Page 433 of 624

PRIUS v_OM_OM47B23U_(U)
4337-3. Do-it-yourself maintenance
7
Maintenance and care
WARNING
■Used engine oil
●Used engine oil contains potentially harmful contaminants which may
cause skin disorders such as inflammation and skin cancer, so care
should be taken to avoid prolonged and repeated contact. To remove used
engine oil from your skin, wash thoroughly with soap and water.
● Dispose of used oil and filters only in a safe and acceptable manner. Do
not dispose of used oil and filters in household trash, in sewers or onto the
ground. Call your Toyota dealer, service station or auto parts store for
information concerning recycling or disposal.
● Do not leave used engine oil within the reach of children.
NOTICE
■To prevent serious engine damage
Check the oil level on a regular basis.
■ When replacing the engine oil
●Be careful not to spill engine oil on the vehicle components.
● Avoid overfilling, or the engine could be damaged.
● Check the oil level on the dipstick every time you refill the vehicle.
● Be sure the engine oil filler cap is properly tightened.
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PRIUS v_OM_OM47B23U_(U)
4357-3. Do-it-yourself maintenance
7
Maintenance and care
■Coolant selection
Only use “Toyota Super Long Life Coolant” or a similar high quality ethylene
glycol based non-silicate, non-amine, non-nitrite, and non-borate coolant with
long-life hybrid organic acid technology.
U.S.A.:
“Toyota Super Long Life Coolant” is a mixture of 50% coolant and 50% deion-
ized water. (Minimum temperature: -31 F [-35 C])
Canada:
“Toyota Super Long Life Coolant” is a mixture of 55% coolant and 45% deion-
ized water. (Minimum temperature: -44 F [-42 C])
For more details about coolant, contact your Toyota dealer.
■ If the coolant level drops within a short time of replenishing
Visually check the radiator, hoses, engine/power control unit coolant reservoir
caps, drain cock and water pump.
If you cannot find a leak, have your Toyota dealer test the cap and check for
leaks in the cooling system.
WARNING
■When the hybrid system is hot
Do not remove the engine/power control unit coolant reservoir caps.
The cooling system may be under pressure and may spray hot coolant if the
cap is removed, causing serious injuries, such as burns.
NOTICE
■When adding coolant
Coolant is neither plain water nor straight antifreeze. The correct mixture of
water and antifreeze must be used to provide proper lubrication, corrosion
protection and cooling. Be sure to read the antifreeze or coolant label.
■ If you spill coolant
Be sure to wash it off with water to prevent it from damaging parts or paint.
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444
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 453 of 624

PRIUS v_OM_OM47B23U_(U)
4537-3. Do-it-yourself maintenance
7
Maintenance and care
WARNING
■When inspecting or replacing tires
Observe the following precautions to prevent accidents.
Failure to do so may cause damage to parts of the drive train as well as
dangerous handling characteristics, which may lead to an accident resulting
in death or serious injury.
●Do not mix tires of different makes, models or tread patterns.
Also, do not mix tires of remarkably different treadwear.
● Do not use tire sizes other than those recommended by Toyota.
● Do not mix differently constructed tires (radial, bias-belted or bias-ply
tires).
● Do not mix summer, all season and snow tires.
● Do not use tires that have been used on another vehicle.
Do not use tires if you do not know how they were used previously.
■ When initializing the tire pressure warning system
Do not operate the tire pressure warning reset switch without first adjusting
the tire inflation pressure to the specified level. Otherwise, the tire pressure
warning light may not come on even if the tire inflation pressure is low, or it
may come on when the tire inflation pressure is actually normal.
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PRIUS v_OM_OM47B23U_(U)
7-3. Do-it-yourself maintenance
Wheels
When replacing wheels, care should be taken to ensure that they are
equivalent to those removed in load capacity, diameter, rim width and
inset
*.
Replacement wheels are available at your Toyota dealer.
*: Conventionally referred to as “offset”.
Toyota does not recommend using the following:
● Wheels of different sizes or types
● Used wheels
● Bent wheels that have been straightened
● Use only Toyota wheel nuts and wrenches designed for use with
your aluminum wheels.
● When rotating, repairing or changi ng your tires, check that the
wheel nuts are still tight after driving 1000 miles (1600 km).
● Be careful not to damage the aluminum wheels when using tire
chains.
● Use only Toyota genuine balance weights or equivalent and a plas-
tic or rubber hammer when balancing your wheels.
■When replacing wheels
The wheels of your vehicle are equipped with tire pressure warning
valves and transmitters that allow the tire pressure warning system to
provide advance warning in the event of a loss in tire inflation pressure.
Whenever wheels are replaced, tire pressure warning valves and trans-
mitters must be installed. ( P. 447)
If a wheel is bent, cracked or heavily corroded, it should be
replaced. Otherwise, the tire may separate from the wheel or
cause a loss of handling control.
Wheel selection
Aluminum wheel precautions
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PRIUS v_OM_OM47B23U_(U)
4597-3. Do-it-yourself maintenance
7
Maintenance and care
WARNING
■When replacing wheels
●Do not use wheels that are a different size from those recommended in
the Owner’s Manual, as this may result in a loss of handling control.
●Never use an inner tube in a leaking wheel which is designed for a
tubeless tire. Doing so may result in an accident, causing death or seri-
ous injury.
■When installing the wheel nuts
●Never use oil or grease on the wheel bolts or wheel nuts.
Oil and grease may cause the wheel nuts to be excessively tightened,
leading to bolt or disc wheel damage. In addition, the oil or grease can
cause the wheel nuts to loosen and the wheel may fall off, causing an
accident and resulting in death or serious injury. Remove any oil or
grease from the wheel bolts or wheel nuts.
■Use of defective wheels prohibited
Do not use cracked or deformed wheels.
Doing so could cause the tire to leak air during driving, possibly causing
an accident.
NOTICE
■Replacing tire pressure warning valves and transmitters
●Because tire repair or replacement may affect the tire pressure warn-
ing valves and transmitters, make sure to have tires serviced by your
Toyota dealer or other qualified service shop. In addition, make sure to
purchase your tire pressure warning valves and transmitters at your
Toyota dealer.
●Ensure that only genuine Toyota wheels are used on your vehicle.
Tire pressure warning valves and transmitters may not work properly
with non-genuine wheels.
●Be sure to install the wheel nuts with
the tapered ends facing inward.
Installing the nuts with the tapered
ends facing outward can cause the
wheel to break and eventually cause
the wheel to come off while driving,
which could lead to an accident
resulting in death or serious injury.Tapered
portion
Page 461 of 624
PRIUS v_OM_OM47B23U_(U)
4617-3. Do-it-yourself maintenance
7
Maintenance and care
■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.
NOTICE
■When using the ai r conditioning system
Make sure that a filter is always installed.
Using the air conditioning system without a filter may cause damage to the
system.
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