Page 489 of 607
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PRIUS v_OM_OM47B78U_(U)
8
When trouble arises
8-2. Steps to take in an emergency
If a warning message is displayed
Master warning light
The master warning light also
comes on or flashes in order to
indicate that a message is cur-
rently being displayed on the
multi-information display.
Multi-information display
If any of the warning lights come on again after the following actions
have been performed, contact your Toyota dealer.
If a warning is shown on the multi-information display, stay calm
and perform the following actions:
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4938-2. Steps to take in an emergency
PRIUS v_OM_OM47B78U_(U)
8
When trouble arises
Warning messageDetails/Actions
The Automatic High Beam switch was pressed
with the low beam headlights turned on.
Turn the high beam headlights on before
pressing the Automatic High Beam switch.
Indicates that, since the VSC (Vehicle Stability
Control) system was turned off, the pre-collision
brake system operation is stopped
Turn the VSC on. ( P. 255)
Indicates that the PCS (Pre-Collision System) is
temporarily unavailable
When conditions improve, the system
resumes operation. If this item is displayed
continuously, have the vehicle inspected
by your Toyota dealer.
Indicates that the PCS (Pre-Collision System) is
temporarily unavailable
When conditions improve, the system
resumes operation. If this item is displayed
continuously, have the vehicle inspected
by your Toyota dealer.
Indicates that part of the PCS (Pre-Collision Sys-
tem) sensor is dirty, covered with ice, etc.
Remove any dirt, ice, etc.
Hybrid battery (traction battery) inspection or
replacement time.
Have the hybrid battery (traction battery)
inspected by your Toyota dealer immedi-
ately.
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4978-2. Steps to take in an emergency
PRIUS v_OM_OM47B78U_(U)
8
When trouble arises
Shift control system malfunction A buzzer also sounds.
Have the vehicle inspected by your Toyota
dealer immediately. If not inspected, vehi-
cle systems may stop operating normally.
Shift control system communication malfunction
A buzzer also sounds.
Have the vehicle inspected by your Toyota
dealer.
• The hybrid system may not be able to start.
• May not be switched to the P position. When parking, choose a level location and
apply the parking brake securely.
• The automatically P position selection func- tion ( P. 178) may not function. Before
turning the power switch off, securely press
the P position switch, and be sure to check
that the shift position is in P by verifying the
shift position or P position switch operation
indicator lights.
• The power switch may not be able to be
turned off. In this case, the power switch
may be turned off by applying the parking
brake.
(If equipped)
Indicates a malfunction in the LED headlight sys-
temA buzzer also sounds.
Have the vehicle inspected by your Toyota
dealer.
Warning messageDetails/Actions
(Turns on or
Flashes)
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5168-2. Steps to take in an emergency
PRIUS v_OM_OM47B78U_(U)
■The compact spare tire
●The compact spare tire is identified by the label “TEMPORARY USE
ONLY” on the tire sidewall.
Use the compact spare tire temporarily, and only in an emergency.
●Make sure to check the tire inflation pressure of the compact spare tire.
( P. 543)
■After completing the tire change
The tire pressure warning system must be reset. ( P. 432)
■When using the compact spare tire
As the compact spare tire is not equipped with a tire pressure warning
valve and transmitter, low inflation pressure of the spare tire will not be
indicated by the tire pressure warning system. Also, if you replace the
compact spare tire after the tire pressure warning light comes on, the light
remains on.
■When the compact spare tire is equipped
The vehicle becomes lower when driving with the compact spare tire
compared to when driving with standard tires.
■If you have a flat front tire on a road covered with snow or ice
Install the compact spare tire on one of the rear wheels of the vehicle.
Perform the following steps and fit tire chains to the front tires:
Replace a rear tire with the compact spare tire.
Replace the flat front tire with the tire removed from the rear of the vehi-
cle.
Fit tire chains to the front tires.
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5268-2. Steps to take in an emergency
PRIUS v_OM_OM47B78U_(U)
WARNING
■Avoiding 12-volt battery fires or explosions
Observe the following precautions to prevent accidentally igniting the flam-
mable gas that may be emitted from the 12-volt battery:
●Make sure each jumper cable is connected to the correct terminal and that
it is not unintentionally in contact with any other than the intended terminal.
● Do not allow the other end of the jumper cable connected to the “+” termi-
nal to come into contact with any other parts or metal surfaces in the area,
such as brackets or unpainted metal.
● Do not allow the + and - clamps of the jumper cables to come into contact
with each other.
● Do not smoke, use matches, cigarette lighters or allow open flame near
the 12-volt battery.
■ 12-volt battery precautions
The 12-volt battery contains poisonous and corrosive acidic electrolyte,
while related parts contain lead and lead compounds. Observe the following
precautions when handling the 12-volt battery:
●When working with the 12-volt battery, always wear safety glasses and
take care not to allow any battery fluids (acid) to come into contact with
skin, clothing or the vehicle body.
● Do not lean over the 12-volt battery.
● In the event that battery fluid comes into contact with the skin or eyes,
immediately wash the affected area with water and seek medical attention.
Place a wet sponge or cloth over the affected area until medical attention
can be received.
● Always wash your hands after handling the 12-volt battery support, termi-
nals, and other battery-related parts.
● Do not allow children near the 12-volt battery.
■ 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. 429
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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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Page 532 of 607
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.
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