2020 TOYOTA PRIUS C cooling

4227-3. Do-it-yourself maintenance
PRIUS c_U
Engine compartment
Fuse boxes (P. 4 5 4 )
Engine oil filler cap ( P. 4 2 4 )
Engine coolant radiator cap
Power control unit
coolant reservoir ( P. 4 2 6 )
Brake fluid reservoir ( P. 4 2 8 )
Engine coolant reservoir ( P. 4 2 6 ) Engine/power control unit
coolant radiator (
P. 428)
Electric cooling fan
Condenser ( P. 428)
Engine oil level dipstick ( P. 423)
Washer fluid tank ( P. 430)1
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4277-3. Do-it-yourself maintenance
7
Maintenance and care
PRIUS c_U
■Coolant selection
Only use “Toyota Super Long Life Coolant” or a similar high quality ethylene
glycol based non-silicate, non-amine, non-nitrite, and non-bora te coolant with
long-life hybrid organic acid technology.
U.S.A.:
“Toyota Super Long Life Coolant” is a mixture of 50% coolant an d 50%
deionized water. (Minimum temperature: -31 F [-35 C])
Canada:
“Toyota Super Long Life Coolant” is a mixture of 55% coolant an d 45%
deionized water. (Minimum temperature: -44 F [-42 C])
For more details about coolant, contact your Toyota dealer.
■ If the coolant level drops within a short time of replenishing
Visually check the radiators, hoses, engine/power control unit coolant reser-
voir caps, drain cock and water pump.
If you cannot find a leak, have your Toyota dealer test the cap and check for
leaks in the cooling systems.
WARNING
■ When the hybrid system is hot
Do not remove the engine coolant radiator cap and power control unit cool-
ant reservoir cap.
The cooling system may be under pressure and may spray hot coolant if the
cap is removed, causing serious injuries, such as burns.
NOTICE
■ When adding coolant
Coolant is neither plain water nor straight antifreeze. The cor rect mixture of
water and antifreeze 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 from damaging p arts or paint.

4998-2. Steps to take in an emergency
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When trouble arises
PRIUS c_U
Carrying out the corresponding action turns the message off.
After taking the specified steps to correct the suspected probl em,
check that the warning m essage and light go off.
Other displayed message
Displayed messageDetails/Actions
Maintenance of the hybrid battery (traction battery)
cooling component is required
The filter may be clogged, the air intake vent
may be blocked or there may be a gap in the
duct.
 If the air intake vent is dirty, refer to P. 404
for cleaning the air intake vent.
 If the message is being displayed and the air
intake vent is not dirty, have the vehicle
inspected at your Toyota dealer.
Have the malfunction repaired immediately. (vehicles with a
smart key system)
Interior
buzzerExterior buzzerWarning messageDetails/Actions
Once  The electronic key is not
detected when an attempt is
made to start the hybrid sys-
tem.

Start the hybrid system
with the electronic key
present.
(Flashes)

5288-2. Steps to take in an emergency
PRIUS c_U
WARNING
■12-volt battery precautions
The 12-volt battery contains poisonous and corrosive acidic ele ctrolyte,
while related parts contain lead and lead compounds. Observe th e following
precautions when handling the 12-volt battery:
● When working with the 12-volt battery, always wear safety glass es and
take care not to allow any battery fluids (acid) to come into c ontact with
skin, clothing or the vehicle body.
● Do not lean over the 12-volt battery.
● In the event that battery fluid comes into contact with the skin or eyes,
immediately wash the affected area with water and seek medical attention.
Place a wet sponge or cloth over the affected area until medica l attention
can be received.
● Always wash your hands after handling the 12-volt battery suppo rt, termi-
nals, and other 12-volt battery-related parts.
● Do not allow children near the 12-volt battery.
■ When replacing the 12-volt battery
After replacing, securely attach the exhaust hose and exhaust h ole plug to
the exhaust hole of the exchanged 12-volt battery. If not properly installed,
gases (hydrogen) may leak into the vehicle interior, and there is a possible
danger of the gas igniting and exploding.
NOTICE
■ When handling jumper cables
When connecting the jumper cables, ensure that they do not beco me entan-
gled in the cooling fan or belt.
■ To prevent damaging the vehicle
The exclusive jump starting terminal is to be used when chargin g the 12-volt
battery from another vehicle in an emergency. It cannot be used to jump
start another vehicle.

5298-2. Steps to take in an emergency
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When trouble arises
PRIUS c_U
● ( P. 489) is shown on the mu lti-information display.
● The hybrid system overheat warning message ( P. 493) is shown
on the multi-information display.
● Steam comes out f rom under the hood.
■If is shown on the mult i-information display
Stop the vehicle in a safe place and turn off the air conditioning
system, and then stop the hybrid system.
If you see steam:
Carefully lift the hood after the steam subsides.
If you do not see steam:
Carefully lift the hood.
After the hybrid system has
cooled down sufficiently,
inspect the hoses and radia-
tor core (radiator) for any
leaks. Radiator
Cooling fan
If a large amount of coolant
leaks, immediately contact
your Toyota dealer.
If your vehicle overheats
The following may indicate that your vehicle is overheating.
Correction procedures
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5308-2. Steps to take in an emergency
PRIUS c_U
The coolant level is satisfac-
tory if it is between the
“FULL” and “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.
Start the hybrid system and turn the air conditioning system on to
check that the radiator cooling fan operates and to check for
coolant leaks from t he radiator or hoses.
The fan operates when the air conditioning system is turned on immedi-
ately after a cold start. Confirm that the fan is operating by checking the
fan sound and air flow. If it is difficult to check these, turn the air condi-
tioning system on and off repeatedly.
(The fan may not operate in freezing temperatures.)
If the fan is not operating:
Stop the hybrid system immediately and contact your Toyota
dealer.
If the fan is operating:
Have the vehicle inspected at the neare st Toyota dealer.
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5318-2. Steps to take in an emergency
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When trouble arises
PRIUS c_U■
If the hybrid system overheat warning message is shown on
the multi-information 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 fan
If a large amount of coolant
leaks, immediately contact
your Toyota dealer.
The coolant level is satisfac-
tory if it is between the “F”
and “L” lines on the reservoir.
Reservoir
“F” line
“L” line
Add coolant if necessary.
Water can be used in an emer-
gency if coolant is unavailable.
Start the hybrid system and chec k for the multi-information dis-
play.
If the message d oes not disappear:
Stop the hybrid system and contact your Toyota dealer.
If the message is not displayed:
Have the vehicle inspected at the neare st Toyota dealer.
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5328-2. Steps to take in an emergency
PRIUS c_U
WARNING
■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 ho od until
the steam has subsided. The engine compartment may be very hot, caus-
ing serious injuries such as burns.
● After the hybrid system has been turned off, check that on the multi-
information display and the “READY” indicator are off.
When the hybrid system is operating, the gasoline engine may au tomati-
cally start, or the cooling fan may suddenly operate even if th e 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 radiator cap while the hybrid system and radi ator are
hot.
Serious injuries, such as burns, may result from hot coolant an d 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 sa nd or dust
etc.).
● Do not use any coolant additive.