Toyota Prius Prime (2020 year). Owner's manual — part 42

664

8-2. Steps to take in an emergency

High coolant temperature warning light

• When the light flashes:

Indicates that the engine coolant temperature is too high
The light changes from a flashing to a solid light when
the temperature further increases

 Immediately stop the vehicle in a safe place. (P. 709)

• When the light comes on without flashing:

Indicates a malfunction in the exhaust heat recirculator
system

 Have the vehicle inspected by your Toyota dealer

immediately.

(Flashes)

(If equipped)

PKSB OFF indicator

Indicates a malfunction in the Parking Support Brake func-
tion

 Have the vehicle inspected by your Toyota dealer.

The warning light will operate as follows, even when the
system is not malfunctioning:
• The light will come on when the Parking Support Brake

function is turned off (

P. 444)

• The light will come on when the Parking Support Brake

function is operating (

P. 448)

• The light will flash when the system cannot be temporar-

ily used (

P. 452)

Open door warning light (warning buzzer)

*

3

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 1.7 gal.
(6.4 L, 1.4 Imp.gal.) or less

 Refuel the vehicle.

Driver’s and front passenger’s seat belt reminder light
(warning buzzer)

*

4, 5

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.

Warning light

Warning light/Details/Actions

665

8-2. Steps to take in an emergency

8

Wh
en tro

uble

a

ris

es

(U.S.A.)

(Canada)

Rear passengers’ seat belt reminder light (warning
buzzer)

*

6

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. 672

Tire pressure warning light

When the light comes on:

Low tire inflation pressure such as

• Natural causes (

P. 668)

• Flat tire (

P. 680)

 Adjust the tire inflation pressure to the specified

level.

The light will turn off after a few minutes. In case

the light does not turn off even if the tire inflation

pressure is adjusted, have the system checked by

your Toyota dealer.

When the light comes on after blinking for 1 minute:

Malfunction in the tire pressure warning system

(

P. 669)

 Have the system checked by your Toyota dealer.

Warning light

Warning light/Details/Actions

666

8-2. Steps to take in an emergency

Brake Override System/Drive-Start Control/
Parking Support Brake function (symbol display)

*

7

Brake Override System

Indicates that the accelerator and brake pedals are being
depressed simultaneously, and the Brake Override Sys-
tem is operating

 Release the accelerator pedal and depress the brake

pedal.

Indicates a malfunction in the Brake Override System
(with warning buzzer)

 Have the vehicle inspected by your Toyota dealer

immediately.

Drive-Start Control

Indicates that the shift position was changed and Drive-
Start Control was operated while depressing the accelera-
tor pedal (with warning buzzer)

 Momentarily release the accelerator pedal.

Indicates a malfunction in the Drive-Start Control system
(with warning buzzer)

 Have the vehicle inspected by your Toyota dealer

immediately.

Parking Support Brake function

Indicates that the Parking Support Brake function (if
equipped) is operating (

P. 448)

 Follow the instruction that is displayed on the multi-

information display.

(Canada only)

Low engine oil pressure warning (symbol display)

*

7

Indicates that the engine oil pressure is too low

 Immediately stop the vehicle in a safe place and con-

tact your Toyota dealer.

Warning light

Warning light/Details/Actions

667

8-2. Steps to take in an emergency

8

Wh
en tro

uble

a

ris

es

*

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.

*

2

: Low engine oil pressure warning buzzer:

A buzzer also sounds continuously for approximately 30 seconds at maxi-
mum in addition to the low engine oil pressure warning light when the
“READY” indicator is illuminated.

*

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 3 mph [5 km/h]).

*

4

: Driver’s seat belt warning buzzer:

The driver’s seat belt warning buzzer sounds to alert the driver that his or
her seat belt is not fastened. Once the power switch is turned to ON mode,
the buzzer sounds for 6 seconds. If the vehicle reaches a speed of 12 mph
(20 km/h), the buzzer sounds once. If the seat belt is still unfastened after
24 seconds, the buzzer will sound intermittently for 6 seconds. Then, if the
seat belt is still unfastened, the buzzer will sound in a different tone for 90
more seconds.

*

5

: Front passenger’s seat belt warning buzzer:

The front passenger’s seat belt warning buzzer sounds to alert the front
passenger that his or her seat belt is not fastened. The buzzer sounds
once if the vehicle reaches a speed of 12 mph (20 km/h). If the seat belt is
still unfastened after 24 seconds, the buzzer will sound intermittently for 6
seconds. Then, if the seat belt is still unfastened, the buzzer will sound in a
different tone for 90 more seconds.

*

6

: Rear passengers’ seat belt warning buzzer:

The rear passengers’ seat belt warning buzzer sounds to alert the rear
passengers that his or her seat belt is not fastened. The buzzer sounds
intermittently for 6 seconds after the vehicle reaches a speed of 12 mph
(20 km/h). Then, if the seat belt is still unfastened, the buzzer will sound in
a different tone for 24 more seconds.

*

7

: This symbol is displayed on the multi-information display.

668

8-2. Steps to take in an emergency

■

SRS warning light
This warning light system monitors the airbag sensor assembly, front impact
sensors, side impact sensors (front door), side impact sensors (rear), driver’s
seat belt buckle switch, front passenger occupant classification system (ECU
and sensors), “AIR BAG ON” indicator light, “AIR BAG OFF” indicator light,
front passenger’s seat belt buckle switch, seat belt pretensioners, airbags,
interconnecting wiring and power sources. (

P. 36)

■

Front passenger detection sensor, seat belt reminder and warning
buzzer

●

If luggage is placed on the front passenger seat, the front passenger detec-
tion sensor may cause the warning light to flash and the warning buzzer to
sound even if a passenger is not sitting in the seat.

●

If a cushion is placed on the seat, the sensor may not detect a passenger,
and the warning light may not operate properly.

■

Electric power steering system warning light (warning buzzer)
When the 12-volt battery charge becomes insufficient or the voltage tempo-
rarily drops, the electric power steering system warning light may come on
and the warning buzzer may sound.

■

If the malfunction indicator lamp comes on while driving
First check the following:

●

Is the fuel tank empty?
If it is, fill the fuel tank immediately.

●

Is the fuel tank cap loose?
If it is, tighten it securely.

The malfunction indicator lamp will go off after several driving trips.
If the malfunction indicator lamp does not go off even after several trips, con-
tact your Toyota dealer as soon as possible.

■

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. 680

If the tire is not punctured:
Check the tire inflation pressure and adjust to the appropriate level. Initial-

izing the tire pressure warning system will not turn off the tire pressure

warning light.

■

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 tem-

perature. 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

properly
P. 607

669

8-2. Steps to take in an emergency

8

Wh
en tro

uble

a

ris

es

■

If the tire pressure warning light frequently comes on after blinking

for 1 minute
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 your Toyota dealer.

■

Warning buzzer
In some cases, the buzzer may not be heard due to being in a noisy location
or audio sound.

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

inflation pressure immediately.

●

If the tire pressure warning light comes on even after tire inflation pres-

sure adjustment, it is probable that you have a flat tire. Check the tires.

If a tire is flat, repair the flat tire by using 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.

670

8-2. Steps to take in an emergency

WARNING

■

Maintenance of the tires
Each tire, including the spare (if provided), should be checked monthly

when cold and inflated to the inflation pressure recommended by the

vehicle manufacturer on the vehicle placard or tire inflation pressure

label (tire and load information label). (If your vehicle has tires of a dif-

ferent size than the size indicated on the vehicle placard or tire inflation

pressure label [tire and load information label], you should determine

the proper tire inflation pressure for those tires.)
As an added safety feature, your vehicle has been equipped with a tire

pressure monitoring system (TPMS-tire pressure warning system) that

illuminates a low tire pressure telltale (tire pressure warning light) when

one or more of your tires is significantly under-inflated. Accordingly,

when the low tire pressure telltale (tire pressure warning light) illumi-

nates, you should stop and check your tires as soon as possible, and

inflate them to the proper pressure. Driving on a significantly under-

inflated tire causes the tire to overheat and can lead to tire failure.

Under-inflation also reduces fuel efficiency and tire tread life, and may

affect the vehicle’s handling and stopping ability.
Please note that the TPMS (tire pressure warning system) is not a sub-

stitute for proper tire maintenance, and it is the driver’s responsibility to

maintain correct tire pressure, even if under-inflation has not reached

the level to trigger illumination of the TPMS low tire pressure telltale (tire

pressure warning light).
Your vehicle has also been equipped with a TPMS (tire pressure warn-

ing system) malfunction indicator to indicate when the system is not

operating properly. The TPMS (tire pressure warning system) malfunc-

tion indicator is combined with the low tire pressure telltale (tire pressure

warning light). When the system detects a malfunction, the telltale will

flash for approximately one minute and then remain continuously illumi-

nated. This sequence will continue upon subsequent vehicle start-ups

as long as the malfunction exists. When the malfunction indicator is illu-

minated, the system may not be able to detect or signal low tire pres-

sure as intended.
TPMS (tire pressure warning system) malfunctions may occur for a vari-

ety of reasons, including the installation of replacement or alternate tires

or wheels on the vehicle that prevent the TPMS (tire pressure warning

system) from functioning properly. Always check the TPMS (tire pres-

sure warning system) malfunction telltale after replacing one or more

tires or wheels on your vehicle to ensure that the replacement or alter-

nate tires and wheels allow the TPMS (tire pressure warning system) to

continue to function properly.

671

8-2. Steps to take in an emergency

8

Wh
en tro

uble

a

ris

es

NOTICE

■

To ensure the tire pressure warning system operates properly
Do not install tires with different specifications or makers, as the tire

pressure warning system may not operate properly.

672

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
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 your Toyota dealer.

*

: 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. 185.

1

2
3

673

8-2. Steps to take in an emergency

8

Wh
en tro

uble

a

ris

es

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 your Toyota
dealer 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 flashes

Sounds

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

674

8-2. Steps to take in an emergency

■

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. 663)

●

“Braking Power Low Visit Your Dealer”:
The brake system warning light (yellow) will come on. (

P. 662)

●

Indicates that a door is not fully closed while the vehicle is stopped.:
The Open door warning light comes on. (

P. 664)

■

If “Visit Your Dealer” is shown
The system or part shown on the multi-information display is malfunctioning.
Have the vehicle inspected by your Toyota dealer.

■

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 Drive-Start Control, Brake Override Sys-
tem or Parking Support Brake function (if equipped) operates (

P. 320,

448). 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. 344) or shift operation may be required. In this case, change the shift

position following the instructions on the multi-information display.

●

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.

675

8-2. Steps to take in an emergency

8

Wh
en tro

uble

a

ris

es

■

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 your Toyota dealer. Continuing to drive the vehicle may be danger-
ous.

●

If “Engine Oil Pressure Low” is shown, this may be a malfunction. Immedi-
ately stop the vehicle in a safe place and contact your Toyota dealer.

●

If the following messages are shown, there may be a malfunction. Immedi-
ately have the vehicle inspected by your Toyota dealer.
• “Plug-in charging system malfunction.”
• “Hybrid System Malfunction”
• “Check Engine”
• “Hybrid Battery System Malfunction”
• “Accelerator System Malfunction”
• “Smart Key System Malfunction See Owner’s Manual”

■

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 your Toyota dealer.
When the message is shown, the hybrid system may not be started or the
shift position may not be changed normally. (Coping method:

P. 678)

■

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 your Toyota dealer.
When the message is shown, the hybrid system may not be started or the
shift position may not be changed normally. (Coping method:

P. 678)

■

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 your Toyota dealer.
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 your Toyota dealer.
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 your Toyota dealer.
The shift position may not be changed. Stop the vehicle in a safe place.

676

8-2. Steps to take in an emergency

■

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 your Toyota dealer.
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. 678)

●

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. 703)

■

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. 709

■

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. 570.

●

When the air intake vents or filters are not dirty and the warning message is
shown, have the vehicle inspected at your Toyota dealer.

■

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.

677

8-2. Steps to take in an emergency

8

Wh
en tro

uble

a

ris

es

■

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. 344)

■

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.

■

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 Depressed Simultaneously” is shown
The accelerator and brake pedals are being depressed simultaneously.
(

P. 320)

Release the accelerator pedal and depress the brake pedal.

■

If “Front Camera Unavailable See Owner’s Manual” or “Front Camera
Unavailable” is displayed.
The following systems may be suspended until the problem shown in the
message is resolved. (

P. 392, 662)

●

PCS (Pre-Collision System)

●

LDA (Lane Departure Alert with steering control)

●

Dynamic radar cruise control with full-speed range

●

Automatic High Beam

678

8-2. Steps to take in an emergency

■

If “Cruise Control not Available” 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 “Maintenance Required Soon” is displayed (U.S.A. only)
Indicates that all maintenance according to the driven distance on the mainte-
nance schedule

*

should be performed soon.

Comes on approximately 4500 miles (7200 km) after the message has been
reset.
If necessary, perform maintenance. Please reset the message after the main-
tenance is performed. (

P. 576)

*

: Refer to the separate “Scheduled Maintenance Guide” or “Owner’s Manual

Supplement” for the maintenance interval applicable to your vehicle.

■

If “Maintenance Required Visit Your Dealer” is displayed (U.S.A. only)
Indicates that all maintenance is required to correspond to the driven distance
on the maintenance schedule

*

.

Comes on approximately 5000 miles (8000 km) after the message has been
reset. (The indicator will not work properly unless the message has been
reset.)
Perform the necessary maintenance. Please reset the message after the
maintenance is performed. (

P. 576)

*

: Refer to the separate “Scheduled Maintenance Guide” or “Owner’s Manual

Supplement” for the maintenance interval applicable to your vehicle.

■

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. 345) 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.

■

Warning buzzer
P. 669

679

8-2. Steps to take in an emergency

8

Wh
en tro

uble

a

ris

es

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 your Toyota dealer 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 your Toyota dealer immedi-
ately.