Page 508 of 716
5087-3. Do-it-yourself maintenance
HIGHLANDER_U (OM48F09U)■
2.7 L 4-cylinder (1AR-FE) engine
Engine compartment
Washer fluid tank
( P. 519)
Fuse boxes ( P. 541)
Engine oil level dipstick ( P. 510)
Engine oil filler cap ( P. 511)
Engine coolant reservoir ( P. 513) Battery
( P. 516)
Brake fluid reservoir ( P. 515)
Electric cooling fans
Condenser ( P. 514)
Radiator ( P. 514)1
2
3
4
5
6
7
8
9
10
Page 509 of 716
5097-3. Do-it-yourself maintenance
7
Maintenance and care
HIGHLANDER_U (OM48F09U)■
3.5 L V6 (2GR-FE) engine
Washer fluid tank
( P. 519)
Fuse boxes ( P. 541)
Engine oil filler cap ( P. 511)
Engine oil level dipstick ( P. 510)
Engine coolant reservoir ( P. 513) Battery
( P. 516)
Brake fluid reservoir ( P. 515)
Electric cooling fans
Condenser ( P. 514)
Radiator ( P. 514)1
2
3
4
5
6
7
8
9
10
Page 516 of 716
5167-3. Do-it-yourself maintenance
HIGHLANDER_U (OM48F09U)
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 sure to disconnect
the ground cable.
● Make sure the power switch on the charger is off when connecting and dis-
connecting the charger cables to the battery.
Battery
1
2
Page 517 of 716

5177-3. Do-it-yourself maintenance
7
Maintenance and care
HIGHLANDER_U (OM48F09U)■
After recharging/reconnecting the ba ttery (vehicles with a smart key sys-
tem)
The engine may not start. Follow the procedure below to initialize 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 possible 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 with the engine switch turned off. However, the engine will
operate normally from the second attempt.
● The engine switch mode is recorded by the vehicle. If the battery is discon-
nected and reconnected, the vehicle will return the engine switch mode to
the status it was in before the battery was disconnected. Make sure to turn
off the engine before disconnecting the battery. Take extra care when con-
necting the battery if the engine switch mode prior to the battery being dis-
connected 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 risk 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 tools.
● 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.
1
2
3
Page 518 of 716

5187-3. Do-it-yourself maintenance
HIGHLANDER_U (OM48F09U)
WARNING
■Where to safely charge the battery
Always charge the battery in an open area. Do not charge the battery 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 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.
NOTICE
■When recharging the battery
Never recharge the battery while the engine is operating. Also, be sure all
accessories are turned off.
Page 538 of 716
5387-3. Do-it-yourself maintenance
HIGHLANDER_U (OM48F09U)
●Flathead screwdriver
● Small flathead screwdriver
● Lithium battery CR2016 (vehicles without a smart key system), or
CR2032 (vehicles with a smart key system)
Vehicles without a smart key system
Remove the cover.
To prevent damage to the key,
cover the tip of the flathead screw-
driver with a rag.
To prevent the buttons from being
disassembled, face the button sur-
face downward.
Remove the module.
Wireless remote control/electronic key
batter y
Replace the battery with a new one if it is depleted.
You will need the following items:
Replacing the battery
1
2
Page 539 of 716
5397-3. Do-it-yourself maintenance
7
Maintenance and care
HIGHLANDER_U (OM48F09U)
Open the case cover using a
coin protected with tape etc.
and remove the depleted bat-
tery using a small flathead
screwdriver.
Insert a new battery with the “+”
terminal facing up.
Vehicles with a smart key system
Take out the mechanical key.
Remove the cover.
To prevent damage to the key,
cover the tip of the flathead screw-
driver with a rag.
Remove the depleted battery.
Insert a new battery with the “+”
terminal facing up.
3
1
2
3
Page 540 of 716

5407-3. Do-it-yourself maintenance
HIGHLANDER_U (OM48F09U)
■Use a CR2016 (vehicles without a sm art key system) or CR2032 (vehicles
with a smart key system) 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 manu-
facturer.
● Dispose of used batteries according to local laws.
■ If the key battery is depleted
The following symptoms may occur:
●The smart key system (if equipped) and wireless remote control will not
function properly.
● The operational range will be reduced.
WARNING
■ Removed battery and other parts
These parts are small and if swallowed by a child, they can cause choking.
Keep away from children. Failure to do so could result in death or serious
injury.
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.