2021 TOYOTA 4RUNNER battery

4176-3. Do-it-yourself maintenance
6
Maintenance and care
4RUNNER (U)
Check the battery as follows.
■Battery exterior
Make sure that the battery terminals are not corroded and that
there are no loose connections, cracks, or loose clamps.
Terminals
Hold-down clamp
■ Before recharging
When recharging, the battery produces hydrogen gas which is flammable and
explosive. Therefore, observe the following before recharging:
●If recharging with the battery installed on the vehicle, be sur e to disconnect
the ground cable.
● Make sure the power switch on the charger is off when connectin g and dis-
connecting the charger cables to the battery.
WARNING
■ When checking the reservoir
Take care as the reservoir may be hot.
NOTICE
■When adding fluid
Avoid overfilling, or the power steering may be damaged.
■ After replacing the reservoir cap
Check the steering box case, vane pump and hose connections for leaks or
damage.
Battery
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4186-3. Do-it-yourself maintenance
4RUNNER (U)■
After recharging/reconnecting the battery (vehicles with a smar t key sys-
tem)
The engine may not start. Follow the procedure below to initial ize the system.
Shift the shift lever to P.
Open and close any of the doors.
Restart the engine.
● Unlocking the doors using the smart key system may not be possi ble imme-
diately after reconnecting 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 ACCESSORY mode. The engine
may not start when the engine switch turned from off. However, the engine
will operate normally from the second attempt.
● The engine switch mode is recorded by the vehicle. If the batte ry is recon-
nected, the vehicle will return the engine switch mode to the s tatus it was in
before the battery was disconnected. Make sure to turn off the engine
before disconnect the battery. Take extra care when connecting the battery
if the engine switch mode prior to discharge is unknown.
If the system will not start even after multiple attempts, contact your Toyota
dealer.
WARNING
■ Chemicals in the battery
Batteries contain poisonous and corrosive sulfuric acid and may produce
hydrogen gas which is flammable and explosive. To reduce the ri sk of death
or serious injury, take the following precautions while working on or near the
battery:
● Do not cause sparks by touching the battery terminals with tool s.
● Do not smoke or light a match near the battery.
● Avoid contact with eyes, skin and clothes.
● Never inhale or swallow electrolyte.
● Wear protective safety glasses when working near the battery.
● Keep children away from the battery.
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4196-3. Do-it-yourself maintenance
6
Maintenance and care
4RUNNER (U)
WARNING
■Where to safely charge the battery
Always charge the battery in an open area. Do not charge the ba ttery in a
garage or closed room where there is insufficient ventilation.
■ How to recharge the battery
Only perform a slow charge (5 A or less). The battery may explo de 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 ge t immedi-
ate medical attention. If possible, continue to apply water wit h 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.
NOTICE
■When recharging the battery
Never recharge the battery while the engine is running. Also, b e sure all
accessories are turned off.

4436-3. Do-it-yourself maintenance
6
Maintenance and care
4RUNNER (U)
●Flathead screwdriver
● Small flathead screwdriver
● Lithium battery CR2016 (vehicles without a smart key system), o r
CR1632 (vehicles with a smart key system)
Remove the cover.
To prevent damage to the key,
cover the tip of the screwdriver with
a rag.
Remove the module.
Open the case cover using a
coin protected with tape etc.
and remove the depleted bat-
tery.
Insert a new battery with the “+”
terminal facing up.
Wireless remote control/electronic key
batter y
Replace the battery with a n ew one if it is depleted.
You will need the following items:
Replacing the battery (vehicles without a smart key system)
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4446-3. Do-it-yourself maintenance
4RUNNER (U)
Take out the mechanical key.
Remove the cover.
To prevent damage to the key,
cover the tip of the screwdriver with
a rag.
Remove the depleted battery.
Insert a new battery with the “+”
terminal facing up.
■Use a CR2016 (vehicles without a smart key system) or CR1632 (v ehicles
with a smart key system) lithium battery
● Batteries can be purchased at your Toyota dealer, local electri cal appliance
shops or camera stores.
● Replace only with the same or equivalent type recommended by the manu-
facturer.
● Dispose of used batteries according to local laws.
■ If the electronic key battery is depleted
The following symptoms may occur:
●The smart key system and wireless remote control will not funct ion properly.
● The operational range will be reduced.
Replacing the battery (vehic les with a smart key system)
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4456-3. Do-it-yourself maintenance
6
Maintenance and care
4RUNNER (U)
WARNING
■Battery precautions
Observe the following precautions.
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 or button battery is used in the wireless remote control/elec-
tronic key. If a battery is swallowed, it may cause severe chem ical 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 wireless r emote con-
trol/electronic key and stow the key in the place where childre n cannot
reach, and then contact your Toyota dealer.
● If you accidentally swallow a battery or put a battery into a p art of your
body, get emergency medical attention immediately.
■ To prevent battery explosion or leakage of flammable liquid or gas
● Replace the battery with a new battery of the same type. If a w rong type of
battery is used, it may explode.
● Do not expose batteries to extremely low pressure due to high altitude or
extremely high temperatures.
● Do not burn, break or cut a battery.
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 cont rol.
● Do not bend either of the battery terminals.

461
When trouble arises7
4RUNNER (U)7-1. Essential information
Emergency flashers .......... 462
If your vehicle has to be stopped in an
emergency ...................... 463
If the vehicle is trapped in rising water ..................... 465
7-2. Steps to take in an emergency
If your vehicle needs to be towed .............................. 466
If you think something is wrong .............................. 472
Fuel pump shut off system ............................ 473
If a warning light turns on or a warning buzzer
sounds ............................ 474
If a warning message is displayed......................... 484
If you have a flat tire.......... 489
If the engine will not start ................................. 504
If you cannot operate back door opener ............ 506
If the electronic key does not operate properly
(vehicles with a smart
key system)..................... 507
If the vehicle battery is discharged ...................... 510
If your vehicle overheats ........................ 514
If the vehicle becomes stuck ............................... 517

462
4RUNNER (U)
7-1. Essential information
Press the switch.
All the turn signals will flash.
To turn them off, press the switch
once again.
■Emergency flashers
If the emergency flashers are used for a long time while the en gine is not
operating, the battery may discharge.
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.