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3296-3. Do-it-yourself maintenance
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6
Maintenance and care
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 the 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.
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3306-3. Do-it-yourself maintenance
PRIUS +_OM_OM47888E_(EE)
WARNING
■ 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 any authorized Toyota dealer
or repairer, or another duly qualified and equipped professional.
■ When disconnecting the 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.
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3316-3. Do-it-yourself maintenance
PRIUS +_OM_OM47888E_(EE)
6
Maintenance and care
Tires
New tread
Treadwear indicator
Worn tread
The location of treadwear indica-
tors is shown by the “TWI” or “∆”
marks, etc., molded on the sidewall
of each tire.
Check spare tire condition and
pressure if not rotated.
Rotate the tires in the order
shown.
To equalize tire wear and help
extend tire life, Toyota recom-
mends that tire rotation is carried
out approximately every 10000 km
(6000 miles).
Do not fail to initialize the tire pres-
sure warning system after tire rota-
tion.
Replace or rotate tires in accordance with maintenance sched-
ules and treadwear.
Checking tires
1
2
3
Tire rotation
Front
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3326-3. Do-it-yourself maintenance
PRIUS +_OM_OM47888E_(EE)
Your vehicle is equipped with a tire pressure warning system that uses
tire pressure warning valves and transmitters to detect low tire infla-
tion pressure before serious problems arise.
If the tire pressure drops below a predetermined level, the driver is
warned by a warning light. (→P. 381)
The compact spare tire is not equipped with a tire pressure warning
valve and transmitter.
◆Installing tire pressure warning valves and transmitters
When replacing tires or wheels, tire pressure warning valves and
transmitters must also be installed.
When new tire pressure warning valves and transmitters are
installed, new ID codes must be registered in the tire pressure
warning computer and the tire pressure warning system must be
initialized. Have tire pressure warning valve and transmitter ID
codes registered by any authorized Toyota dealer or repairer, or
another duly qualified and equipped professional. ( →P. 333)
◆Initializing the tire pressure warning system
■The tire pressure warning system must be initialized in the fol-
lowing circumstances:
● When rotating front and rear tires which have different tire infla-
tion pressures
● When changing the tire size
When the tire pressure warning system is initialized, the current tire
inflation pressure is set as the benchmark pressure.
Tire pressure warning system
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3336-3. Do-it-yourself maintenance
PRIUS +_OM_OM47888E_(EE)
6
Maintenance and care
■How to initialize the tire pressure warning systemPark the vehicle in a safe place and turn the power switch off.
Initialization cannot be performed while the vehicle is moving.
Adjust the tire inflation pressure to the specified cold tire inflation
pressure level. ( →P. 461)
Make sure to adjust the tire pressure to the specified cold tire inflation
pressure level. The tire pressure warning system will operate based on
this pressure level.
Turn the power switch to ON mode.
Press and hold the tire pres-
sure warning reset switch
until the tire pressure warn-
ing light blinks slowly 3 times.
Wait for a few minutes with the power switch in ON mode and
then turn the power switch off.
◆Registering ID codes
The tire pressure warning valve and transmitter is equipped with a
unique ID code. When replacing a tire pressure warning valve and
transmitter, it is necessary to register the ID code. Have the ID code
registered by any authorized Toyota dealer or repairer, or another
duly qualified and equipped professional.
1
2
3
4
5
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3346-3. Do-it-yourself maintenance
PRIUS +_OM_OM47888E_(EE)
■When to replace your vehicle’s tires
Tires should be replaced if:
●You have tire damage such as cuts, splits, cracks deep enough to expose
the fabric, and bulges indicating internal damage.
● A tire goes flat repeatedly or cannot be properly repaired due to the size or
location of a cut or other damage.
If you are not sure, consult with any authorized Toyota dealer or repairer, or
another duly qualified and equipped professional.
■ Replacing tires and wheels
If the ID code of the tire pressure warning valve and transmitter is not regis-
tered, the tire pressure warning system will not work properly. After driving for
about 10 minutes, the tire pressure warning light blinks for 1 minute and stays
on to indicate a system malfunction.
■ Tire life
Any tire over 6 years old must be checked by a qualified technician even if it
has seldom or never been used or damage is not obvious.
■ Routine tire inflation pressure checks
The tire pressure warning system does not replace routine tire inflation pres-
sure checks. Make sure to check tire inflation pressure as part of your routine
of daily vehicle checks.
■ If the tread on snow tires wears down below 4 mm (0.16 in.)
The effectiveness of the tires as snow tires is lost.
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3356-3. Do-it-yourself maintenance
PRIUS +_OM_OM47888E_(EE)
6
Maintenance and care
■Situations in which the tire pressure warning system may not operate
properly
●In the following cases, the tire pressure warning system may not operate
properly.
• If non-genuine Toyota wheels are used.
• When a replacement tire is used, the system may not operate correctly
due to the structure of the replacement tire.
• A tire has been replaced with a tire that is not of the specified size.
• Tire chains etc. are equipped.
• An auxiliary-supported run-flat tire is equipped.
• If a window tint that affects the radio wave signals is installed.
• If there is a lot of snow or ice on the vehicle, particularly around the
wheels or wheel housings.
• If the tire inflation pressure is extremely higher than the specified level.
• If wheel without the tire pressure warning valve and transmitter is used.
• If the ID code on the tire pressure warning valves and transmitters is not registered in the tire pressure warning computer.
● Performance may be affected in the following situations.
• Near a TV tower, electric power plant, gas station, radio station, large dis-
play, airport or other facility that generates strong radio waves or electri-
cal noise
• When carrying a portable radio, cellular phone, cordless phone or other wireless communication device
● When the vehicle is parked, the time taken for the warning to start or go off
could be extended.
● When tire inflation pressure declines rapidly for example when a tire has
burst, the warning may not function.
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3366-3. Do-it-yourself maintenance
PRIUS +_OM_OM47888E_(EE)■
The initialization operation
●Make sure to carry out initialization after adjusting the tire inflation pressure.
Also, make sure the tires are cold before carrying out initialization or tire
inflation pressure adjustment.
● If you have accidentally turned the power switch off during initialization, it is
not necessary to press the reset switch again as initialization will restart
automatically when the power switch has been turned to ON mode for the
next time.
● If you accidentally press the reset switch when initialization is not necessary,
adjust the tire inflation pressure to the specified level when the tires are
cold, and conduct initialization again.
■ Warning performance of the tire pressure warning system
The warning of the tire pressure warning system will change in accordance
with the conditions under which it was initialized. For this reason, the system
may give a warning even if the tire pressure does not reach a low enough
level, or if the pressure is higher than the pressure that was adjusted to when
the system was initialized.
■ When initialization of the tire pressure warning system has failed
Initialization can be completed in a few minutes. However, in the following
cases, the settings have not been recorded and the system will not operate
properly. If repeated attempts to record tire inflation pressure settings are
unsuccessful, have the vehicle inspected by any authorized Toyota dealer or
repairer, or another duly qualified and equipped professional.
● When operating the tire pressure warning reset switch, the tire pressure
warning light does not blink 3 times.
● After carrying out the initialization procedure, the tire pressure warning light
blinks for 1 minute then stays on after driving for 20 minutes.