2023 TOYOTA PRIUS PLUG-IN HYBRID coolant reservoir

5877-3. Do-it-yourself maintenance
Prius Plug-in Hybrid_OM_OM47F38E_(EE)
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Maintenance and care
Engine compar tment
IO73PH114
Engine coolant reservoir
( P. 591)
Fuse boxes ( P. 635)
Engine oil level dipstick
( P. 588)
Engine oil filler cap ( P. 589)
Washer fluid tank ( P. 598)
12-volt battery ( P. 594)
Power control unit coolant
reservoir ( P. 591)
Radiator ( P. 593)
Condenser ( P. 593)
Electric cooling fans
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5917-3. Do-it-yourself maintenance
Prius Plug-in Hybrid_OM_OM47F38E_(EE)
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Maintenance and care
The coolant level is satisfactory if it is between the “MAX” and “MIN”
lines on the reservoir when the hybrid system is cold.
■Engine coolant reservoir
Reservoir cap
“MAX” line
“MIN” line
If the level is on or below the
“MIN” line, add coolant up to the
“MAX” line. ( P. 705)
■Power control unit coolant reservoir
Reservoir cap
“FULL” line
“LOW” line
If the level is on or below the
“LOW” line, add coolant up to
the “FULL” line. ( P. 705)
Coolant
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5927-3. Do-it-yourself maintenance
Prius Plug-in Hybrid_OM_OM47F38E_(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.

7068-2. Steps to take in an emergency
Prius Plug-in Hybrid_OM_OM47F38E_(EE)
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 the radiator or hoses.
The fans operate when the temperature setting is adjusted to “LO” and
“A/C” switch ( ) is turned on immediately after a cold start. Con-
firm that the fans are operating by checking the fan sound and air flow. If
it is difficult to check these, turn the “A/C” switch ( ) 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.
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7078-2. Steps to take in an emergency
Prius Plug-in Hybrid_OM_OM47F38E_(EE)
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When trouble arises
■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.
The coolant level is satisfactory 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.
If water was added in an emer-
gency, have the vehicle
inspected at any authorized
Toyota retailer or Toyota autho-
rized repairer, or any reliable
repairer as soon as possible.
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7088-2. Steps to take in an emergency
Prius Plug-in Hybrid_OM_OM47F38E_(EE)
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 does not disappear:
Stop the hybrid system and contact any authorized Toyota
retailer or Toyota authorized repairer, or any reliable repairer.
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 any autho-
rized Toyota retailer or Toyota authorized repairer, or any reliable
repairer.
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. 213) 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.
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