2012 TOYOTA PRIUS cooling

550 5-2. Steps to take in an emergency
Check to see if the cooling fans are operating.
If the fans are operating: Wait until the high coolant temperature warning light goes
off and then stop the hybrid system.
If the fans are not operating: Stop the hybrid system immediately and call your Toyota
dealer.
After the hybrid system has
cooled down sufficiently, check
the engine coolant level and
inspect the cooling system for
leaks.
If necessary, add engine coolant
up to the “FULL” line.
Water can be used in an emer-
gency measure if engine coolant
is unavailable. (P. 566)
Have the vehicle checked at nearest Toyota dealer as soon as possi-
ble.
STEP 3
STEP 4
ITO52P130
STEP 5

5
When trouble arises
551
5-2. Steps to take in an emergency
■
If “HYBRID SYSTEM OVERHEAT” is shown on the multi-infor-
mation display
Stop the vehicle in a safe place and turn off the air condition-
ing system.
Leave the hybrid system operating and carefully lift the hood.
Check if the cooling fans are operating.
If the fans are operating: Wait until “HYBRID SYSTEM OVERHEAT” disappears and
then stop the hybrid system.
If the warning light does not turn off, call your Toyota dealer.
If the fans are not operating: Stop the hybrid system immediately and call your Toyota
dealer.
After the hybrid system has
cooled down, check the power
control unit coolant level and
inspect the cooling system for
leaks.
STEP 1
STEP 2
STEP 3
STEP 4

5
When trouble arises
553
5-2. Steps to take in an emergency
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 injuries such as burns.
● Check that the indicator on the “POWER” switch and the “READY” indica-
tor are off.
● For vehicles with a hybrid system, there are times when the gasoline
engine automatically starts to run or the cooling fans suddenly start to
operate. Do not touch or approach the rotating parts of the fans, etc. Doing
so may lead to fingers, clothes or tools getting caught, resulting in 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.
■ To prevent damage to the cooling system
Observe the following precautions:
●Avoid contaminating the coolant with foreign matter (such as sand or dust
etc.)
● Do not use commercially available coolant additives

566 6-1. Specifications
Cooling system
Ignition system
Capacity
Gasoline
engine
Without an exhaust heat recovery system
6.9 qt. (6.5 L, 5.7 Imp.qt.)
With an exhaust heat recovery system
7.6 qt. (7.2 L, 6.3 Imp.qt.)
Power
control
unit2.2 qt. (2.1 L, 1.8 Imp.qt.)
Coolant type Use either of the following:
• “Toyota Super Long Life Coolant”
• Similar high-quality ethylene glycol-based non- silicate, non-amine, non-nitrite, and non-borate
coolant with long-life hybrid organic acid technol-
ogy
Do not use plain water alone.
Spark plug
Make DENSO SC20HR11
Gap 0.043 in. (1.1 mm)
NOTICE
■Iridium-tipped spark plugs
Use only iridium-tipped spark plugs. Do not adjust the spark plug gap.

595
6-2. Customization
6
Vehicle specifications
ItemFunctionDefault set-
tingCustom-ized
setting
Meter and
instrument
panel
( P. 214) Sensor sensitiv-
ity for darkening
the brightness of
the meter, navi-
gation system
and instrument
panel depend-
ing on the out-
side brightness
0-2 to +2––O
Sensor sensitiv-
ity for returning
the brightness of
the meter, navi-
gation system
and instrument
panel to the orig-
inal level
depending on
the outside
brightness 0-2 to +2––O
Automatic
air
conditioning
system
( P. 326) Enable/disable
automatic
operation of the
air conditioning
compressor
when the
“AUTO” switch
ON
ON OFF – O O
Heating/cooling
operation mini-
mized in Eco
drive mode ON OFF – – O

620 Alphabetical index
Child safetyAirbag precautions ................148
Back door precautions ............95
Child restraint system............ 160
Child-protectors .......................88
How your child should wear
the seat belt ........................ 111
Installing child restraints ........ 165
Power window lock switch..... 123
Power window precautions ... 125
Removed electronic key battery
precautions ......................... 455
Seat belt extender precautions ......................... 116
Seat belt precautions ............ 112
Seat heater precautions ........ 370
12-volt battery precautions .... 434
Child-protectors .........................88
Cleaning Exterior .................................. 396
Interior ................................... 399
Seat belts .............................. 400
Clock ......................................... 230
Condenser ................................ 426
Console box ............................. 359
Cooling system
Engine overheating ............... 549
Hybrid system overheating.... 549
Cruise control
Cruise control ........................ 266
Dynamic radar cruise control ................................. 270
Cup holders .............................. 360
Curtain shield airbags ............. 140
Customizable features............. 590 Daytime running light
system .................................... 253
Deck board ............................... 374
Defogger Rear window ......................... 346
Side mirrors........................... 346
Dimensions .............................. 560
Dinghy towing .......................... 323
Display Dynamic radar cruise control ................................. 270
Multi-information ................... 223
Warning messages ............... 507
Do-it-yourself maintenance .... 410
Door lock
Back door ................................ 93
Side doors ............................... 87
Smart key system .. ................. 61
Wireless remote control .......... 85
Doors
Back door ................................ 93
Door glasses ......................... 123
Door lock ..................... 61, 85, 87
Rear door child-protector ........ 88
Side doors ............................... 87
Driver’s seat belt reminder
light ......................................... 498
Driving Break-in tips .......................... 181
Correct posture ..................... 138
Procedures............................ 180
Winter driving tips ................. 317D