2010 TOYOTA PRIUS coolant reservoir

425
4-3. Do-it-yourself maintenance
4
Maintenance and care
PRIUS_U (OM47668U) U.S.A.
Engine compar tment
■12 volt battery
 P. 436
Engine coolant reservoir 
(  P. 430)
Engine oil level dipstick 
(  P. 426)
Engine oil filler cap 
(  P. 427)
Power control unit coolant
reservoir ( P. 430)Brake fluid reservoir 
(  P. 432)
Fuse box ( P. 462)
Radiator ( P. 432)
Condenser ( P. 432)
Electric cooling fans
Washer fluid tank 
( P. 434)

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.
ITO43P111
■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.

431
4-3. Do-it-yourself maintenance
4
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.

474 4-3. Do-it-yourself maintenance
PRIUS_U (OM47668U) U.S.A.
Replacing light bulbs■ Headlight low beams (halogen bulbs)
For the right side only: 
Remove the bolt and unclip the
engine coolant reservoir hose.
Then lift up the air cleaner inlet
duct.
Turn the bulb base counterclock-
wise.
STEP1
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STEP2

476 4-3. Do-it-yourself maintenance
PRIUS_U (OM47668U) U.S.A.■
Headlight high beams
For the right side only: Remove the bolt and unclip the engine
coolant reservoir hose. Then lift up the air cleaner inlet duct.
( P. 474)
Turn the bulb base counterclockwise.
Vehicles with LED headlights
Vehicles with halogen headlights
Unplug the connector while
pushing the lock release.
STEP1
STEP2
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STEP3

477
4-3. Do-it-yourself maintenance
4
Maintenance and care
PRIUS_U (OM47668U) U.S.A.
■
Parking lights
For the right side only: Remove the bolt and unclip the engine
coolant reservoir hose. Then lift up the air cleaner inlet duct.
( P. 474)
Turn the bulb base counterclockwise.
Vehicles with LED headlights
Vehicles with halogen headlights
Remove the light bulb.
STEP1
STEP2
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STEP3

478 4-3. Do-it-yourself maintenance
PRIUS_U (OM47668U) U.S.A.■
Front side marker lights
For the right side only: Remove the bolt and unclip the engine
coolant reservoir hose. Then lift up the air cleaner inlet duct.
( P. 474)
Turn the bulb base counterclockwise.
Vehicles with LED headlights
Vehicles with halogen headlights
Remove the light bulb.
STEP1
STEP2
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STEP3

552 5-2. Steps to take in an emergency
PRIUS_U (OM47668U) U.S.A.
CAUTION
■To prevent an accident or injury when inspecting under the hood of
your vehicle
● If steam is seen coming from under the hood, do not open the hood until
the steam has subsided. The engine compartment may be very hot, caus-
ing serious injury such as burns.
● With a hybrid vehicle, there are times when the gasoline engine automati-
cally starts to run or the cooling fans suddenly start to operate. Do not
touch or approach the rotating parts of the belt or fans. Doing so may lead
to fingers, clothes or tools getting caught, resulting in an accidental injury.
● Do not loosen the coolant reservoir cap while the hybrid system and radia-
tor are hot. 
Serious injury, such as burns, may result from hot coolant and steam
released under pressure.
NOTICE
■ When adding engine/power control unit coolant
Wait until the hybrid system has cooled down before adding engine/power
control unit coolant. 
When adding coolant, do so slowly. Adding cool coolant to a hot hybrid sys-
tem too quickly can cause damage to the hybrid system.