2020 Lexus ES300h 12 volt

3276-3. Do-it-yourself maintenance
6
Maintenance and care
switch mode to the status it was in before
the 12-volt battery was disconnected.
Make sure to turn off the power switch
before disconnect the 12-volt battery.
Take extra care when connecting the 12-
volt battery if the power switch mode
prior to discharge is unknown.
If the hybrid system will not start even after
multiple attempts at all methods above,
contact your Lexus dealer.
Lift the luggage mat up.
WARNING
■Chemicals in the 12-volt battery
The 12-volt battery contains poisonous
and corrosive sulfuric acid and may pro-
duce hydrogen gas which is flammable
and explosive. To reduce the risk of death
or serious injury, take the following pre-
cautions while working on or near the 12-
volt battery:
●Do not cause sparks by touching the
12-volt battery terminals with tools.
●Do not smoke or light a match near the
12-volt battery.
●Avoid contact with eyes, skin and
clothes.
●Never inhale or swallow electrolyte.
●Wear protective safety glasses when
working near the 12-volt battery.
●Keep children away from the 12-volt
battery.
■Where to safely charge the 12-volt
battery
Always charge the 12-volt battery in an
open area. Do not charge the 12-volt bat-
tery in a garage or closed room where
there is insufficient ventilation.
■How to recharge the 12-volt battery
Recharge at a current of 5 A or less and
make sure that the recharging period
does not exceed a total of 12 hours.
■Emergency measures regarding
electrolyte
●If electrolyte gets in your eyes
Flush your eyes with clean water for at
least 15 minutes and get immediate
medical attention. If possible, continue
to apply water with a sponge or cloth
while traveling to the nearest medical
facility.
●If electrolyte gets on your skin
Wash the affected area thoroughly. If
you feel pain or burning, get medical
attention immediately.
●If electrolyte gets on your clothes
It can soak through clothing on to your
skin. Immediately take off the clothing
and follow the procedure above if nec-
essary.
●If you accidentally swallow electrolyte
Drink a large quantity of water or milk.
Get emergency medical attention
immediately.
■When replacing the 12-volt battery
Use a 12-volt battery designed for this
vehicle. Failure to do so may cause gas
(hydrogen) to enter the passenger com-
partment, causing a fire or explosion.
For replacement of the 12-volt battery,
contact your Lexus dealer.
NOTICE
■When recharging the 12-volt battery
Never recharge the 12-volt battery while
the hybrid system is operating. Also, be
sure all accessories are turned off.
Removing the 12-volt battery
cover

3286-3. Do-it-yourself maintenance
Make sure that the 12-volt battery ter-
minals are not corroded and that there
are no loose connections, cracks, or
loose clamps.Terminals
Hold-down clamp
Check the 12-volt battery condition by
indicator color. Blue: Good condition
Red: Charging is necessary.Have the vehicle inspected by your Lexus
dealer.
Clear: Replacement is necessary.
Have the 12-volt battery checked by your
Lexus dealer.
Exterior
Checking 12-volt battery condi-
tion
A
B
A
B
C

355
7
7
When trouble arises
When trouble arises
7-1. Essential informationEmergency flashers.................. 356
If your vehicle has to be stopped in an emergency .......................... 356
If the vehicle is trapped in rising water............................................ 357
7-2. Steps to take in an emergency If your vehicle needs to be towed........................................................ 359
If you think something is wrong ........................................................ 362
If a warning light turns on or a warning buzzer sounds ....... 364
If a warning message is displayed ........................................................ 374
If you have a flat tire.................. 378
If the hybrid system will not start ........................................................ 385
If you lose your keys ................. 387
If the fuel filler door cannot be opened........................................ 387
If the electronic key does not operate properly .................... 388
If the 12-volt battery is discharged ........................................................ 390
If your vehicle overheats ........ 395
If the vehicle becomes stuck 398

3567-1. Essential information
7-1.Essential information
Press the switch to flash all of the turn
signal lights.
To turn them off, press the switch once
again.
■Emergency flashers
●If the emergency flashers are used for a
long time while the hybrid system is not
operating (while the “READY” indicator
is not illuminated), the 12-volt battery may
discharge.
●If any of the SRS airbags deploy (inflate)
or in the event of a strong rear impact, the
emergency flashers will turn on automati-
cally.
The emergency flashers will turn off auto-
matically after operating for approxi-
mately 20 minutes. To manually turn the
emergency flashers off, press the switch
twice.
(The emergency flashers may not turn on
automatically dependin g on the force of
the impact and conditions of the colli-
sion.)
1 Steadily step on the brake pedal
with both feet and firmly depress it.
Do not pump the brake pedal repeatedly
as this will increase the effort required to
slow the vehicle.
2Shift the shift lever to N.
If the shift lever is shifted to N
3 After slowing down, stop the vehi-
cle in a safe place by the road.
4 Stop the hybrid system.
If the shift lever cannot be shifted to
N
3 Keep depressing the brake pedal
with both feet to reduce vehicle
speed as much as possible.
4 To stop the hybrid system, press
and hold the power switch for 2
consecutive seconds or more, or
Emergency flashers
The emergency flashers are used to
warn other drivers when the vehicle
has to be stopped in the road due to
a breakdown, etc.
Operating instructions
If your vehicle has to be
stopped in an emergency
Only in an emergency, such as if it
becomes impossible to stop the
vehicle in the normal way, stop the
vehicle using the following proce-
dure:
Stopping the vehicle

3717-2. Steps to take in an emergency
7
When trouble arises
■Brake hold operated indicator (warning buzzer)
■Hybrid system overheat warning light* (warning buzzer)
*: This light illuminates on the multi-information display.
■Master warning light (warning buzzer)
■Warning buzzer
In some cases, the bu zzer may not be heard
due to being in a noisy location or audio
sound.
■Front passenger detection sensor, seat
belt reminder and warning buzzer
●If luggage is placed on the front passen-
ger seat, the front passenger detection
sensor may cause th e warning light to
flash and the warning buzzer to sound
even if a passenger is not sitting in the
seat.
●If a cushion is placed on the seat, the sen-
sor may not detect a passenger, and the
warning light may not operate properly.
■SRS warning light
This warning light system monitors the air-
bag sensor assembly, fr ont impact sensors,
side impact sensors (front door), side
impact sensors (front), side impact sensors
(rear), driver’s seat position sensor, driver’s
seat belt buckle switch, front passenger
occupant classification system (ECU and
sensors), “AIR BAG ON” indicator light, “AIR BAG OFF” indicator light, front pas-
senger’s seat belt buckle switch, seat belt
pretensioners, airbags, interconnecting wir-
ing and power sources. (
P.28)
■Electric power steering system warning
light (warning buzzer)
When the 12-volt battery charge becomes
insufficient or the voltage temporarily
drops, the electric power steering system
warning light may come on and the warning
buzzer may sound.
■When the tire pressure warning light
comes on
Inspect the tires to check if a tire is punc-
tured.
If a tire is punctured:  P.378
If none of the tires are punctured:
Turn the power switch off then turn it to ON
mode. Check if the tire pressure warning
light comes on or blinks.
Warning lightDetails/Actions
(flashes)
Indicates a malfunction in the brake hold system
 Have the vehicle inspected by your Lexus dealer immediately.
Warning lightDetails/Actions
Indicates that the hybrid system has overheated
Stop the vehicle in a safe place. Handling method ( P.396)
Warning lightDetails/Actions
A buzzer sounds and the warning light comes on and flashes to indicate
that the master warning system has detected a malfunction.
 P.374

3767-2. Steps to take in an emergency
■If “Traction Battery Needs to be Pro-
tected Shift into P to Restart” is dis-
played
This message is displayed when the hybrid
battery (traction battery) charge has
become extremely low because the shift
lever has been left in N for a certain amount
of time.
When operating the vehicle, shift to P and
restart the hybrid system.
■If “Shift to P Before exiting vehicle” is
displayed
Message is displayed when the driver’s
door is opened with out turning the power
switch off with the shift lever in any position
other than P.
Shift the shift lever to P.
■If “Shift is in N Release accelerator
before shifting” is displayed
The accelerator pedal has been depressed
when the shift lever is in N.
Release the accelerator pedal and shift the
shift lever to D or R.
■If “Accelerator pedal is pressed” is dis-
played
The accelerator pedal has been depressed
when the shift lever is in P.
Release the accelerator pedal.
■If “Press brake when vehicle is stopped
Hybrid system may overheat” is dis-
played
The message may be displayed when the
accelerator pedal is depressed to hold the
vehicle while the vehicle is stopped on an
incline, etc. The hybrid system may over-
heat. Release the accelerator pedal and
depress the brake pedal.
■If “Auto Power Off to Conserve Battery”
is displayed
Power was turned off due to the automatic
power off function. Next time when starting
the hybrid system, operate the hybrid sys-
tem for approximately 5 minutes to
recharge the 12-volt battery.
■If “High Power Cons umption Power to
Climate Temporarily Limited” is dis-
played
Turn off unnecessary electronic equipment
to reduce power consumption.
Please wait until the power supply returns to
normal.
■If “Headlight System Malfunction Visit
Your Dealer” is displayed
The following systems may be malfunction-
ing. Have the vehicle inspected by your
Lexus dealer immediately.
●The LED headlight system
●AFS (Adaptive Front-lighting System)
●The automatic headlight leveling system
(if equipped)
●Automatic High Beam
■If “Radar Cruise Control Unavailable
See Owner’s Manual” is shown
The dynamic radar cruise control with full-
speed range system is suspended tempo-
rarily or until the pr oblem shown in the mes-
sage is resolved. (causes and coping
methods: P.178)
■If “Radar Cruise Control Unavailable” is
shown
The dynamic radar cruise control with full-
speed range system cannot be used tempo-
rarily. Use the system when it becomes
available again.
■If “Front Camera Unav ailable” or “Front
Camera Unavailable See Owner’s
Manual” is displayed
The following systems may be suspended
until the problem shown in the message is
resolved. ( P.178, 370)
●PCS (Pre-Collision System)
●LTA (Lane Tracing Assist)
●Automatic High Beam
●RSA (Road Sign Assist) (if equipped)
●Dynamic radar cruise control with full-
speed range
■If “Maintenance Required Soon” is dis-
played
Indicates that all maintenance according to

3777-2. Steps to take in an emergency
7
When trouble arises
the driven distance on the maintenance
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.312)
*: 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.312)
*: 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.312)
■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.323)
■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.395)
●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.390).
*: Displays for about 6 seconds
●If “Maintenance required for Traction bat-
tery cooling parts” is shown, the filter may
be clogged, the air intake vent 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,

3787-2. Steps to take in an emergency
perform the procedure on P.343 to clean
them.
• If the warning message is shown when the air intake vents and filters of the
hybrid battery (traction battery) are not
dirty, have the vehicle inspected by your
Lexus dealer.
 Stop the vehicle in a safe place on a
hard, flat surface.
 Set the parking brake.
 Shift the shift lever to P.
 Stop the hybrid system.
 Turn on the emergency flashers.
( P.356)
NOTICE
■If “High Power Consumption Power
to Climate Temporarily Limited” 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.
■If “Low Auxiliary Battery” is displayed
frequently
The 12-volt battery may have deterio-
rated. As the battery may discharge in
this state when left unattended, have the
battery inspected by your Lexus dealer.
If you have a flat tire
Your vehicle is equipped with a
spare tire. The flat tire can be
replaced with the spare tire.
For details about tires: P.329
WARNING
■If you have a flat tire
Do not continue driving with a flat tire.
Driving even a short distance with a flat
tire can damage the tire and the wheel
beyond repair, which could result in an
accident.
Before jacking up the vehicle