2021 TOYOTA AVALON HYBRID battery replacement

851-3. Hybrid system
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For safety and security
NOTICE
■Hybrid battery (traction battery) air intake vent
●Make sure not to block the air intake vent with anything, such as a seat
cover, plastic cover, or luggage. The hybrid battery (traction battery) may
overheat and be damaged.
●When dust etc. has accumulated in the air intake vent, clean it with a vac-
uum cleaner to prevent the vent from clogging.
●Do not get water or foreign materials in the air intake vent as this may
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5c0003000b00570055004400460057004c0052005100030045[attery).
●Do not carry large amounts of water such as water cooler bottles in the
vehicle. If water spills onto the hybrid battery (traction battery), the battery
may be damaged. Have the vehicle inspected by your Toyota dealer.
●There is a filter installed to the air intake vent. When the filter remains
noticeably dirty even after cleaning the air intake vent, filter cleaning or
replacement is recommended. When cleaning the filter, refer to P. 434.

3485-1. Using the air conditioning system and defogger
WARNING
■To prevent the windshield from fogging up
●Do not use during cool air operation in extremely humid weather.
The difference between the temperature of the outside air and that of the
windshield can cause the outer surface of the windshield to fog up, block-
ing your vision.
■To prevent burns
Do not touch the rear view mirror surfaces when the outside rear view mirror
defoggers are on.
NOTICE
■To prevent 12-volt battery discharge
Do not leave the air conditioning system on longer than necessary when the
hybrid system is stopped.
■When repairing/replacing parts of the air conditioning system
Have repair/replacement performed by your Toyota dealer.
When a part of the air conditioning system, such as the evaporator, is to be
replaced, it must be replaced with a new one.
●Do not place anything on the instrument
panel which may cover the air outlets.
Otherwise, air flow may be obstructed,
preventing the windshield defoggers
from defogging.

3936-2. Maintenance
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Maintenance and care
■Repair and replacement
It is recommended that genuine Toyota parts be used for repairs to ensure
performance of each system. If non-Toyota parts are used in replacement or if
a repair shop other than a Toyota dealer performs repairs, confirm the war-
ranty coverage.
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540058004c005500480047>
After the required maintenance is performed according to the maintenance
schedule, please reset the message.
To reset the message, perform the following procedure:
Select on the multi-information display using the meter control switches
on the steering wheel. (P. 111)
Select and then press and hold .
Select “Scheduled Maintenance” and then press .
Select “Yes” and then press .
A message will be displayed on the multi-information display when the
reset procedure has been completed.
■Allow inspection and repairs to be performed by a Toyota dealer
●Toyota technicians are well-trained specialists and are kept up to date with
the latest service information. They are well informed about the operations
of all systems on your vehicle.
●Keep a copy of the repair order. It proves that the maintenance that has
been performed is under warranty coverage. If any problem should arise
while your vehicle is under warranty, your Toyota dealer will promptly take
care of it.
WARNING
■If your vehicle is not properly maintained
Improper maintenance could result in serious damage to the vehicle and
possible death or serious injury.
■Important health and safety information
●Engine exhaust, some of its constituents, and a wide variety of automobile
components contain or emit chemicals known to the State of California to
cause cancer and birth defects and other reproductive harm. Work in a
well ventilated area.
●Oils, fuels and fluids contained in vehicles as well as waste produced by
component wear contain or emit chemicals known to the State of
California to cause cancer and birth defects or other reproductive harm.
Avoid exposure and wash any affected area immediately.
●12-volt battery posts, terminals and related accessories contain lead and
lead compounds which are known to cause brain damage. Wash your
hands after handling. (P. 411)
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4136-3. Do-it-yourself maintenance
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Maintenance and care
WARNING
■Chemicals in the 12-volt battery
The 12-volt battery contains poisonous and corrosive sulfuric acid and may
produce hydrogen gas which is flammable and explosive. To reduce the risk
of death or serious injury, take the following precautions 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 battery in a garage or closed room where there is insufficient ventila-
tion.
■How to recharge the 12-volt battery
Only perform a slow charge (5 A or less). The 12-volt battery may explode if
charged at a quicker rate.
■Emergency measures regarding electrolyte
●If electrolyte gets in your eyes
Flush your eyes with clean water for at least 15 minutes and get immedi-
ate 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 cloth-
ing and follow the procedure above if necessary.
●If you accidentally swallow electrolyte
Drink a large quantity of water or milk. Get emergency medical attention
immediately.
■When disconnecting the 12-volt battery
Do not disconnect the negative (-) terminal on the body side. The discon-
nected negative (-) terminal may touch the positive (+) terminal, which may
cause a short and result in death or serious injury.
■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 compartment, causing a fire or
explosion.
For replacement of the 12-volt battery, contact your Toyota dealer.

4917-2. Steps to take in an emergency
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When trouble arises
■When replacing the 12-volt battery
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53004800440051000300350048004a0058004f00440057004c[ons).
●Use a 12-volt battery that the case size is same as the previous one (LN2),
20 hour rate capacity (20HR) is equivalent (64Ah) or greater, and perfor-
mance rating (CCA) is equivalent (356A) or greater.
• If the sizes differ, the 12-volt battery cannot be properly secured.
• If the 20 hour rate capacity is low, even if the time period where the vehi-
cle 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.
For details, consult your Toyota dealer. ●After replacing, firmly 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 replaced or
the one installed on the battery prior
to the replacement. (Depending on
the 12-volt battery to be replaced, the
exhaust hole may be plugged.)
Exhaust hole plug
Exhaust hole
Exhaust hose
Hole section of the vehicle
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5078-1. Specifications
8
Vehicle specifications
*: The fluid capacity is a reference quantity.
If replacement is necessary, contact your Toyota dealer.
*: Minimum pedal clearance when depressed with a force of 67 lbf (300 N, 31
kgf) while the hybrid system is operating.
Electrical system
12-volt battery
Open voltage at
68F (20C):12.0 V or higher
If the voltage is lower than the standard value,
charge the battery.
(When checking the voltage, after turning the
power switch off, wait for 30 seconds with the
high beam headlights illuminated, then turn the
high beam headlights off and check the voltage.)
Charging rates5 A max.
Hybrid transmission
Fluid capacity*4.1 qt. (3.9 L, 3.4 Imp. qt.)
Fluid type Toyota Genuine ATF WS
NOTICE
■Hybrid transmission fluid type
Using transmission fluid other than the above type may cause abnormal
noise or vibration, or ultimately damage the transmission of your vehicle.
Brakes
Pedal clearance*3.3 in. (85 mm)
Pedal free play 0.04  0.24 in. (1  6 mm)
Brake pad wear limit0.04 in. (1.0 mm)
Fluid typeSAE J1703 or FMVSS No.116 DOT 3
SAE J1704 or FMVSS No.116 DOT 4
Steering
Free play Less than 1.2 in. (30 mm)