2010 TOYOTA PRIUS cooling

469
4-3. Do-it-yourself maintenance
4
Maintenance and care
PRIUS_U (OM47668U) U.S.A.
FUSEAmpereCircuit
15 P FR DOOR 25A Power windows
16 D FR DOOR 25A Power windows
17 DOOR RR 25A Power windows
18 DOOR RL 25A Power windows
19 S/ROOF 30A Electric moon roof
20 ECU-IG NO.1 10A Electric cooling fans, multiplex
communication system
21 ECU-IG NO.2 10A Driver support system, Pre-Colli-
sion System, LKA system, inside
rear view mirror, garage door
opener, yaw rate & G sensor,
brake system, electric power
steering, navigation system, elec-
tric moon roof, tire pressure warn-
ing system, seat belt
pretensioners, audio system,
emergency flashers, turn signal
lights, windshield wipers, headlight
cleaner
22 GAUGE 10A Headlight leveling system, front
passenger’s seat belt reminder
light, gauges and meters
23 A/C 10A Air conditioning system, Solar
Ventilation System, Remote Air
Conditioning System
24 WASHER 15A Windshield washer

5
When trouble arises
547
5-2. Steps to take in an emergency
PRIUS_U (OM47668U) U.S.A.
NOTICE
■
To prevent damaging the vehicle
The exclusive jump starting terminal is to be used when charging the 12 volt
battery from another vehicle in an emergency. It cannot be used to jump start
another vehicle.
■ When handling jumper cables
Be careful that the jumper cables do not become tangled in the cooling fan
or any of the belts when connecting or disconnecting them.

5
When trouble arises
549
5-2. Steps to take in an emergency
PRIUS_U (OM47668U) U.S.A.
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 immedi ately and call your local
Toyota dealer.
After the hybrid system has
cooled down sufficiently, check
the engine coolant level and
inspect the radiator core (radia-
tor) for any 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. 562)
STEP3
STEP4
ITO52P130
STEP5

550 5-2. Steps to take in an emergency
PRIUS_U (OM47668U) U.S.A.■
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 message does not disapp ear, 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.
STEP1
STEP2
STEP3
STEP4

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.

562 6-1. Specifications
PRIUS_U (OM47668U) U.S.A.
Cooling system
Ignition system
Capacity
Gasoline engine
With an exhaust
heat recovery sys-
tem
Without exhaust
heat recovery sys-
tem
Power control unit7.6 qt. (7.2 L, 6.3 Imp.qt.)
6.9 qt. (6.5 L, 5.7 Imp.qt.)
2.1 qt. (2.0 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 gap when tuning engine.

602 Alphabetical index
PRIUS_U (OM47668U) U.S.A.
CareExterior .................................. 404
Interior ...................................407
Seat belts ..............................408
Cargo capacity .........................260
Cargo hooks ............................. 385
CD player/changer ...................303
Chains ....................................... 263
Child-protectors ......................... 68
Child restraint system Booster seats, definition ........ 132
Booster seats, installation ..... 137
Convertible seats, 
definition ............................. 132
Convertible seats, 
installation ...........................137
Front passenger occupant 
classification system ...........126
Infant seats, definition ...........132
Infant seats, installation.........137
Installing child restraint 
system with 
LATCH system....... ............. 138
Installing child restraint 
system with seatbelts.......... 140
Installing child restraint 
system with top straps ........ 144
Child safety
Airbag precautions ................121
Child restraint system............132
Child-protectors ....................... 68
How your child should wear 
the seatbelt ...........................88
Installing child restraints ........ 137
Moon roof precautions .......... 100
Power window lock switch....... 98
Power window precautions .....99
Removed electronic key 
battery precautions ............. 461
Seat belt precautions ..............89
Back door ................................72 Cleaning
Exterior.................................. 404
Interior ................................... 407
Seat belts .............................. 408
Clock ......................................... 201
Condenser ................................ 432
Console box ............................. 369
Cooling system Hybrid system overheating ... 548
Cruise control Cruise control ........................ 214
Dynamic radar 
cruise control ...................... 218
Cup holders .............................. 372
Curtain shield airbags ............. 113
Customizable features ............ 587
Daytime running light 
system .................................... 207
Defogger Rear window ......................... 289
Side mirror ............................ 289
Dimension ................................ 556
Dinghy towing .......................... 267
Display Trip information ..................... 188
Warning messages ............... 508
Do-it-yourself maintenance .... 416
Door courtesy lights ................ 363
Door lock Back door ................................ 72
Side doors ............................... 67
Smart key system .. ................. 43
Wireless remote control .......... 63
Doors Back door ................................ 72
Side doors ............................... 67
Rear door child protector ........ 68C
D