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PRIUS v_OM_OM47B23U_(U)
4437-3. Do-it-yourself maintenance
7
Maintenance and care
Make sure that the 12-volt 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 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.
■ After recharging/reconnecting 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.
● Restart the hybrid system, depress the brake pedal, and confirm that it is
possible to shift into each shift position.
If the system will not start even after multiple attempts at all methods above,
contact your Toyota dealer.
Exterior
1
2
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PRIUS v_OM_OM47B23U_(U)
7-3. Do-it-yourself maintenance
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 (4.2 A or less). The 12-volt 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.
■ When replacing the 12-volt battery
Use a 12-volt battery designed for this vehicle. Failure to do so may cause
gas (hydrogen) to enter the passenger compartment, causing a fire or
explosion.
For replacement of the 12-volt battery, contact your Toyota dealer.
Page 445 of 624
PRIUS v_OM_OM47B23U_(U)
4457-3. Do-it-yourself maintenance
7
Maintenance and care
WARNING
■When disconnecting th e 12-volt battery
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.
Do not disconnect the negative (-) termi-
nal on the body side as shown. The dis-
connected negative (-) terminal may
touch the positive (+) terminal, which
may cause a short and result in death or
serious injury.
Page 464 of 624
464
PRIUS v_OM_OM47B23U_(U)
7-3. Do-it-yourself maintenance
Electronic key batter y
●Flathead screwdriver
● Lithium battery CR2032
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.
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.
Insert a new battery with the “+”
terminal facing up.
When installing, reverse the steps listed.
Replace the battery with a new one if it is depleted.
You will need the following items:
Replacing the battery
1
2
3
4
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PRIUS v_OM_OM47B23U_(U)
4657-3. Do-it-yourself maintenance
7
Maintenance and care
■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.
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.
Page 483 of 624
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PRIUS v_OM_OM47B23U_(U)
8When trouble arises
8-1. Essential informationEmergency flashers .......... 484
If your vehicle has to be stopped in an
emergency ...................... 485
8-2. Steps to take in an emergency
If your vehicle needs to be towed ......................... 486
If you think something is wrong .............................. 491
If a warning light turns on or a warning buzzer
sounds ............................ 492
If a warning message is displayed ......................... 506
If you have a flat tire.......... 524
If the hybrid system will not start ........................... 537
If the electronic key does not operate properly........ 539
If the 12-volt battery is discharged ...................... 541
If your vehicle overheats ... 546
If the vehicle becomes stuck ............................... 551
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PRIUS v_OM_OM47B23U_(U)
8-2. Steps to take in an emergency
If your vehicle needs to be towed
In the following situations, it is not possible to be towed by another
vehicle using cables or chains, as the front wheels may be locked due
to the parking lock. Contact your Toyota dealer or commercial towing
service.
●There is a malfunction in the shift control system. ( P. 494, 508)
● There is a malfunction in the immobilizer system. ( P. 83)
● There is a malfunction in the smart key system. ( P. 539)
● The 12-volt battery is discharged. ( P. 541)
The following may indicate a problem with your hybrid transmission.
Contact your Toyota dealer or commercial towing service before tow-
ing.
● The hybrid system warning light turns on or the hybrid system
warning message is displayed on the multi-information display and
the vehicle does not move.
● The vehicle makes an abnormal sound.
Do not tow with a sling-type truck
to prevent body damage.
If towing is necessary, we re commend having your vehicle
towed by your Toyota dealer or commercial towing service,
using a wheel-lift type tr uck or flat bed truck.
Use a safety chain system for all towing, and abide by all state/
provincial and local laws.
Situations when it is not possibl e to be towed by another vehicle
Situations when it is necessary to contact dealers before towing
Towing with a sling-type truck
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4958-2. Steps to take in an emergency
PRIUS v_OM_OM47B23U_(U)
8
When trouble arises
(Flashes)
(If equipped)
P position request indicator light (warning buzzer)
The amount of charge remaining in the hybrid battery
(traction battery) has fallen because the shift position has
been left in N for a long time
Because recharging is not possible when the shift
position is in N, shift the shift position to P when
parking the vehicle for a long time.
• The driver’s door has been opened while the shift posi- tion is in N, D or B
• An attempt has been made to start the hybrid system while the shift position is in anything other than P
Shift the shift position to P.
(If equipped)
Hybrid system overheat warn ing light (warning buzzer)
The hybrid system has overheated
This light may come on when driving under severe operat-
ing conditions, and the output of the hybrid system may
temporarily decrease in order to protect the system. (For
example, when driving up a long steep hill or driving up a
steep hill in reverse.)
Stop and check. ( P. 546)
(If equipped)
Cruise control indicator (yellow indicator)
Indicates a malfunction in the cruise control
Have the vehicle inspected by your Toyota dealer
immediately.
(Only outer frame
flashes)
(If equipped)
Low hybrid battery (tract ion battery) warning light
(warning buzzer)
Hybrid battery (traction battery) level becomes low
because the shift position is in N for long time
Because recharging is not possible when the shift
position is in N, shift the shift position to P when
parking the vehicle for a long time.
High coolant temperat ure warning light
Changes from a flashing to a solid light when the engine
coolant temperature increases
Immediately stop the vehicle in a safe place. ( P. 546)
(If equipped)
Automatic headlight leveling system warning light
Indicates a malfunction in the automatic headlight leveling
system
Have the vehicle inspected by your Toyota dealer
immediately.
Open door warning light (warning buzzer)*2
Indicates that a door is not fully closed
Check that all the doors are closed.
Warning lightWarning light/Details/Actions