2021 TOYOTA HIGHLANDER HYBRID battery replacement

3334-6. Driving tips
4
Driving
HIGHLANDER HV_U
Use fluids that are appropriate
to the prevailing outside tem-
peratures.
• Engine oil
• Engine/power control unit coolant
• Washer fluid
Have a service technician
inspect the condition of the
12-volt battery.
 Have the vehicle fitted with
four snow tires or purchase a
set of tire chains for the front
tires.
Ensure that all tires are the same
size and brand, and that chains
match the size of the tires.
Perform the following according
to the driving conditions:
Winter driving tips
Carry out the necessary
preparations and inspec-
tions before driving the
vehicle in winter. Always
drive the vehicle in a man-
ner appropriate to the pre-
vailing weather conditions.
Pre-winter preparations
WARNING
■Driving with snow tires
Observe the following precautions
to reduce the risk of accidents.
Failure to do so m ay result in a
loss of vehicle control and cause
death or serious injury.
●Use tires of the specified size.
●Maintain the recommended
level of air pressure.
●Do not drive in excess of 75
mph (120 km/h), regardless of
the type of snow tires being
used.
●Use snow tires on all, not just
some wheels.
■Driving with tire chains
Observe the following precautions
to reduce the risk of accidents.
Failure to do so may result in the
vehicle being unable to be driven
safely, and may cause death or
serious injury.
●Do not drive in excess of the
speed limit specifi ed for the tire
chains being used, or 30 mph
(50 km/h), whichever is lower.
●Avoid driving on bumpy road
surfaces or over potholes.
●Avoid sudden acceleration,
abrupt steering, sudden brak-
ing and shifting operations that
cause sudden engine braking.
●Slow down sufficiently before
entering a curve to ensure that
vehicle control is maintained.
●Do not use the LTA (Lane Trac-
ing Assist) system.
NOTICE
■Repairing or replacing snow
tires
Request repairs or replacement of
snow tires from Toyota dealers or
legitimate tire retailers.
This is because the removal and
attachment of snow tires affects
the operation of the tire pressure
warning valves and transmitters.
Before driving the vehicle

3465-2. Using the air conditioning system and defogger
HIGHLANDER HV_U
■Customization
Some functions can be customized.
(  P.530)
Air conditioning sys-
tem lubricant type
Requires registered
technician to service
air conditioning sys-
tem
Flammable refrigerant
WARNING
■To prevent the windshield
from fogging up
Do not use the windshield defog-
ger switch during cool air opera-
tion in extremely humid weather.
The difference between the tem-
perature of the outside air and
that of the windshield can cause
the outer surface of the wind-
shield to fog up, blocking your
vision.
■When the outside rear view
mirror defoggers are operat-
ing
Do not touch the rear view mirror
surfaces when the outside rear
view mirror defoggers are on.
■When the windshield wiper
de-icer is operating
Do not touch the glass at lower
part of the windshield or to the
side of the fron t pillars when the
windshield wiper de-icer is on.
NOTICE
■To prevent 12-volt battery dis-
charge
Do not leave the air conditioning
system on longer than necessary
when the hybrid system is off.
■When repairing/replacing
parts of the air conditioning
system
Have repair/replacement per-
formed 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.

4066-2. Maintenance
HIGHLANDER HV_U
6-2.Maintenance
■Repair and replacement
It is recommended that genuine
Toyota parts be used for repairs to
ensure performanc e of each sys-
tem. If non-Toyota parts are used in
replacement or if a repair shop other
than a Toyota dealer performs
repairs, confirm the warranty cover-
age.
■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 ser-
vice information. They are well
informed about the operation of all
systems on your vehicle.
●Keep a copy of the repair order. It
proves that the maintenance that
has been performed is under war-
ranty coverage. If any problem
should arise while your vehicle is
under warranty, your Toyota
dealer will promptly take care of it.
General maintenance should be
performed on a daily basis. This
can be done by yourself or by a
Toyota dealer.
Scheduled maintenance should
be performed at specified inter-
vals according to the mainte-
nance schedule.
For details about maintenance
items and schedules, refer to the
“Scheduled Maintenance Guide” or
“Owner’s Manual Supplement”.
Maintenance require-
ments
To ensure safe and econom-
ical driving, day-to-day care
and regular maintenance
are essential. It is the
owner’s responsibility to
perform regular checks.
Toyota recommends the fol-
lowing maintenance:
WARNING
■If your vehicle is not properly
maintained
Improper maintenance could
result in serious damage to the
vehicle and possible death or seri-
ous injury.
■Handling of the 12-volt bat-
tery
●Engine exhaust, some of its
constituents, and a wide variety
of automobile components con-
tain 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 pro-
duced by component wear con-
tain 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 con-
tain lead and lead compounds
which are known to cause brain
damage. Wash your hands after
handling. ( P.421)
General maintenance
Scheduled maintenance

4236-3. Do-it-yourself maintenance
6
Maintenance and care
HIGHLANDER HV_U
WARNING
●Do not cause sparks by touch-
ing 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 electro-
lyte.
●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 insuf-
ficient ventilation.
■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 regard-
ing 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 near-
est medical facility.
●If electrolyte gets on your skin
Wash the affected area thor-
oughly. If you fee l pain or burn-
ing, get medical attention
immediately.
●If electrolyte gets on your
clothes
It can soak through clothing on
to your skin. Imm ediately take
off the clothing and follow the
procedure above if necessary.
●If you accidentally swallow elec-
trolyte
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. Failu re 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.
■When handling the 12-volt
battery
P. 5 0 2
NOTICE
■When recharging the 12-volt
battery
Never recharge t he 12-volt bat-
tery while the hybrid system is
operating. Also, be sure all acces-
sories are turned off.

5027-2. Steps to take in an emergency
HIGHLANDER HV_U• Use the exhaust hose that was
attached to the 12-volt battery
before replacing an d confirm that
it is firmly connected to the hole
section of t he vehicle.
• Use the exhaust hole plug
included with the 12-volt battery
replaced 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.)
Exhaust hole
Exhaust hole plug
Exhaust hose
Hole section of the vehicle
For details, consult your Toyota
dealer.
WARNING
■When removing the 12-volt
battery terminals
Always remove the negative (-)
terminal first. If the positive (+) ter-
minal contacts any metal in the
surrounding area when the posi-
tive (+) terminal is removed, a
spark may occur, l eading to a fire
in addition to electrical shocks
and death or serious injury.
■When disconnecting the
12-volt battery
Do not disconnect the negative (-)
terminal on the body side. The
disconnected negative (-) terminal
may touch the positive (+) termi-
nal, which may cause a short and
result in death or serious injury.
■Avoiding 12-volt battery fires
or explosions
Observe the following precautions
to prevent accidentally igniting the
flammable gas that may be emit-
ted from the 12-volt battery:
●Make sure each jumper cable is
connected to the correct termi-
nal and that it is not unintention-
ally in contact with any other
than the intended terminal.
●Do not allow the other end of
the jumper cable connected to
the “+” terminal to come into
contact with any other parts or
metal surfaces in the area, such
as brackets or unpainted metal.
●Do not allow the + and - clamps
of the jumper cables to come
into contact with each other.
●Do not smoke, use matches,
cigarette lighter s or allow open
flame near the 1 2-volt battery.
■12-volt battery precautions
The 12-volt battery contains poi-
sonous and corrosive acidic elec-
trolyte, while related parts contain
lead and lead compounds.
Observe the following precautions
when handling the 12-volt battery:
●When working with the 12-volt
battery, always wear safety
glasses and take care not to
allow any battery fluids (acid) to
come into contact with skin,
clothing or the vehicle body.
●Do not lean over the 12-volt bat-
tery.

5037-2. Steps to take in an emergency
7
When trouble arises
HIGHLANDER HV_U
WARNING
●In the event that battery fluid
comes into contact with the skin
or eyes, immediately wash the
affected area with water and
seek medical attention. Place a
wet sponge or cloth over the
affected area until medical
attention can be received.
●Always wash your hands after
handling the 12-volt battery sup-
port, terminals, and other bat-
tery-related parts.
●Do not allow child ren near the
12-volt battery.
■After recharging the 12-volt
battery
Have the 12-volt battery
inspected at your Toyota dealer
as soon as possible.
If the 12-volt battery is deteriorat-
ing, continued use may cause the
12-volt battery to emit a malodor-
ous gas, which may be detrimen-
tal to the health of passengers.
■When replacing the 12-volt
battery
●When the vent plug and indica-
tor are close to the hold down
clamp, the battery fluid (sulfuric
acid) may leak.
●For information regarding
12-volt battery replacement,
contact your Toyota dealer.
●After replacing, securely attach
the exhaust hose and exhaust
hole plug to the exhaust hole of
the replaced 12-volt battery. If
not properly installed, gases
(hydrogen) may leak into the
vehicle interior, and there is the
possible danger of the gas ignit-
ing and exploding.
NOTICE
■When handling jumper cables
When connecting the jumper
cables, ensure that they do not
become entangled in the cooling
fan or belt.
■To prevent damaging the
vehicle
The exclusive jump starting termi-
nal is to be used when charging
the 12-volt battery from another
vehicle in an emergency. It cannot
be used to jump start another
vehicle.

5148-1. Specifications
HIGHLANDER HV_U
*: The fluid capacity is a reference quantity.If replacement is necessary, contact your Toyota dealer.
*: The fluid capacity is a reference quantity.If replacement is necessary, contact your Toyota dealer.
Ignition system (spark plug)
MakeDENSO FC16HR-Q8
Gap0.031 in. (0.8 mm)
NOTICE
■Iridium-tipped spark plugs
Use only iridium-tipped spark plugs. Do not adjust the spark pl ug gap.
Electrical system (12-volt battery)
Open voltage at 68°F (20°C):
12.0 V or higher
(Turn the power switch off and turn on the
high beam headlights for 30 seconds.)
Charging rates5 A max.
Hybrid transmission
Fluid capacity*4.6 qt. (4.4 L, 3.9 Imp. qt.)
Fluid typeToyota Genuine ATF WS
NOTICE
■Hybrid transmission fluid type
Using transmission fluid other than the above type may cause ab normal
noise or vibration, or ultimately damage the transmission of yo ur vehicle.
Rear differential (rear electric motor)
Fluid capacity*1.8 qt. (1.7 L, 1.5 Imp. qt.)
Fluid typeToyota Genuine ATF WS