your vehicle with all the elec-
tronic keys provided with your
vehicle to your Toyota dealer.
Locking and unlocking
the doors

5418-2. Steps to take in an emergency
Owners Manual_USA_M42C01_en
8
When trouble arises
cannot be started, contact your Toy-
ota dealer.
■Stopping the EV system
Shift the shift position to P, set the
parking brake and press the power
switch as you no rmally do when
stopping the EV system.
■Replacing the key battery
As the above proc edure is a tempo-
rary measure, it is recommended
that the electronic key battery be
replaced immediate ly when the bat-
tery is depleted. ( P.497)
■Alarm
If a door is unlocked using the
mechanical key when the alarm sys-
tem is set, the alarm may be trig-
gered. ( P. 6 9 )
■Changing power switch modes
Release the brake pedal and press
the power switch in step 3 above.
The EV system does not start and
modes will be cha nged each time
the switch is pressed. ( P.234)
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 the doors locked. ( P. 7 0 )
2 Open the hood ( P.462).
3 Open the positive (+) battery
terminal cover.
While pressing on the claw, open
the cover as shown in the illustra-
If the 12-volt batter y is
discharged
The following procedures
may be used to start the EV
system if the vehicle’s 12-
volt battery is discharged.
You can also call your Toy-
ota dealer or a qualified
repair shop.
Restarting the EV system

5438-2. Steps to take in an emergency
Owners Manual_USA_M42C01_en
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When trouble arises
6 Open and close any of the
doors of your vehicle with the
power switch OFF.
7 Maintain the engine speed of
the second vehicle and start
the EV system of your vehi-
cle by turning the power
switch to ON.
8 Make sure the “READY” indi-
cator comes on. If the indica-
tor light does not come on,
contact your Toyota dealer.
9 Once the EV system has
started, remove the jumper
cables in the exact reverse
order from which they were
connected.
10 Close the positive (+) battery
terminal cover.
Once the EV system starts,
have the vehicle inspected at
your Toyota dealer as soon as
possible.
■Starting the EV system when
the 12-volt battery is dis-
charged
The EV system cannot be started by
push-starting.
■To prevent 12-volt battery dis-
charge
●Turn off the headlights, the air
conditioning system, the audio
system, etc. while the EV system
is off.
●Turn off any unnecessary electri-
cal components when the vehicle
is running at a low speed for an
extended period, such as in heavy
traffic.
■Charging the 12-volt battery
The electricity stored in the 12-volt
battery will discha rge gradually even
when the vehicle i s not in use, due
to natural dischar ge and the drain-
ing effects of certain electrical appli-
ances. If the vehicle is left for a long
time, the 12-volt battery may dis-
charge, and the EV system may be
unable to start. (The 12-volt battery
recharges automatically while the
EV system is operating.)
■When the 12-volt battery is
removed or discharged
●Information stored in the ECU is
cleared. When the 12-volt battery
is depleted, have the vehicle
inspected at your Toyota dealer.
●In some cases, it may not be pos-
sible to unlock the doors using the
smart key system when the 12-
volt battery is discharged. Use the
wireless remote c ontrol or the
mechanical key to lock or unlock
the doors.
●The EV system may not start on
the first attempt a fter the 12-volt
battery has recharged but will start
normally after the second attempt.
This is not a malfunction.
●The power switch mode is memo-
rized 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 discon-
necting 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 recon-
necting the 12-volt battery.
●If the 12-volt battery discharges, it
may not be possible to shift the
shift position to o ther positions. In
this case, the vehicle cannot be
towed without lifting both front
wheels because the front wheels
will be locked.
●The power back door (if equipped)