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PRIUS PRIME_OM_OM47A88U_(U)
5757-3. Do-it-yourself maintenance
7
Maintenance and care
Tire inflation
pressure
(→ P. 603)• Tire pressure gauge
• Compressed air source
Washer fluid
(→ P. 592)• Water or washer fluid containing antifreeze (for win-
ter 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
● Make sure that the “Accessory”, “Ignition ON” or mileage display
(→P. 197) on the main display and the “READY” indicator are both off.
● Keep hands, clothing and tools away from the moving fan.
● Be careful not to touch the engine, power control unit, radiator, exhaust
manifold, etc. right after 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 compartment.
● Do not smoke, cause sparks or expose an open flame to fuel. Fuel fumes
are flammable.
● Be extremely cautious when working on the 12- volt battery. It contains
poisonous and corrosive sulfuric acid.
■ When working near the electric cooling fans or radiator grille
Be sure the power switch is off.
With the power switch in ON mode, t he electric cooling fans may automati-
cally start to run if the air condition ing is on and/or the coolant temperature
is high. ( →P. 586)
■ Safety glasses
Wear safety glasses to prevent flying or falling material, fluid spray, etc.
from getting in your eyes.
ItemsParts and tools
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7-3. Do-it-yourself maintenance
Engine compartment
Engine coolant reservoir (→ P. 584)
Fuse boxes ( →P. 630)
Engine oil level dipstick (→ P. 581)
Engine oil filler cap ( →P. 582)
Brake fluid reservoir (→ P. 590) Washer fluid tank (
→P. 592)
12-volt battery ( →P. 587)
Power control unit coolant
reservoir ( →P. 584)
Radiator ( →P. 586)
Condenser ( →P. 586)
Electric cooling fans1
2
3
4
5
6
7
8
9
10
11
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PRIUS PRIME_OM_OM47A88U_(U)
5877-3. Do-it-yourself maintenance
7
Maintenance and care
Check the 12-volt battery as follows:
■12-volt battery exterior
Make sure that the 12-volt battery terminals are not corroded and
that there are no loose connections, cracks, or loose clamps.
Terminals
■ When opening the cover of th e positive (+) battery terminal
■ Before recharging
When recharging, the 12-volt battery produces hydrogen gas which is flam-
mable and explosive. Therefore, observe the following precautions before
recharging:
●If recharging with the 12-volt battery installed on the vehicle, be sure to dis-
connect the ground cable.
● Make sure the power switch on the charger is off when connecting and dis-
connecting the charger cables to the 12-volt battery.
12-volt battery
While pushing the portion shown in the
illustration from both sides, lift the end of
the cover up.
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PRIUS PRIME_OM_OM47A88U_(U)
7-3. Do-it-yourself maintenance
■After recharging/reconnect ing the 12-volt battery
● Unlocking the doors using the smart key system may not be possible imme-
diately after reconnecting the 12-volt battery. If this happens, use the wire-
less remote control or the mechanical key to lock/unlock the doors.
● Start the hybrid system with the power switch in ACCESSORY mode. The
hybrid system may not start with the power switch turned off. However, the
hybrid system will operate normally from the second attempt.
● The power switch mode is recorded by the vehicle. If the 12-volt battery is
reconnected, the vehicle will return the power switch mode to the status it
was in before the 12-volt battery was disconnected. Make sure to turn off
the power before disconnect the 12-volt battery. Take extra care when con-
necting the 12-volt battery if the power switch mode prior to discharge is
unknown.
If the system will not start even after multiple attempts at all methods above,
contact your Toyota dealer.
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 th e 12-volt battery
Only perform a slow charge (5 A or less). The 12-volt battery may explode if
charged at a quicker rate.
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PRIUS PRIME_OM_OM47A88U_(U)
5897-3. Do-it-yourself maintenance
7
Maintenance and care
WARNING
■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 th e 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.
NOTICE
■ When recharging the 12-volt battery
Never recharge the 12-volt battery while the hybrid system is operating.
Also, be sure all accessories are turned off.
Page 622 of 784
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7-3. Do-it-yourself maintenance
■Checking interval
Inspect and replace the air conditioning filter according to the maintenance
schedule. In dusty areas or areas with heavy traffic flow, early replacement
may be required. (For scheduled maintenance information, please refer to the
“Scheduled Maintenance Guide” or “Owner’s Manual Supplement”.)
■ If air flow from the vents decreases dramatically
The filter may be clogged. Check the filter and replace if necessary.
WARNING
■When replacing the air conditioning filter
Observe the following precautions. Failure to do so may result in the air
conditioning system operating during the procedure, possibly resulting in
injury.
● Check that the charging connector is not connected
The air conditioning may operate due to the “Climate Prep” (→P. 147) or
“Traction Battery Cooler” (→P. 127) setting.
● Do not use the Remote Air Conditioning System
Page 627 of 784
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PRIUS PRIME_OM_OM47A88U_(U)
7-3. Do-it-yourself maintenance
7
Maintenance and care
Electronic key batter y
●Flathead screwdriver
● Lithium battery CR2032
Release the lock and take out
the mechanical key.
Remove the cover.
Use a screwdriver of an appropri-
ate size. Forcedly prying may
cause the cover damaged.
To prevent damage to the key,
cover the tip of the screwdriver with
a rag.
Replace the battery with a new one if it is depleted.
You will need the following items:
Replacing the battery
1
2
Page 628 of 784
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PRIUS PRIME_OM_OM47A88U_(U)
7-3. Do-it-yourself maintenance
Remove the depleted battery.
When removing the cover, if the
battery cannot be seen due to the
electronic key module attaching to
the upper cover, remove the elec-
tronic key module from the cover
so that the battery is visible as
shown in the illustration.
When removing the battery, use a
screwdriver of an appropriate size.
Insert a new battery with the “+” terminal facing up.
When installing, reverse the steps listed.
■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 manu-
facturer.
● Dispose of used batteries according to the local laws.
■ If the electronic key battery is depleted
The following symptoms may occur:
●The smart key system and wireless remote control will not function properly.
● The operational range will be reduced.
3
4