2021 TOYOTA PRIUS cooling

6577-2. Steps to take in an emergency
PRIUS_OM_OM47E09U_(U)
7
When trouble arises
The coolant level is satisfactory if it is between the “MAX” and
“MIN” lines on the reservoir.
Reservoir
“MAX” line
“MIN” line
Add coolant if necessary.
Water can be used in an emer-
gency if coolant is unavailable.
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 t he radiator or hoses.
The fans operate when the air conditioning system is turned on immedi-
ately after a cold start. Confirm that the fans are operating b y 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 your Toyota
dealer.
If the fans are operating:
Have the vehicle inspected at the neare st Toyota dealer.
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6587-2. Steps to take in an emergency
PRIUS_OM_OM47E09U_(U)■
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 (radiat or) for any leaks.
Radiator
Cooling fans
If a large amount of coolant
leaks, immediately contact
your Toyota dealer.
The coolant level is satisfactory if it is between the “FULL” a nd
“LOW” lines on the reservoir.
Reservoir
“FULL” line
“LOW” line
Add coolant if necessary.
Water can be used in an emer-
gency if coolant is unavailable.
If water was added in an emer-
gency, have the vehicle inspected
at your Toyota dealer as soon as
possible.
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6597-2. Steps to take in an emergency
PRIUS_OM_OM47E09U_(U)
7
When trouble arises
After stopping the hybrid system and waiting for 5 minutes or
more, start the hybrid system again and check if “Hybrid System
Overheated” is shown on the multi-information display.
If the message d oes not disappear:
Stop the hybrid system and contact your Toyota dealer.
If the message is not displayed:
The hybrid system temperature has dropped and the vehicle may
be driven normally.
However, if the message appears again frequently, contact your To y o t a
dealer.
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 ho od 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. 116) on the main display and the
“READY” indicator are off.
When the hybrid system is operating, the gasoline engine may au tomati-
cally start, or the cooling fans may suddenly operate even if the gasoline
engine stops. Do not touch or approach rotating parts such as t he 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 syste m and radi-
ator are hot.
High temperature steam or coolant could spray out.
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6607-2. Steps to take in an emergency
PRIUS_OM_OM47E09U_(U)
NOTICE
■When adding engine/power control unit coolant
Add coolant slowly after the hybrid system has cooled down suff iciently.
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 sa nd or dust
etc.).
● Do not use any coolant additive.

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PRIUS_OM_OM47E09U_(U)
8-1. Specifications
*: The coolant capacity is a reference quantity.If replacement is necessary, contact your Toyota dealer.
Cooling system
Capacity*
Gasoline
engine6.6 qt. (6.2 L, 5.5 Imp.qt.)
Power
control unit1.5 qt. (1.4 L, 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
Gap0.035 in. (0.9 mm)
NOTICE
■ Iridium-tipped spark plugs
Use only iridium-tipped spark plugs. Do not adjust the spark pl ug gap.
Electrical system (12-volt battery)
Open voltage at 68F (20 C):
12.0 V or higher
If the voltage is lower than the standard
value, charge the battery. (After charging
the battery, turn on the high beam head-
lights for 30 seconds with the power switch
off, and turn the headlights off.)
Charging rates5 A max.

727Alphabetical index
PRIUS_OM_OM47E09U_(U)
CleaningAluminum wheels.................. 497
Exterior ................................. 496
Front camera ........................ 291
Hybrid battery (traction
battery) air intake vent ........ 551
Interior................................... 502
Radar sensor ........................ 290
Seat belts .............................. 503
Water-repellent coating......... 497
Clock ........................................... 98
Adjustment ............................ 103
Coat hooks ............................... 486
Combination meter .................... 98 Clock adjustment .................. 103
Main display .......................... 115
Multi-information display ....... 124
Warning lights and indicators ............................ 107
Condenser ................................ 524
Console box ............................. 462
Consumption screen ....... 165, 172
Coolant ..................................... 522
Capacity ................................ 670
Checking ............................... 522
Preparing and checking before winter....................... 430
Cooling system ........................ 522 Engine overheating ............... 656
Hybrid system overheating ... 658
Cruise control Cruise control........................ 342
Dynamic radar cruise control with full-speed range .......... 326
Cup holders.............................. 463
Curtain shield airbags ............... 35
Customizable features ............ 690 Daytime running light
system.................................... 266
Deck board ............................... 467
Defogger Outside rear view
mirrors ........................ 440, 450
Rear window ................. 440, 450
Windshield .................... 440, 450
Dimension ................................ 664
Dinghy towing.......................... 244
Display BSM (Blind Spot Monitor) ..... 349
Drive information .................. 126
Dynamic radar cruise control with full-speed range .......... 326
Energy monitor ..... 127, 165, 172
Head-up display.................... 158
Intuitive parking assist .......... 363
LTA (Lane Tracing Assist) .... 316
Main display.......................... 115
Multi-information display ....... 124
Parking Support Brake function............................... 379
RCTA detection screen ........ 349
RSA (Road Sign Assist) ....... 323
S-APGS (Simple Advanced Parking Guidance
System) .............................. 390
Pre-collision warning ............ 297
Trip information..................... 119
Warning messages ............... 603
Do-it-yourself maintenance .... 512
Door courtesy lights ............... 458 Location ................................ 458
Wattage ................................ 674D
*: Refer to “MULTIMEDIA OWNER’S MANUAL”.