2010 TOYOTA PRIUS maintenance

430 4-3. Do-it-yourself maintenance
PRIUS_U (OM47668U) U.S.A.
Engine/power control unit coolantThe coolant level is satisfactory if it is between the “FULL” and “LOW”
lines on the reservoir when the hybrid system is cold.
Engine coolant reservoir Reservoir cap
“FULL”
“LOW”
If the level is on or below the
“LOW” line, add coolant up to the
“FULL” line.
Power control unit coolant reservoirReservoir cap
Full
Low
If the level is on or below the “L”
line, add coolant up to the “F” line.
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■If the coolant level drops within a short time after replenishing
Visually check the radiator, hoses, reservoir cap, radiator cap, drain cock
and water pump. 
If you cannot find a leak, have your Toyota dealer pressure test the cap and
check for leaks in the cooling system.

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Maintenance and care
PRIUS_U (OM47668U) U.S.A.
■
Coolant selection
Only use “Toyota Super Long Life Coolant” or 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 % deionized water. (Enabled: -31 F [-35 C])
Canada: “Toyota Super Long Life Coolant” is a mixture of 55 % coolant and 45 % deionized water. (Enabled: -44 F [-42 C])
For more details about engine coolant, contact your Toyota dealer.
CAUTION
■ When the hybrid system is hot
Do not remove the coolant reservoir cap. 
The cooling system may be under pressure and may spray hot coolant if the
cap is removed, causing burns or other injuries.
NOTICE
■ When adding the coolant
Coolant is neither plain water not straight antifreeze. The correct mixture of
water and anti freeze 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 damage to parts or paint.

432 4-3. Do-it-yourself maintenance
PRIUS_U (OM47668U) U.S.A.
Radiator and condenserCheck the radiator and condenser and clear any foreign objects. 
If either of the above parts are extr emely dirty or you are not sure of
their condition, have your vehicl e checked by your Toyota dealer.
Brake fluid
■ Checking fluid level
The brake fluid level should be
between the “MAX” and “MIN”
lines on the tank.
CAUTION
■When the hybrid system is hot
Do not touch the radiator or condenser, as they may be hot and may cause
burns.
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433
4-3. Do-it-yourself maintenance
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Maintenance and care
PRIUS_U (OM47668U) U.S.A.
■
Adding fluid
Push the tab in and lift the cover
off.
Make sure to check the fluid type and prepare the necessary items.
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Fluid typeFMVSS No.116 DOT 3 or SAE J1703 brake fluid
ItemsClean funnel
■ Brake fluid can absorb moisture from the air
Excess moisture in the fluid can cause a dangerous loss of braking effi-
ciency. Use only newly opened brake fluid.
CAUTION
■When filling the reservoir
Take care because brake fluid can harm your hands or eyes and damage
painted surfaces. 
If fluid gets in your eyes, flush your eyes with clean water immediately.
If you still experience discomfort, see a doctor.

434 4-3. Do-it-yourself maintenance
PRIUS_U (OM47668U) U.S.A.
Washer fluidOpen the lid.
Check the washer fluid level on
the level gauge.“NORMAL”
“LOW”
NOTICE
■If the fluid level is low
It is normal for the brake fluid level to go down slightly as the brake pads
wear or when the fluid level in the accumulator is high. 
If the reservoir needs frequent refilling, it may indicate a serious pro\
blem.
STEP1
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STEP2

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Maintenance and care
PRIUS_U (OM47668U) U.S.A.
If the washer fluid level is at
“LOW”, add washer fluid.
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STEP3
CAUTION
■
When refilling the washer fluid
Do not refill the washer fluid when the hybrid system is hot or operating, as
the washer fluid contains alcohol and may catch fire if spilled on the hybrid
system etc.
NOTICE
■Do not use any fluid other than washer fluid
Do not use soapy water or engine antifreeze instead of washer fluid. 
Doing so may cause streaking on the vehicle’s painted surfaces.
■ Diluting washer fluid
Dilute washer fluid with water as necessary. 
Refer to the freezing temperatures listed on the washer fluid tank.

436
4-3. Do-it-yourself maintenance
PRIUS_U (OM47668U) U.S.A.
12 volt batter y
■Location
The 12 volt battery is located
in the right-hand side of lug-
gage compartment.
■ Removing the 12 volt battery cover
Open the center auxiliary box. ( P. 385)
Remove the center auxiliary box. ( P. 526)
Remove the 12 volt battery
cover.
Remove the 12 volt battery
maintenance cover.
STEP1
STEP2
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STEP3
STEP4

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Maintenance and care
PRIUS_U (OM47668U) U.S.A.
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Before recharging
When recharging, the 12 volt battery produces hydrogen gas which is flam-
mable and explosive. Therefore, before recharging:
● If recharging with the 12 volt battery installed on the vehicle, be sure to
disconnect the ground cable.
● Make sure the power switch on the charger is off when connecting and
disconnecting the charger cables to the 12 volt battery.
■ 12 volt battery exterior
Make sure that the 12 volt battery terminals are not corroded
and that there are no loose c onnections, cracks, or loose
clamps.
Terminals
Hold-down clamp