2019 TOYOTA PRIUS PLUS cooling

3866-3. Do-it-yourself maintenance
PRIUS +_OM_OM47D30E_(EE)
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.
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.
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.

4517-2. Steps to take in an emergency
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When trouble arises
*1: Brake system warning buzzer:
When there is a possible problem that could affect braking performance,
the warning light will come on and a warning buzzer will sound.
Parking brake engaged warning buzzer:
A buzzer will sound if the vehicle is driven at a speed of approximately
5 km/h (3 mph) or more.
*2: If you continue to use the vehicle in this state, the light starts blinking with
buzzer sounds, and you will soon become unable to start the hybrid sys-
tem.
*3: Open door warning buzzer:
The open door warning buzzer sounds to alert one or more of the doors is
not fully closed (with the vehicle having reached a speed of 5 km/h
[3 mph]).
*4: Seat belt buzzer:
The seat belt buzzer sounds to alert the driver, front passenger and rear
passengers that his or her seat belt is not fastened. The buzzer sounds for
30 seconds after the vehicle reaches a speed of 20 km/h (12 mph). Then, if
the seat belt is still unfastened, the buzzer will sound in a different tone for
90 more seconds.
Carrying out the corresponding action turns the warning light off.
Other warning light
Warning lightWarning light/Details/Actions
(If equipped)
Go to service warning light
Indicates that 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.
 Have maintenance performed on the hybrid battery
(traction battery) cooling component at any autho-
rized Toyota retailer or Toyota authorized repairer, or
any reliable repairer.

4707-2. Steps to take in an emergency
PRIUS +_OM_OM47D30E_(EE)
Carrying out the corresponding action turns the messages off.
Other displayed messages
Displayed messageDetails/Actions
Maintenance of the hybrid battery (traction bat-
tery) 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.
 Have maintenance performed on the hybrid
battery (traction battery) cooling compo-
nent at any authorized Toyota retailer or
Toyota authorized repairer, or any reliable
repairer.
Indicates that the EV drive mode is not available*
The reason the EV drive mode is not available
(the vehicle is idling, battery charge is low,
speed is higher than the EV drive mode operat-
ing speed range, accelerator pedal is
depressed too much) may be displayed.
A buzzer also sounds.
 Use the EV drive mode when it becomes
available.

5177-2. Steps to take in an emergency
PRIUS +_OM_OM47D30E_(EE)
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When trouble arises
WARNING
■After recharging the 12-volt battery
Have the 12-volt battery inspected at any authorized Toyota retailer or
Toyota authorized repairer, or any reliable repairer as soon as possible.
If the 12-volt battery is deteriorating, continued use may cause the 12-volt
battery to emit a malodorous gas, whic h may be detrimental to the health of
passengers.
■ When replacing the 12-volt battery
 P. 392
NOTICE
■When handling jumper cables
When connecting the jumper cables, ensure that they do not become entan-
gled in the cooling fans, etc.
■ To prevent damaging the vehicle
The exclusive jump starting terminal is to be used when charging the 12-volt
battery from another vehicle in an emergency. It cannot be used to jump
start another vehicle.

5187-2. Steps to take in an emergency
PRIUS +_OM_OM47D30E_(EE)
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. 449) comes on
or flashes, or a loss of hybrid system power is experienced. (For
example, the vehicle speed does not increase.)
● Vehicles without multi-information display: The hybrid system
overheat warning light ( P. 449) comes on.
● Vehicles with multi-information display: The warning message
indicating overheat is shown on the multi-information display.
( P. 464)
● Steam comes out from under the hood.
Correction procedures
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5197-2. Steps to take in an emergency
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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 the radiator or hoses.
The fans operate when the air condi tioning system is turned on immedi-
ately 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 air con-
ditioning system 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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5207-2. Steps to take in an emergency
PRIUS +_OM_OM47D30E_(EE)
■If the hybrid system overheat warning light comes on or the
warning message indicating overheat 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 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 “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.
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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5217-2. Steps to take in an emergency
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When trouble arises
After stopping the hybrid system and waiting for 5 minutes or
more, start the hybrid system and check for the instrument clus-
ter or multi-information display.
If the hybrid system overheat warning light does not turn off or
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 hybrid system overheat warning light does not come on or
the message is not displayed:
The hybrid system temperature has dropped and the vehicle may
be driven normally.
However, if the warning light comes on again frequently or the message
appears again frequently, contact any authorized Toyota retailer or
Toyota authorized repairer, or any reliable repairer.
WARNING
■ 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 indicator on the
power switch and the “READY” indicator are off.
When the hybrid system is operating, the gasoline engine may automati-
cally start, or the cooling fan 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 cap while the hybrid system and radia-
tor are hot.
High temperature steam or coolant could spray out.
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