2020 TOYOTA PRIUS PLUG-IN HYBRID cooling

7288-2. Steps to take in an emergency
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
■If “Maintenance required for Traction battery cooling parts See owner’s
manual” is shown
There is a possibility that the filter may be clogged, the air intake vent may be
blocked or there may be a gap in the duct.
● When the air intake vents or filters are dirty, clean them by the procedures
on P. 623.
● When the air intake vents or filters are not dirty and the warning message is
shown, have the vehicle inspected at any authorized Toyota retailer or
Toyota authorized repairer, or any reliable repairer.
■ If “Traction Battery Needs to be Protected Refrain From the Use of
Position” is shown
This message may be displayed when the shift position is in N.
As the hybrid battery (traction battery) can not be charged when the shift
position is in N, shift the shift position to P when the vehicle is stopped.
■ If “Traction Battery Needs to be Protected Shift into to Restart” is
shown
This message is displayed when the hybrid battery (traction battery) charge
has become extremely low because the vehicle has been left with the N shift
position selected for a certain amount of time.
When operating the vehicle, shift to P and restart the hybrid system.
■ If “Shift to Before Exiting Vehicle” is shown
Message is displayed when the driver’s door is opened without turning the
power switch to off with the shift position in any position other than P.
Shift the shift position to P.
■ If “Shift is in Release Accelerator Before Shifting” is shown
Message is displayed when the accelerator pedal has been depressed and
the shift position is in N.
Release the accelerator pedal and shift the shift position to D or R.
■ If “Depress Brake When Vehicle is Stopped. Hybrid System may Over-
heat.” is shown
The message may be shown when the accelerator pedal is depressed to hold
the vehicle while the vehicle is stopped on an uphill, etc.
The hybrid system may overheat. Release the accelerator pedal and depress
the brake pedal.
■ If “Shifted to Stop Vehicle to Shift to ” is shown
If the P position switch is pressed while driving, the shift position is changed
to N and the message is shown. ( P. 381)
■ If “Auto Power OFF to Conserve Battery” is shown
The power switch has been turned off by the automatic power off function.
When starting the hybrid system next time, operate the hybrid system for
approximately 5 minutes to recharge the 12-volt battery.

7608-2. Steps to take in an emergency
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
NOTICE
■When handling jumper cables
When connecting the jumper cables, ensure that they do not become entan-
gled in the cooling fans, etc.

7618-2. Steps to take in an emergency
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
8
When trouble arises
If your vehicle overheats
■If the high coolant temperature warning light comes on or
flashes
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 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 following may indicate that your vehicle is overheating.
● The high coolant temperature warning light (P. 716) comes on
or flashes, or a loss of hybrid system power is experienced. (For
example, the vehicle speed does not increase.)
● “Hybrid System Overheated” is shown on the multi-information
display.
● Steam comes out from under the hood.
Correction procedures
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7628-2. Steps to take in an emergency
Prius Plug-in Hybrid_OM_OM47D72E_(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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7638-2. Steps to take in an emergency
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
8
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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7648-2. Steps to take in an emergency
Prius Plug-in Hybrid_OM_OM47D72E_(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. 223) 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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7658-2. Steps to take in an emergency
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
8
When trouble arises
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.

7769-1. Specifications
Prius Plug-in Hybrid_OM_OM47D72E_(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
engine6.2 L (6.6 qt., 5.5 Imp.qt.)
Power
control unit1.5 L (1.6 qt., 1.3 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.