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7-3. Do-it-yourself maintenance
■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 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 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.
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PRIUS v_OM_OM47B78U_(U)
4217-3. Do-it-yourself maintenance
7
Maintenance and care
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 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, the electric cooling fans may automati-
cally start to run if the air conditioni ng 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.
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PRIUS v_OM_OM47B78U_(U)
8
When trouble arises
8-2. Steps to take in an emergency
If you think something is wrong
●Fluid leaks under the vehicle
(Water dripping from the air conditioning after use is normal.)
● Flat-looking tires or uneven tire wear
● High coolant temperature warning light flashes or comes on
● Changes in exhaust sound
● Excessive tire squeal when cornering
● Strange noises related to the suspension system
● Pinging or other noises related to the hybrid system
● Engine missing, stumbling or running roughly
● Appreciable loss of power
● Vehicle pulls heavily to one side when braking
● Vehicle pulls heavily to one side when driving on a level road
● Loss of brake effectiveness, spongy feeling, pedal almost touches
the floor
If you notice any of the following symptoms, your vehicle proba-
bly needs adjustment or repair. Contact your Toyota dealer as
soon as possible.
Visible symptoms
Audible symptoms
Operational symptoms
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4808-2. Steps to take in an emergency
PRIUS v_OM_OM47B78U_(U)
LDA indicator (warning buzzer)Indicates that the LDA (Lane D eparture Alert with steering
control) system is not available temporarily or has
detected a malfunction when the warning light is illumi-
nated in yellow and a warning message is displayed on
the multi-information display.
P. 226
High coolant temperature warning light
Changes from a flashing to a solid light when the engine
coolant temperature increases
Immediately stop the vehicle in a safe place. ( P. 528)
(If equipped)
Automatic headlight leveling system warning light
Indicates a malfunction in the automatic headlight leveling
system
Have the vehicle inspected by your Toyota dealer
immediately.
Open door warning light (warning buzzer)*2
Indicates that a door is not fully closed
Check that all the doors are closed.
Low fuel level warning light
Indicates that remaining fuel is approximately 1.6 gal.
(6.0 L, 1.3 Imp.gal.) or less
Refuel the vehicle.
Driver’s and front passenger’s seat belt reminder light
(warning buzzer)
*3
Warns the driver and/or front passenger to fasten their
seat belts
Fasten the seat belt.
If the front passenger’s seat is occupied, the front
passenger’s seat belt also needs to be fastened to
make the warning light (warning buzzer) turn off.
Rear passengers’ seat belt reminder lights (warning
buzzer)
*4
Warns the rear passengers to fasten their seat belts
Fasten the seat belt.
Master warning light
A buzzer sounds and the warning light comes on and
flashes to indicate that the master warning system has
detected a malfunction.
P. 487
Warning lightWarning light/Details/Actions
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PRIUS v_OM_OM47B78U_(U)
8-2. Steps to take in an emergency
If your vehicle overheats
■If the high coolant temperature warning light comes on or
flashesStop 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. 480) comes on
or flashes, or a loss of hybrid system power is experienced. (For
example, the vehicle speed does not increase.)
● The warning message indicating overheat is shown on the multi-
information display. ( P. 492)
● Steam comes out from under the hood.
Correction procedures
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5298-2. Steps to take in an emergency
PRIUS v_OM_OM47B78U_(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 the radiator or hoses.
The fans operate when the air conditioning 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 your Toyota
dealer.
If the fans are operating:
Have the vehicle inspected at the nearest Toyota dealer.
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5308-2. Steps to take in an emergency
PRIUS v_OM_OM47B78U_(U)■
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
your Toyota dealer.
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 your Toyota dealer
as soon as possible.
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5318-2. Steps to take in an emergency
PRIUS v_OM_OM47B78U_(U)
8
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 your Toyota dealer.
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 your Toyota dealer.
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.
6