2020 TOYOTA PRIUS PLUG-IN HYBRID cooling

5826-1. Using the air conditioning system and defogger
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
■Operation of the air conditioning system when the blower customization
is set to “ECO”
●In the “ECO” mode, the air conditioning system is controlled as follows to
prioritize fuel efficiency:
• Engine speed and compressor operation controlled to restrict heating/
cooling capacity
• Fan speed restricted when automatic mode is selected
●To improve air conditioning performance, perform the following operations:
• Adjust the fan speed
• Adjust the temperature setting
• Set the blower customization to “FAST” or “NORMAL” mode.
●When the driving mode is set to Eco driving mode, the fan speed setting
mode will be changed to “ECO” mode automatically. Even in this case, the
fan speed control mode can be changed by pressing . (P. 468)
■When the outside temperature falls to nearly 0C (32F)
The dehumidification function may not operate even when is pressed.
■Ventilation and air conditioning odors
●To let the fresh air in, set the air conditioning system to the outside air mode.
●During use, various odors from inside and outside the vehicle may enter into
and accumulate in the air conditioning system. This may then cause odor to
be emitted from the vents.
●In order to suppress odors that occur when the air conditioning system
starts, fresh air is automatically taken in when parked.
●To reduce potential odors from occurring, the start timing of the blower may
be delayed for a short period of time immediately after the air conditioning
system is started in automatic mode.
■Air conditioning filter
P. 681
■Customization
Settings (e.g. A/C auto switching operation) can be changed.
(Customizable features: P. 782)

5886-1. Using the air conditioning system and defogger
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
WARNING
■Precautions for the Remote Air Conditioning System
● Do not use the system if people are in the vehicle.
Even when the system is in use, the internal temperature may still reach a
high or low level due to features such as the automatic shut-off. Children
and pets left inside the vehicle may suffer heatstroke dehydration or hypo-
thermia, or could result in death or serious injury.
● Depending on the surrounding environment, signals from the wireless
switch may transmit further than expected. Pay appropriate attention to
the vehicle’s surroundings and use the switch only when necessary.
● Do not operate “A/C” if the hood is open. The air conditioning may operate
unintentionally and objects may be drawn into the electrical cooling fan.
NOTICE
■ To prevent the hybrid battery (traction battery) from being discharged
through incorrect operation
Use “A/C” only when necessary.

6237-1. Maintenance and care
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
7
Maintenance and care
Clean the air intake vents and fil-
ters by the following procedures to
prevent dust from accumulating in
them, or to prevent them from
clogging.
The filters are attached to the back
side of the air intake vent grilles.
■
Cleaning the air intake vents and filters
Remove the dust from the vents
and filters with a vacuum
cleaner etc.
Clean the vents of the both
sides.
■
Cleaning the filters
If “Maintenance required for Traction battery cooling parts See
owner’s manual” is shown on the multi-information display, remove
the air intake vent grilles on the both sides of the rear seat and
clean the filters.
Insert a flathead screwdriver
etc. to the notch at the edge
of the grille to disconnect the
3 tabs, and remove the grille.
Turn over the rubber portion
beside the grille to insert the flat-
head screwdriver.
To prevent damage, cover the
tip of the flathead screwdriver
with a rag.
Cleaning the air intake vents and filters
1

6257-1. Maintenance and care
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
7
Maintenance and care
■Caring for leather areas
Toyota recommends cleaning the interior of the vehicle at least twice a year to
maintain the quality of the vehicle’s interior.
■Shampooing the carpets
There are several commercial foaming-type cleaners available. Use a sponge
or brush to apply the foam. Rub in overlapping circles. Do not use water.
Wipe dirty surfaces and let them dry. Excellent results are obtained by keep-
ing the carpet as dry as possible.
■Seat belts
Clean with mild soap and lukewarm water using a cloth or sponge. Also
check the belts periodically for excessive wear, fraying or cuts.
■Cleaning the air intake vents and filters
●Dust on the air intake vents or filters may interferes cooling of the hybrid bat-
tery (traction battery) and results in poor electricity and fuel consumption.
Clean the air intake vents and filters periodically.
●If continuing to drive the vehicle with “Maintenance required for Traction bat-
tery cooling parts See owner’s manual” shown on the multi-information dis-
play, the hybrid battery (traction battery) may overheat, leading to
decreasing in distance that can be driven using the electric motor. It may
cause poor electricity and fuel consumption or a malfunction. If the warning
message is shown, clean the air intake vents and filters immediately.
●Improper handling may result in damage to the grille or filters. If you have
any concerns about cleaning the filters, contact any authorized Toyota
retailer or Toyota authorized repairer, or any reliable repairer.
●If the warning message on the multi-information display does not disappear
after cleaning the filters, have the vehicle inspected by any authorized
Toyota retailer or Toyota authorized repairer, or any reliable repairer.
●Timing of cleaning filters differs depending on the use environment of the
vehicle.

6327-3. Do-it-yourself maintenance
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
WARNING
The engine compartment contains many mechanisms and fluids that may
move suddenly, become hot, or become el ectrically energized. To avoid death
or serious injury, observe the following precautions.
■ When working on the engine compartment
● Make sure that the “Accessory”, “Ignition ON” or mileage display (P. 223)
on the main display and the “READY” indicator are both off.
● Keep hands, clothing and tools away from the moving fan.
● Be careful not to touch the engine, power control unit, radiator, exhaust
manifold, etc. right after driving as they may be hot. Oil and other fluids
may also be hot.
● Do not leave anything that may burn easily, such as paper and rags, in the
engine compartment.
● Do not smoke, cause sparks or expose an open flame to fuel. Fuel fumes
are flammable.
● Be extremely cautious when working on the 12-volt battery. It contains poi-
sonous and corrosive sulfuric acid.
● Take care because brake fluid can harm your hands or eyes and damage
painted surfaces. If fluid gets on your hands or in your eyes, flush the
affected area with clean water immediately. If you still experience discom-
fort, consult a doctor.
■ When working near the electric cooling fans or radiator grille
Be sure the power switch is off.
With the power switch in ON mode, the electric cooling fans may automati-
cally start to run if the air conditioning is on and/or the coolant temperature
is high. ( P. 643)
■ Safety glasses
Wear safety glasses to prevent flying or falling material, fluid spray, etc.
from getting in your eyes.

6377-3. Do-it-yourself maintenance
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
7
Maintenance and care
Engine compartment
IO73PH114
Engine coolant reservoir
( P. 641)
Fuse boxes ( P. 691)
Engine oil level dipstick
( P. 638)
Engine oil filler cap ( P. 639)
Washer fluid tank ( P. 648)
12-volt battery ( P. 644)
Power control unit coolant
reservoir ( P. 641)
Radiator ( P. 643)
Condenser ( P. 643)
Electric cooling fans
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6427-3. Do-it-yourself maintenance
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
■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-borate coolant with
long-life hybrid organic acid technology.
“Toyota Super Long Life Coolant” is a mixture of 50% coolant and 50% deion-
ized water. (Minimum temperature: -35 C [-31F])
For more details about coolant, contact any authorized Toyota retailer or
Toyota authorized repairer, or any reliable repairer.
■ If the coolant level drops within a short time of replenishing
Visually check the radiator, hoses, engine/power control unit coolant reservoir
caps, drain cock and water pump.
If you cannot find a leak, have any authorized Toyota retailer or Toyota autho-
rized repairer, or any reliable repairer, test the cap and check for leaks in the
cooling system.
WARNING
■ When the hybrid system is hot
Do not remove the engine/power control unit coolant reservoir caps.
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 correct 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 parts or paint.

6437-3. Do-it-yourself maintenance
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
7
Maintenance and care
Check the radiator and condenser and clear away any foreign objects.
If either of the above parts is extremely dirty or you are not sure of
their condition, have your vehicle inspected by any authorized Toyota
retailer or Toyota authorized repairer, or any reliable repairer.
Radiator and condenser
WARNING
■ When the hybrid system is hot
Do not touch the radiator or condenser as they may be hot and cause seri-
ous injuries, such as burns.
■ When the electric cooling fans are operating
Do not touch the engine compartment.
With the power switch in ON mode, the electric cooling fans may automati-
cally start to run if the air conditioning is on and/or the coolant temperature
is high. Be sure the power switch is off when working near the electric cool-
ing fans or radiator grille.