2019 Lexus ES300h key battery

3396-3. Do-it-yourself maintenance
6
Maintenance and care
filter.
■If the electronic key battery is depleted
The following symptoms may occur:
●The smart access system with push-but-
ton start and wireless remote control will
not function properly.
●The operationa l range will be reduced.
Prepare the following before replacing
the battery:
Flathead screwdriver
 Small flathead screwdriver
 Lithium battery CR2032
■Use a CR2032 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 manufacturer.
●Dispose of used batteries according to
the local laws.
1Take out the mechanical key.
NOTICE
■When using the air conditioning sys-
tem
●Make sure that a filter is always
installed.
Using the air conditioning system with-
out a filter may cause damage to the
system.
●The filter is replaceable.
When cleaning the filter, do not clean
with water or an air gun.
■To prevent damage to the filter cover
When moving the filter cover in the
direction of arrow to release the fitting,
pay attention not to apply excessive force
to the claws. Otherwise, the claws may
be damaged.
Electronic key battery
Replace the battery with a new one
if it is depleted.
Items to prepare
Replacing the battery

3406-3. Do-it-yourself maintenance
2Remove the cover.
To prevent damage to the key, wrap the tip
of the screwdriver with tape.
3Remove the depleted battery.
Insert a new battery with the “+” terminal
facing up.
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
could result in death or serious injury.
NOTICE
■When replacing the battery
Use a screwdriver of appropriate size.
Applying excessive 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 com-
ponent inside the remote control.
●Do not bend either of the battery ter-
minals.

349
7
7
When trouble arises
When trouble arises
7-1. Essential informationEmergency flashers.................. 350
If your vehicle has to be stopped in an emergency .......................... 350
If the vehicle is trapped in rising water............................................. 351
7-2. Steps to take in an emergency If your vehicle needs to be towed.353
If you think something is wrong ..... 356
If a warning light turns on or a warning buzzer sounds ....... 358
If a warning message is displayed 368
If you have a flat tire.................. 372
If the hybrid system will not start ... 379
If you lose your keys ................. 380
If the fuel filler door cannot be opened......................................... 381
If the electronic key does not operate properly ..................... 381
If the 12-volt battery is discharged 384
If your vehicle overheats ........ 388
If the vehicle becomes stuck . 391

3717-2. Steps to take in an emergency
7
When trouble arises
schedule* should be performed soon.
Comes on approximately 4500 miles
(7200 km) after the message has been
reset. If necessary, perform maintenance.
Please reset the message after the mainte-
nance is performed. ( P.309)
*: Refer to the separa te “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
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.309)
*: Refer to the separa te “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 engine 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.309)
■If “Oil Maintenance Required” is dis-
played
Indicates that the engine oil should be
changed.
Check and change the en gine oil, and oil fil-
ter by your Lexus deal er. After changing the
engine oil, make sure to reset the message.
(  P.320)
■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 indicates the need for
referring to Owner’
s Manual is dis-
played
●If any of the following messages are
shown on the multi-information display,
follow the instructions.
• “Engine Coolant Temp High” ( P.388)
●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 System Malfunction”
• “Oil Pressure Low”
• “Hybrid system stopped”
• “Engine stopped”
●If “Low Auxiliary Battery” is shown
• When the display goes off after several
seconds
*:
Maintain the hybrid system operation for
more than 15 minutes and charge the 12-
volt battery.
• When the display does not go off:
Start up the hybrid system using the proce-
dures for “If the 12-volt battery is dis-
charged” ( P.384).
*: Displays for about 6 seconds
●If “Maintenance required for Traction bat-
tery cooling Parts” is shown, the filters
may be clogged, the air intake vents may
be blocked, or there may be a gap in the
duct. Therefore, perform the following
correction procedure.
• If the air intake vent s and filters of the
hybrid battery (traction battery) are dirty,
perform the procedure on P.304 to

3797-2. Steps to take in an emergency
7
When trouble arises
One of the following may be the cause
of the problem:
The electronic key may not be func-
tioning properly. ( P.383)
 There may not be sufficient fuel in
the vehicle’s tank.
Refuel the vehicle. ( P.161)
 There may be a malfunction in the
immobilizer system. ( P.60)
 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.
One of the following may be the cause of the problem:

The 12-volt battery may be dis-
charged. ( P.384)
 The 12-volt battery terminal con-
nections may be lo ose or corroded.
( P.325)
One of the following may be the cause
of the problem:
 The 12-volt battery may be dis-
charged. ( P.384)
 One or both of the 12-volt battery
terminals may be disconnected.
( P.325)
Contact your Lexus dealer if the problem
cannot be repaired, or if repair procedures
are unknown.
When the hybrid syst em does not start,
the following steps can be used as an
interim measure to start the hybrid sys-
tem if the power switch is functioning
normally.
Do not use this starting procedure
except in cases of emergency.
1 Press the parking brake switch to
check that the parking brake is set.
(P.146)
Parking brake indicator will come on.
2 Shift the shift lever to P.
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.135)
The interior lights and head-
lights are dim, or the horn does
not sound or sounds at a low vol-
ume.
The interior lights and head-
lights do not turn on, or the horn
does not sound.
Starting the hybrid system in an
emergency

3817-2. Steps to take in an emergency
7
When trouble arises
Remove the cover inside the trunk and
pull the lever.
Using the lever to open the fuel filler door
may not allow for an adequate reduction in
fuel tank pressure before refueling. To pre-
vent 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, f ill the fuel tank care-
fully and slowly.
■When the electronic key does not work
properly
●Make sure that the smart access system
with push-button start has not been deac-
tivated using the Remote Touch or at your
Lexus dealer. If it is off, turn the function
on.
●Check if battery-saving mo de is set. If it is
set, cancel the function. ( P.103)
Use the mechanical key ( P.90) in
order to perform th e following opera-
tions:
If the fuel filler door cannot
be opened
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, the following procedure
can be used to open the fuel filler
door.
Opening the fuel filler door
If the electronic key does not
operate properly
If communication between the
electronic key and vehicle is inter-
rupted ( P.103) 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.
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 as soon as possible.
Locking and unlocking the
doors, opening the trunk and
using the key linked functions

3837-2. Steps to take in an emergency
7
When trouble arises
1Ensure that the shift lever is in P and
depress the brake pedal.
2 Touch the Lexus emblem side of the
electronic key to the power switch.
When the electronic key is detected, a
buzzer sounds and the power switch will
turn to ON mode.
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
Set the parking brake, shift the shift lever to
P and press the power switch as you nor-
mally do when stopping the hybrid system.
■Electronic key battery
As the above procedure is a temporary
measure, it is recomme nded that the elec-
tronic key battery be replaced immediately
when the battery is depleted. ( P.339)
■Changing power switch modes
Release the brake pe dal 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.137)Starting the hybrid system

3847-2. 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 using the following procedure.
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.63)
2 Open the hood ( P.316) and
open the fuse box cover.
Push the tab in and lift the lid off.
3 Open the exclusive jump starting
terminal cover.
4 Connect a positive jumper cable clamp to on your vehicle and connect the
clamp on the other end of the positive cable to on the second vehicle.
If the 12-volt battery is dis-
charged
The following procedures may be
used to start the hybrid system if the
12-volt battery is discharged.
You can also call your Lexus dealer
or a qualified repair shop.
Restarting the hybrid system
A
B