2023 TOYOTA PRIUS cooling

6477-2. Steps to take in an emergency
PRIUS_OM_OM47F32E_(EE)
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When trouble arises
Start the hybrid system and turn the air conditioning system on to
check that the radiator cooling fans operate and to check for
coolant leaks from the radiator or hoses.
The fans operate when the air condi tioning system is turned on immedi-
ately after a cold start. Confirm that the fans are operating by checking
the fan sound and air flow. If it is difficult to check these, turn the air con-
ditioning system on and off repeatedly. (The fans may not operate in
freezing temperatures.)
If the fans are not operating:
Stop the hybrid system immediately and contact any authorized
Toyota retailer or Toyota authorized repairer, or any reliable
repairer.
If the fans are operating:
Have the vehicle inspected at the nearest any authorized Toyota
retailer or Toyota authorized repairer, or any reliable repairer.
■If “Hybrid System Overheated” is shown on the multi-informa-
tion display
Stop the vehicle in a safe place.
Stop the hybrid system and carefully lift the hood.
After the hybrid system has cooled down, inspect the hoses and
radiator core (radiator) for any leaks.
Radiator
Cooling fans
If a large amount of coolant
leaks, immediately contact
any authorized Toyota retailer
or Toyota authorized repairer,
or any reliable repairer.
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6497-2. Steps to take in an emergency
PRIUS_OM_OM47F32E_(EE)
7
When trouble arises
WARNING
■To prevent an accident or injury when inspecting under the hood of
your vehicle
Observe the following precautions.
Failure to do so may result in serious injury such as burns.
● 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.
● After the hybrid system has been turned off, check that the “Accessory”,
“Ignition ON” or mileage display ( P. 118, 120) on the main display and
the “READY” indicator are off.
When the hybrid system is operating, the gasoline engine may automati-
cally start, or the cooling fans may suddenly operate even if the gasoline
engine stops. Do not touch or approach rotating parts such as the fan,
which may lead to fingers or clothing (especially a tie, a scarf or a muffler)
getting caught, resulting in serious injury.
● Do not loosen the coolant reservoir caps while the hybrid system and radi-
ator are hot.
High temperature steam or coolant could spray out.
NOTICE
■ When adding engine/power control unit coolant
Add coolant slowly after the hybrid system has cooled down sufficiently.
Adding cool coolant to a hot hybrid system 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 any coolant additive.

6628-1. Specifications
PRIUS_OM_OM47F32E_(EE)
*: The fluid capacity is the quantity of reference.
If replacement is necessary, contact any authorized Toyota retailer or
Toyota authorized repairer, or any reliable repairer.
Cooling system
Capacity*
Gasoline
engine
Without exhaust heat recirculator system
5.6 L (5.9 qt., 4.9 Imp.qt.)
With exhaust heat recirculator system
6.2 L (6.6 qt., 5.5 Imp.qt.)
Power
control unit1.4 L (1.5 qt., 1.2 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 technology
Do not use plain water alone.
Ignition system (spark plug)
MakeDENSO FC16HR-CY9
Gap0.9 mm (0.035 in.)
NOTICE
■ Iridium-tipped spark plugs
Use only iridium-tipped spark plugs. Do not adjust the spark plug gap.

688Alphabetical index
PRIUS_OM_OM47F32E_(EE)
Care ................................... 496, 502
Aluminum wheels .................. 497
Exterior.................................. 496
Front camera......................... 285
Interior ................................... 502
Radar sensor ........................ 284
Seat belts .............................. 503
Water-repellent coating ......... 497
Cargo hooks ............................. 480
Catch protection function ....... 211
Chains ....................................... 453
Child restraint system ............... 54
Child restraint system
installation method................ 67
Fixed with a seat belt .............. 68
Fixed with an ISOFIX lower
anchorage............................. 70
Points to remember................. 54
Riding with children ................. 53
Using a top tether
anchorage............................. 72
Child safety ................................ 53
12-volt battery precautions.... 524
Airbag precautions .................. 41
Back door precautions .......... 184
Child restraint system ............. 54
How your child should wear
the seat belt .......................... 36
Installing child restraints.......... 67
Moon roof precautions .......... 218
Power window lock switch .... 210
Power window precautions ... 213
Rear door child-protectors .... 180
Removed key battery
precautions ......................... 556
Riding with children ................. 53
Seat belt precautions .............. 69
Seat heater precautions ........ 468Child-protectors....................... 180
Cleaning ........................... 496, 502
Aluminum wheels.................. 497
Exterior ................................. 496
Front camera ........................ 285
Hybrid battery (traction
battery) air intake vent ........ 545
Interior................................... 502
Radar sensor ........................ 284
Seat belts .............................. 503
Water-repellent coating......... 497
Clock ......................................... 100
Adjustment ............................ 106
Coat hooks ............................... 493
Combination meter .................. 100
Clock adjustment .................. 106
Main display .......................... 117
Multi-information display ....... 127
Warning lights and
indicators ............................ 110
Condenser ................................ 520
Console box ............................. 474
Coolant ..................................... 518
Capacity ................................ 662
Checking ............................... 518
Preparing and checking
before winter....................... 452
Cooling system ........................ 518
Engine overheating ............... 645
Hybrid system overheating ... 647
Consumption screen ............... 166
Cruise control
Cruise control........................ 346
Dynamic radar cruise control
with full-speed range .......... 329
Cup holders.............................. 475
Curtain shield airbags ............... 39
Customizable features ............ 670
C