Page 585 of 784

PRIUS PRIME_OM_OM47A88U_(U)
5857-3. Do-it-yourself maintenance
7
Maintenance and care
■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.
U.S.A.:
“Toyota Super Long Life Coolant” is a mixture of 50% coolant and 50% deion-
ized water. (Minimum temperature: -31 °F [-35 °C])
Canada:
“Toyota Super Long Life Coolant” is a mixture of 55% coolant and 45% deion-
ized 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 radiator, hoses, engine/power control unit coolant reservoir
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 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 stra ight 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.
Page 586 of 784
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PRIUS PRIME_OM_OM47A88U_(U)
7-3. Do-it-yourself maintenance
Check the radiator and condenser and clear away any foreign objects.
If either of the above parts is ex tremely dirty or you are not sure of
their condition, have yo ur vehicle inspected by your Toyota dealer.
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, t he electric cooling fans may automati-
cally start to run if the air condition ing 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.
Page 667 of 784

6678-2. Steps to take in an emergency
PRIUS PRIME_OM_OM47A88U_(U)
8
When trouble arises
■If “Shift System Malfunction See Owner’s Manual” is shown
Indicates a malfunction in the shift control system. Immediately have the sys-
tem inspected by your Toyota dealer.
The system may not operate properly.
■ If “Low 12-Volt Battery Apply Parking Brake Securely While Parking See
Owner’s Manual” is shown
Indicates that the 12-volt battery charge is insufficient. Charge or replace the
12-volt battery.
● When the message is shown, the hybrid system may not start or the shift
position may not be changed normally. (Coping method: →P. 669)
● After charging the 12-volt battery, the message may not go off until the shift
position is changed from P.
■ If “Shifting Unavailable Low 12-Volt Battery See Owner’s Manual” is
shown
Indicates that the shift position cannot be changed because the voltage of the
12-volt battery drops. Charge or replace the 12-volt battery.
(Coping method in the case the 12-volt battery is discharged: →P. 694)
■ If “Hybrid System Overheated. Re duced Output Power.” is shown
The message may be shown when driving under severe operating conditions.
(For example, when driving up a long steep hill or driving up a steep hill in
reverse.)
Coping method: →P. 700
■ 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. 562.
● When the air intake vents or filters are not dirty and the warning message is
shown, have the vehicle inspected at your Toyota dealer.
■ If “Hybrid Battery Low. Shift Ou t of to Recharge.” is shown
Message is displayed when the remaining charge for the hybrid battery (trac-
tion battery) is low.
As the hybrid battery (traction battery) can not be charged when the shift
position is in N, when stopped for long periods of time shift the shift position to
P.
■ If “Hybrid Battery Low Hybrid Syst em Stopped Shift to and Restart”
is shown
Message is displayed when the remaining charge for the hybrid battery (trac-
tion battery) is low, because vehicle has been shifted to N for a long period of
time.
When operating the vehicle, shift to P and restart the hybrid system.
Page 699 of 784
6998-2. Steps to take in an emergency
PRIUS PRIME_OM_OM47A88U_(U)
8
When trouble arises
NOTICE
■When handling jumper cables
When connecting the jumper cables, ensure that they do not become entan-
gled in the cooling fans, etc.
Page 700 of 784
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PRIUS PRIME_OM_OM47A88U_(U)
8-2. Steps to take in an emergency
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
your Toyota dealer.
The following may indicate that your vehicle is overheating.
● The high coolant temperature warning light ( →P. 655) comes on
or flashes, or a loss of hybrid system power is experienced. (For
example, the vehicle s peed does not increase.)
● “Hybrid System Overhe ated” is shown on the multi-information
display.
● Steam comes out from under the hood.
Correction procedures
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7018-2. Steps to take in an emergency
PRIUS PRIME_OM_OM47A88U_(U)
8
When trouble arises
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.
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 th e radiator or hoses.
The fans operate when the temperature setting is adjusted to “LO” and
“A/C” switch (
*1 • *2) is turned on immediately after a
cold start. Confirm 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
(
*1 • *2) on and off repeatedly. (The fans may not
operate in freezing temperatures.)
*1: Vehicles with 7-inch display
*2: Vehicles with 11.6-inch display
If the fans are not operating:
Stop the hybrid system immediately and contact your Toyota
dealer.
If the fans are operating:
Have the vehicle in spected at the nearest Toyota dealer.
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Page 702 of 784
7028-2. Steps to take in an emergency
PRIUS PRIME_OM_OM47A88U_(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 (radiator) 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” 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 your Toyota dealer as soon as
possible.
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Page 703 of 784

7038-2. Steps to take in an emergency
PRIUS PRIME_OM_OM47A88U_(U)
8
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 does 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 Toyota
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 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. 197) 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.
6