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Other displayed messages
Carrying out the corresponding action turns the message off.
Displayed messageDetailsCorrection procedure
Maintenance of the hybrid sys-
tem (traction battery) cooling
component is required The filter may be clogged, the
air vent may be blocked or
there may be a gap in the
duct. Have maintenance
performed on the
hybrid system
(traction battery)
cooling component
at your Toyota
dealer.
EV drive mode cannot be
switched to. A buzzer also sounds.
The reason why EV drive
mode cannot be used is
shown (may not be shown in
some instances.) Use the EV drive
mode when it
becomes available.
(Flashes
3times) EV drive mode has been auto-
matically canceled.
A buzzer also sounds.
The reason why EV drive
mode cannot be used is
shown (may not be shown in
some instances.) Drive normally for a
short time.
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560 5-2. Steps to take in an emergency
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CAUTION
■After recharging the 12-volt battery
Have the 12-volt battery inspected at your Toyota dealer as soon as possi-
ble.
If the 12-volt battery is deteriorating, continued use may cause the 12-volt
battery to emit a malodorous gas, which may be detrimental to the health of
passengers.
■ When replacing the 12-volt battery
P. 444
NOTICE
■When handling jumper cables
When connecting the jumper cables, ensure that they do not become entan-
gled in the cooling fans, etc.
■ Exclusive jump starting terminal
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.
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If your vehicle overheats
Correction procedures■ If the high coolant temperatur e warning light comes on or
flashes
Stop the vehicle in a safe place and turn off the air condition-
ing 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. 504) comes on
or flashes, or a loss of hybrid system power is experienced. (For
example, the vehicle s peed does not increase.)
● “HYBRID SYSTEM OVERHEAT” ( P. 525) is shown on the
multi-informat ion display.
● Steam comes out from under the hood.
STEP 1
STEP 2
STEP 3
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562 5-2. Steps to take in an emergency
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The coolant level is satisfactory if
it is between the “FULL” and
“LOW” lines on the reservoir.Reservoir
“FULL”
“LOW”
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 conditioning system 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 air conditioning system on and off repeatedly.
(The fans may not operate in freezing temperatures.)
If the fans are not operating: Stop the hybrid system im mediately and contact your
Toyota dealer.
If the fans are operating: Have the vehicle inspected at the nearest Toyota dealer.
ITO43P111
STEP 4
ITO52P130
STEP 5
STEP 6
STEP7
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■
If “HYBRID SYSTEM OVERHEAT” is shown on the multi-infor-
mation 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 “F” and “L” lines
on the reservoir.Reservoir
“F”
“L”
STEP 1
STEP 2
STEP 3
STEP 4
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CAUTION
■
To prevent an accident or injury when inspecting under the hood of
your vehicle
●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, caus-
ing serious injuries such as burns.
● 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 fans may suddenly operate even if the gasoline
engine stops. Do not touch or approach rotating parts such as the fans,
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.
Serious injury, such as burns, may result from hot coolant and steam
released under pressure.
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566 5-2. Steps to take in an emergency
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NOTICE
■When adding engine/power control unit coolant
Wait until the hybrid system has cooled down before adding engine/power
control unit coolant.
When adding coolant, do so slowly. Adding cool coolant to a hot hybrid sys-
tem 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 additives.
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578 6-1. Specifications
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Cooling system
Ignition system
Capacity
Gasoline
engine
Without an exhaust heat recovery system
6.9 qt. (6.5 L, 5.7 Imp.qt.)
With an exhaust heat recovery system
7.6 qt. (7.2 L, 6.3 Imp.qt.)
Power
control
unit2.2 qt. (2.1 L, 1.8 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 technol-
ogy
Do not use plain water alone.
Spark plug
Make DENSO SC20HR11
Gap 0.043 in. (1.1 mm)
NOTICE
■Iridium-tipped spark plugs
Use only iridium-tipped spark plugs. Do not adjust the spark plug gap.