TOYOTA PRIUS PLUG-IN HYBRID 2021 Owners Manual

7218-2. Steps to take in an emergency
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
8
When trouble arises
■ When the tire pressure warning light comes on
Inspect the appearance of the tire to check that the tire is not punctured.
If the tire is punctured: P. 731
If the tire is not punctured:
Carry out the following procedure after the tire temperature has lowered suffi-
ciently.
● Check the tire inflation pressure and adjust to the appropriate level.
● If the warning light does not go out even after several minutes, check that
the tire inflation pressure is at the specified level and carry out initialization.
( P. 652)
The warning light may come on again if the above operations are conducted
without first allowing the tire temperature to lower sufficiently.
■ The tire pressure warning light may come on due to natural causes
The tire pressure warning light may come on due to natural causes such as
natural air leaks and tire inflation pressure changes caused by temperature.
In this case, adjusting the tire inflation pressure will turn off the warning light
(after a few minutes).
■ Conditions that the tire pressure warning system may not function prop-
erly
 P. 654
■ If the tire pressure warning light frequently comes on after blinking for
1minute
If the tire pressure warning light frequently comes on after blinking for
1 minute when the power switch is turned to ON mode, have it checked by
any authorized Toyota retailer or Toyota authorized repairer, or any reliable
repairer.
■ Warning buzzer
In some cases, the buzzer may not be heard due to being in a noisy location
or audio sound.

7228-2. Steps to take in an emergency
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
WARNING
■When the electric power steering system warning light comes on
When the light comes on yellow, the assist to the power steering is
restricted. When the light comes on red, the assist to the power steering is
lost and handling operations of the steering wheel become extremely
heavy. When steering wheel operations are heavier than usual, grip the
steering wheel firmly and operate it using more force than usual.
■ If the tire pressure warning light comes on
Be sure to observe the following precautions. Failure to do so could cause a
loss of vehicle control and result in death or serious injury.
● Stop your vehicle in a safe place as soon as possible. Adjust the tire infla-
tion pressure immediately.
● If the tire pressure warning light comes on even after tire inflation pressure
adjustment, it is probable that you have a flat tire. Check the tires. If a tire
is flat, repair the flat tire by us ing emergency tire puncture repair kit.
● Avoid abrupt maneuvering and braking. If the vehicle tires deteriorate, you
could lose control of the steering wheel or the brakes.
■ If a blowout or sudden air leakage should occur
The tire pressure warning system may not activate immediately.
NOTICE
■ To ensure the tire pressure warning system operates properly
Do not install tires with different specif ications or makers, as the tire pres-
sure warning system may not operate properly.

7238-2. Steps to take in an emergency
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
8
When trouble arises
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
Handling method
Follow the instructions of the mes-
sage on the multi-information dis-
play.
If any of the warning messages are shown again after the following
actions have been performed, contact any authorized Toyota retailer
or Toyota authorized repairer, or any reliable repairer.
*: The master warning light may not come on or flash when a warning mes-
sage is displayed.
The multi-information display shows warnings of system mal-
functions, incorrectly performed operations, and messages that
indicate a need for maintenance. When a message is shown,
perform the correction procedure appropriate to the message.
When a message about charging is displayed, refer to P. 197.
1
2
3

7248-2. Steps to take in an emergency
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
The warning lights and warning buzzers operate as follows depending
on the content of the message. If a message indicates the need for
inspection by a dealer, have the vehicle inspected by any authorized
Toyota retailer or Toyota authorized repairer, or any reliable repairer
immediately.
The operation of the warning lights and warning buzzers may differ
from those stated. In this case, perform the correction procedure
according to the displayed message.
*: A buzzer sounds the first time a message is shown on the multi-informa-
tion display.
Messages and warnings
System
warning
light
Warning
buzzer*Warning
Comes onSounds
Indicates an important situation, such
as when a system related to driving is
malfunctioning or that danger may
result if the correction procedure is not
performed
Comes on
or flashesSounds
Indicates an important situation, such
as when the systems shown on the
multi-information display may be mal-
functioning
FlashesSounds
Indicates a situation, such as when
damage to the vehicle or danger may
result
Comes onDoes not
sound
Indicates a condition, such as mal-
function of electrical components, their
condition, or indicates the need for
maintenance
FlashesDoes not
sound
Indicates a situation, such as when an
operation has been performed incor-
rectly, or indicates how to perform an
operation correctly

7258-2. Steps to take in an emergency
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
8
When trouble arises
■ Warning messages
The warning messages explained below may differ from the actual messages
according to operation conditions and vehicle specifications.
■ System warning lights
The master warning light does not come on or flash in the following cases.
Instead, a separate system warning light will come on along with a message
or image shown on the multi-information display.
● “Antilock Brake System Malfunction Visit Your Dealer”:
The ABS warning light comes on. ( P. 715)
● “Braking Power Low Visit Your Dealer”:
The brake system warning light (yellow) will come on. ( P. 714)
● Indicates that a door is not fully closed while the vehicle is stopped.:
The Open door warning light comes on. ( P. 7 1 7 )
■ If “Visit Your Dealer” is shown
The system or part shown on the multi- information display is malfunctioning.
Have the vehicle inspected by any authorized Toyota retailer or Toyota autho-
rized repairer, or any reliable repairer.
■ If a message about an operation is shown
● If a message about an operation of the accelerator pedal or brake pedal is
shown
• A warning message about an operation of the brake pedal may be shown
while the driving assist systems such as PCS (Pre-Collision System) or
the dynamic radar cruise control with full-speed range is operating. If a
warning message is shown, be sure to decelerate the vehicle or follow an
instruction shown on the multi-information display.
• A warning message is shown when Brake Override System operates.
( P. 360, 729)
• A warning message is shown when Drive-Start Control or Parking Sup-
port Brake function (if equipped) operates ( P. 360, 516). Follow the
instructions on the multi-information display.
● If a message about an operation of the power switch is shown
An instruction for operation of the power switch is shown when the incorrect
procedure for starting the hybrid system is performed or the power switch is
operated incorrectly. Follow the instructions shown on the multi-information
display to operate the power switch again.
● If a message about a shift operation is shown
To prevent the shift position from being selected incorrectly or the vehicle
from moving unexpectedly, the shift position may be changed automatically
( P. 381) or shift operation may be required. In this case, change the shift
position following the instructions on the multi-information display.

7268-2. Steps to take in an emergency
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
●If a message or image about an open/close state of a part or replenishment
of a consumable is shown
Confirm the part indicated by the multi-information display or a warning light,
and then perform the coping method such as closing the open door or
replenishing a consumable.
■ If “See Owner’s Manual” is shown
● If “Braking Power Low Stop in a Safe Place See Owner’s Manual” is shown,
this may be a malfunction. Immediately stop the vehicle in a safe place and
contact any authorized Toyota retailer or Toyota authorized repairer, or any
reliable repairer. Continuing to drive the vehicle may be dangerous.
● If “Engine Oil Pressure Low” is shown, this may be a malfunction. Immedi-
ately stop the vehicle in a safe place and contact any authorized Toyota
retailer or Toyota authorized repairer, or any reliable repairer.
● If the following messages are shown, there may be a malfunction. Immedi-
ately have the vehicle inspected by any authorized Toyota retailer or Toyota
authorized repairer, or any reliable repairer.
• “Plug-in charging system malfunction.”
• “Hybrid System Malfunction”
• “Check Engine”
• “Hybrid Battery System Malfunction”
• “Accelerator System Malfunction”
• “Smart Entry & Start System Malfunction See Owner’s Manual”
● If “Exhaust Filter Full See Owner’s Manual” is shown on the multi-informa-
tion display is shown, follow the instruction. ( P. 5 5 8 )
■ If “Shift System Not Active Apply Parking Brake Securely While Parking
See Owner’s Manual” is shown
Indicates a temporary operation failure or malfunction in the shift control sys-
tem. Immediately have the vehicle inspected by any authorized Toyota
retailer or Toyota authorized repairer, or any reliable repairer.
When the message is shown, the hybrid system may not be started or the
shift position may not be changed normally. (Coping method: P. 729)
■ If “Shift System Malfunction Apply Parking Brake Securely While Park-
ing See Owner’s Manual” is shown
Indicates a malfunction in the shift control system. Immediately have the vehi-
cle inspected by any authorized Toyota retailer or Toyota authorized repairer,
or any reliable repairer.
When the message is shown, the hybrid system may not be started or the
shift position may not be changed normally. (Coping method: P. 729)

7278-2. Steps to take in an emergency
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
8
When trouble arises
■ If “ Switch Malfunction Apply Parking Brake Securely While Parking
See Owner’s Manual” is shown
The P position switch may not operate. Immediately have the vehicle
inspected by any authorized Toyota retailer or Toyota authorized repairer, or
any reliable repairer.
When parking the vehicle, stop the vehicle on level ground and apply the
parking brake firmly.
■ If “Shift System Malfunction Shifting Unavailable See Owner’s Manual”
is shown
Indicates a malfunction in the shift control system. Immediately have the vehi-
cle inspected by any authorized Toyota retailer or Toyota authorized repairer,
or any reliable repairer.
The shift position may not be shifted from P to other than P.
■ If “Shift System Malfunction Stop in a Safe Place See Owner’s Manual”
is shown
Indicates a malfunction in the shift control system. Immediately have the vehi-
cle inspected by any authorized Toyota retailer or Toyota authorized repairer,
or any reliable repairer.
The shift position may not be changed. Stop the vehicle in a safe place.
■ 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 any authorized Toyota retailer or Toyota authorized repairer,
or any reliable repairer.
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. 729)
● 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. 755)
■ If “Hybrid System Overheated. Reduced 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. 761

7288-2. Steps to take in an emergency
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
■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. 623.
● When the air intake vents or filters are not dirty and the warning message is
shown, have the vehicle inspected at any authorized Toyota retailer or
Toyota authorized repairer, or any reliable repairer.
■ If “Traction Battery Needs to be Protected Refrain From the Use of
Position” is shown
This message may be displayed when the shift position is in N.
As the hybrid battery (traction battery) can not be charged when the shift
position is in N, shift the shift position to P when the vehicle is stopped.
■ If “Traction Battery Needs to be Protected Shift into to Restart” is
shown
This message is displayed when the hybrid battery (traction battery) charge
has become extremely low because the vehicle has been left with the N shift
position selected for a certain amount of time.
When operating the vehicle, shift to P and restart the hybrid system.
■ If “Shift to Before Exiting Vehicle” is shown
Message is displayed when the driver’s door is opened without turning the
power switch to off with the shift position in any position other than P.
Shift the shift position to P.
■ If “Shift is in Release Accelerator Before Shifting” is shown
Message is displayed when the accelerator pedal has been depressed and
the shift position is in N.
Release the accelerator pedal and shift the shift position to D or R.
■ If “Depress Brake When Vehicle is Stopped. Hybrid System may Over-
heat.” is shown
The message may be shown when the accelerator pedal is depressed to hold
the vehicle while the vehicle is stopped on an uphill, etc.
The hybrid system may overheat. Release the accelerator pedal and depress
the brake pedal.
■ If “Shifted to Stop Vehicle to Shift to ” is shown
If the P position switch is pressed while driving, the shift position is changed
to N and the message is shown. ( P. 381)
■ If “Auto Power OFF to Conserve Battery” is shown
The power switch has been turned off by the automatic power off function.
When starting the hybrid system next time, operate the hybrid system for
approximately 5 minutes to recharge the 12-volt battery.

7298-2. Steps to take in an emergency
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
8
When trouble arises
■ If “Engine Oil Level Low Add or Replace” is displayed
The engine oil level may be low. Check the level of the engine oil, and add
engine oil if necessary. This message may be displayed if the vehicle is
stopped on a slope. Move the vehicle to a level surface and check if the mes-
sage disappears.
■ If “Accelerator and Brake Pedals Pressed Simultaneously” is shown
The accelerator and brake pedals are being depressed simultaneously.
( P. 360)
Release the accelerator pedal and depress the brake pedal.
■ If a message that indicates the malfunction of front camera is displayed
The following systems may be suspended until the problem shown in the
message is resolved. ( P. 416, 714)
● PCS (Pre-Collision System)
● LTA (Lane Tracing Assist)
● AHS (Adaptive High-beam System)
● RSA (Road Sign Assist)
● Dynamic radar cruise control with full-speed range
■ If “Radar Cruise Control Unavailable See Owner’s Manual” is shown
The dynamic radar cruise control with full-speed range system is suspended
temporarily or until the problem show n in the message is resolved. (causes
and coping methods: P. 416)
■ If “Radar Cruise Control Unavailable” is shown
The dynamic radar cruise control with full-speed range system cannot be
used temporarily. Use the system when it becomes available again.
■ If the shift position cannot be changed or the power switch is turned to
ACCESSORY mode even if trying to turn the power switch off when a
warning message is shown
If the 12-volt battery is discharged or the shift control system is malfunction-
ing, the followings may occur.
● The shift position may not be changed to P.
When parking, stop the vehicle on level ground and apply the parking brake
firmly.
● The hybrid system may not start.
● The power switch may be turned to ACCESSORY mode even if trying to
turn the power switch off.
In this case, the power switch may be turned off after applying the parking
brake.
● The automatic P position selection function (P. 382) may not operate.
Before turning the power switch off, be sure to press the P position switch
and check that the shift position is in P by the shift position indicator or P
position switch indicator.

7308-2. Steps to take in an emergency
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
■Warning buzzer
 P. 721
NOTICE
■If “Have Traction Battery Inspected” is shown
The hybrid battery (traction battery) is scheduled to be inspected or
replaced. Have the vehicle inspected by any authorized Toyota retailer or
Toyota authorized repairer, or any reliable repairer immediately.
● Continuing to drive the vehicle without having the hybrid battery (traction
battery) inspected will cause the hybrid system not to start.
● If the hybrid system does not start, contact any authorized Toyota retailer
or Toyota authorized repairer, or any reliable repairer immediately.