2023 TOYOTA HIGHLANDER battery

3806-2. Maintenance
The OBD system determines
that a problem exists some-
where in the emission control
system. Your vehicle may not
pass the I/M test and may need
to be repaired. Contact your
Toyota dealer to service the
vehicle.
When the battery is discon-
nected or discharged
Readiness codes that are set
during ordinary driving are erased.
Also, depending on your driving
habits, the readiness codes may
not be completely set.
When the fuel tank cap is
loose
Vehicle exterior
ItemsCheck points
Doors
• Do the doors
operate
smoothly?
Engine hood
• Does the engine hood lock system
work properly?
Fluid leaks
• There should not be any signs of
fluid leakage
after the vehicle
has been parked.
Tires
• Is the tire infla-tion pressure
correct?
• The tires should not be damaged
or excessively
worn.
• Have the tires been rotated
according to the
maintenance
schedule?
• The wheel nuts should not be
loose.
Windshield
wipers/rear
window wiper
• The wiper blades should not show
any signs of
cracking, split-
ting, wear, con-
tamination or
deformation.
• The wiper blades should clear the
windshield/rear
window without
streaking or skip-
ping.
Emission inspection
and maintenance (I/M)
programs
Some states have vehicle
emission inspection pro-
grams which include OBD
(On Board Diagnostics)
checks. The OBD system
monitors the operation of
the emission control sys-
tem.
If the malfunction indica-
tor lamp comes on
Your vehicle may not pass
the I/M test in the follow-
ing situations:

3826-3. Do-it-yourself maintenance
6-3.Do-it-yourself maintenance
Do-it-yourself ser vice
precautions
If you perform maintenance
by yourself, be sure to fol-
low the correct procedure
as given in these sections.
Maintenance
ItemsParts and tools
Battery condi-
tion (P.391)
• Warm water
• Baking soda
•Grease
• Conventional
wrench (for ter-
minal clamp
bolts)
Brake fluid
level ( P.390)
• FMVSS No.116
DOT 3 or SAE
J1703 brake fluid
• Rag or paper towel
• Funnel (used only for adding
brake fluid)
Engine cool-
ant level
( P.389)
• “Toyota Super
Long Life Cool-
ant” or a similar
high quality eth-
ylene gly-
col-based
non-silicate,
non-amine,
non-nitrite and
non-borate cool-
ant with long-life
hybrid organic
acid technology
For the U.S.A.:
“Toyota Super
Long Life Cool-
ant” is pre-mixed
with 50% cool-
ant and 50%
deionized water.
For Canada:
“Toyota Super
Long Life Cool-
ant” is pre-mixed
with 55% cool-
ant and 45%
deionized water.
• Funnel (used only for adding
coolant)
Engine oil level
( P.386)
• “Toyota Genuine
Motor Oil” or
equivalent
• Rag or paper towel
• Funnel (used only for adding
engine oil)
Fuses
( P.412)• Fuse with same
amperage rating
as original
ItemsParts and tools

3836-3. Do-it-yourself maintenance
6
Maintenance and care
Headlight aim
( P.414)• Phillips-head
screwdriver
Light bulbs
( P.415)
• Bulb with same
number and
wattage rating as
original
• Phillips-head screwdriver
• Flathead screw- driver
• Wrench
Radiator and
condenser
(  P.390)

Tire inflation
pressure
( P.405)• Tire pressure
gauge
• Compressed air source
Washer fluid
( P.392)
• Water or washer
fluid containing
antifreeze (for
winter use)
• Funnel (used only for adding
water or washer
fluid)
WARNING
The engine compartment contains
many mechanisms and fluids that
may move suddenly, become hot,
or become electrically energized.
To avoid death or serious injury,
observe the following precautions.
■When working on the engine
compartment
●Keep hands, clothing and tools
away from the moving fan and
engine drive belt.
ItemsParts and tools●Be careful not to touch the
engine, radiator, exhaust mani-
fold, etc. right a fter driving as
they may be hot. Oil and other
fluids may also be hot.
●Do not leave anything that may
burn easily, such as paper and
rags, in the engine compart-
ment.
●Do not smoke, cause sparks or
expose an open flame to fuel or
the battery. Fuel and battery
fumes are flammable.
●Be extremely cautious when
working on the battery. It con-
tains poisonous and corrosive
sulfuric acid.
■When working near the elec-
tric cooling fan or radiator
grille
Be sure the engine switch is off.
With the engine switch in ON, the
electric cooling fa n may automati-
cally start to run if the air condi-
tioning is on and/or the coolant
temperature is high. ( P.390)
■Safety glasses
Wear safety glasses to prevent
flying or falling material, fluid
spray, etc. from getting in your
eyes.
NOTICE
■If you remove the air cleaner
filter
Driving with the air cleaner filter
removed may cause excessive
engine wear due to dirt in the air.

3866-3. Do-it-yourself maintenance
Engine coolant reservoir ( P.389)
Fuse boxes ( P.412)
Engine oil filler cap ( P.387)
Engine oil level dipstick ( P.386)
Battery ( P.391)
Brake fluid reservoir ( P.390)
Washer fluid tank ( P.392)
Electric cooling fan
Condenser ( P.390)
Radiator ( P.390)
With the engine at operating
temperature and turned off,
check the oil level on the dip- stick.
■Checking the engine oil
1 Park the vehicle on level
ground. After warming up the
engine and turning it off, wait
Engine compar tment
Components
Checking and adding the
engine oil

3916-3. Do-it-yourself maintenance
6
Maintenance and care
Check the battery as follows.
■Battery exterior
Make sure that the battery termi-
nals are not corroded and that
there are no loose connections,
cracks, or loose clamps.
Terminals
Hold-down clamp
■Before recharging
When recharging, the battery pro-
duces hydrogen gas which is flam-
mable and explosive. Therefore,
observe the followi ng precautions
before recharging:
●If recharging with the battery
installed on the vehicle, be sure to
disconnect the ground cable.
●Make sure the power switch on
the charger is off when connecting
and disconnecting the charger
cables to the battery.
■After recharging/reconnecting
the battery
The engine may not start. Follow the
procedure below to initialize the sys-
tem.
1 Shift the shift lever to P.
2 Open and close any of the doors.
3 Restart the engine.
●Unlocking the doors using the
smart key system may not be pos-
sible immediately after reconnect-
ing the battery. If this happens,
use the wireless remote control or
the mechanical key to lock/unlock
the doors.
●Start the engine with the engine
switch in ACC. T he engine may
not start with th e engine switch
turned off. However, the engine
will operate normally from the sec-
ond attempt.
●The engine switch mode is
recorded by the vehicle. If the bat-
tery is disconnected and recon-
nected, the vehicle will return the
engine switch mode to the status it
was in before the battery was dis-
connected. Make sure to turn off
the engine before disconnecting
the battery. Take extra care when
connecting the battery if the
engine switch mode prior to the
battery being disconnected is
unknown.
If the system will not start even after
multiple attempts, contact your Toy-
WARNING
■When filling the reservoir
Take care as brake fluid can harm
your hands and eyes and damage
painted surfaces.
If fluid gets on your hands or in
your eyes, flush t he affected area
with clean water immediately.
If you still experien ce discomfort,
see a doctor.
NOTICE
■If the fluid level is low or high
It is normal for the brake fluid level
to go down slightly as the brake
pads wear out or when the fluid
level in the accumulator is high.
If the reservoir needs frequent
refilling, there may be a serious
problem.
Battery

3926-3. Do-it-yourself maintenance
ota dealer.
If any washer does not work or
the warning message appears
on the multi-information display,
the washer tank may be empty.
Add washer fluid.
WARNING
■Chemicals in the battery
Batteries contai n 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 precau-
tions while working on or near the
battery:
●Do not cause sparks by touch-
ing the battery terminals with
tools.
●Do not smoke or light a match
near the battery.
●Avoid contact with eyes, skin
and clothes.
●Never inhale or swallow electro-
lyte.
●Wear protective safety glasses
when working near the battery.
●Keep children away from the
battery.
■Where to safely charge the
battery
Always charge the battery in an
open area. Do not charge the bat-
tery in a garage or closed room
where there is insufficient ventila-
tion.
■How to recharge the battery
Only perform a slow charge (5 A
or less). The 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 feel 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.
NOTICE
■When recharging the battery
Never recharge the battery while
the engine is running. Also, be
sure all accessories are turned
off.
Washer fluid

4106-3. Do-it-yourself maintenance
■If the electronic 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.
 Flathead screwdriver
 Small flathead screwdriver
 Lithium battery CR2032
■Use a CR2032 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.
To prevent damage to the key,
cover the tip of the flathead screw-
driver with a rag.
3Remove the depleted battery.
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.
You will need the follow-
ing items:
Replacing the battery

4116-3. Do-it-yourself maintenance
6
Maintenance and care
minal facing up.
WARNING
■Battery precautions
Observe the following precau-
tions. Failure to do so may 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 b attery into a
part of your body, 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
■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.