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PRIUS PRIME_OM_OM47D13U_(U)
5937-3. 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 connecti ons, cracks, or loose clamps.
Terminals
■ When opening the cover of the positive (+) battery terminal
■ Before recharging
When recharging, the 12-volt battery produces hydrogen gas which is flam-
mable and explosive. Therefore, observe the following precautio ns 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 connectin g 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_OM47D13U_(U)
7-3. Do-it-yourself maintenance
■After recharging/reconnecting the 12-volt battery
●Unlocking the doors using the smart key system may not be possi ble 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 do ors.
● 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-vol t battery is
reconnected, the vehicle will return the power switch mode to t he status it
was in before the 12-volt battery was disconnected. Make sure t o turn off
the power before disconnect the 12-volt battery. Take extra car e when con-
necting the 12-volt battery if the power switch mode prior to d ischarge is
unknown.
If the system will not start even after multiple attempts at al l methods above,
contact your Toyota dealer.
WARNING
■ Chemicals in the 12-volt battery
The 12-volt battery contains poisonous and corrosive sulfuric a cid 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 w ith 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 ba ttery.
● 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 charg e the
12-volt battery in a garage or closed room where there is insufficient ventila-
tion.
■ How to recharge the 12-volt battery
Only perform a slow charge (5 A or less). The 12-volt battery m ay explode if
charged at a quicker rate.
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PRIUS PRIME_OM_OM47D13U_(U)
5957-3. 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 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.
■ When disconnecting the 12-volt battery
Do not disconnect the negative (-) terminal on the body side. T he discon-
nected negative (-) terminal may touch the positive (+) termina l, which may
cause a short and result in death or serious injury.
NOTICE
■ When recharging th e 12-volt battery
Never recharge the 12-volt battery while the hybrid system is o perating.
Also, be sure all accessories are turned off.
Page 628 of 792
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PRIUS PRIME_OM_OM47D13U_(U)
7-3. Do-it-yourself maintenance
■Checking interval
Inspect and replace the air conditioning filter according to th e maintenance
schedule. In dusty areas or areas with heavy traffic flow, earl y 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 ven ts decreases dramatically
The filter may be clogged. Check the filter and replace if nece ssary.
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 re sulting in
injury.
● Check that the charging connector is not connected
The air conditioning may operate due to the “Climate Prep” (P. 154) or
“Traction Battery Cooler” (P. 133) setting.
● Do not use the Remote Air Conditioning System
Page 633 of 792
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PRIUS PRIME_OM_OM47D13U_(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 n ew one if it is depleted.
You will need the following items:
Replacing the battery
1
2
Page 634 of 792
634
PRIUS PRIME_OM_OM47D13U_(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 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 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 funct ion properly.
● The operational range will be reduced.
3
4
Page 635 of 792
PRIUS PRIME_OM_OM47D13U_(U)
6357-3. Do-it-yourself maintenance
7
Maintenance and care
WARNING
■Removed battery a nd 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 cont rol.
● Do not bend either of the battery terminals.
Page 649 of 792
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PRIUS PRIME_OM_OM47D13U_(U)
8When trouble arises
8-1. Essential informationEmergency flashers .......... 650
If your vehicle has to be stopped in an
emergency ...................... 651
If the vehicle is trapped in rising water.................. 652
8-2. Steps to take in an emergency
If your vehicle needs to be towed ......................... 653
If you think something is wrong .............................. 659
If a warning light turns on or a warning buzzer
sounds ............................ 660
If a warning message is displayed......................... 670
If you have a flat tire.......... 678
If the hybrid system will not start ........................... 695
If the electronic key does not operate properly ........ 697
If the 12-volt battery is discharged ...................... 701
If your vehicle overheats ... 707
If the vehicle becomes stuck ............................... 712