2023 TOYOTA PRIUS PRIME engine coolant

5047-3. Do-it-yourself maintenance
Engine oil filler cap (P.506)
Engine oil level dipstick ( P.504)
Brake fluid reservoir ( P.509)
Fuse boxes ( P.540)
Washer fluid tank ( P.510)
Radiator ( P.508)
Electric cooling fan
Condenser ( P.508)
Power control unit coolant reservoir ( P.507)
Engine coolant reservoir ( P.507)
■12-volt battery
 P.511
With the engine at operating
temperature and turned off,
check the oil level on the dip-
Engine compartment
Components
A
B
C
D
E
F
G
H
I
J
Checking the engine oil

5077-3. Do-it-yourself maintenance
7
Maintenance and care
The coolant level is satisfactory
if it is between the “MAX” and
“MIN” lines on the reservoir
when the hybrid system is cold.
■Engine coolant reservoirReservoir cap
“MAX” line
“MIN” line
If the level is on or below the “MIN”
line, add coolant up to the “MAX”
line. ( P.594)
■Power control unit coolant
reservoir
Reservoir cap
“MAX” line
“MIN” line
If the level is on or below the “MIN”
line, add coolant up to the “MAX”
WARNING
■Used engine oil
●Used engine oil contains poten-
tially harmful contaminants
which may cause skin disorders
such as inflammation and skin
cancer, so care should be taken
to avoid prolonged and
repeated contact. To remove
used engine oil from your skin,
wash thoroughly with soap and
water.
●Dispose of used oil and filters
only in a safe and acceptable
manner. Do not dispose of used
oil and filters in household trash,
in sewers or onto the ground.
Call your Toyota dealer, service
station or auto parts store for
information concerning recy-
cling or disposal.
●Do not leave used engine oil
within the reach of children.
NOTICE
■When replacing the engine oil
●Be careful not to spill engine oil
on the vehicle components.
●Avoid overfilling, or the engine
could be damaged.
●Check the oil level on the dip-
stick every time you refill the
vehicle.
●Be sure the engine oil filler cap
is properly tightened.
■If oil is spilled on the engine
cover
To prevent the engine cover from
being damaged, remove any
engine oil from the engine cover
as soon as possible using a neu-
tral detergent. Do not use an
organic solvent such as brake
cleaner.
Checking the coolant
A
B
C
A
B
C

5087-3. Do-it-yourself maintenance
line. (P.595)
■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.
U.S.A.:
“Toyota Super Long Life Coolant” is
a mixture of 50% coolant and 50%
deionized water. (Minimum tem-
perature: -31°F [-35°C])
Canada:
“Toyota Super Long Life Coolant” is
a mixture of 55% coolant and 45%
deionized water. (Minimum tem-
perature: -44°F [-42°C])
For more details about coolant, con-
tact your Toyota dealer.
■If the coolant level drops within
a short time of replenishing
Visually check the radiators, 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 sys-
tem.
Check the radiator and con-
denser, and clear away any for-
eign 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.
WARNING
■When the hybrid system is
hot
Do not remove the engine/power
control unit coolant reservoir caps
or the radiator cap.
The cooling system may be under
pressure and may spray hot cool-
ant 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.
Checking the radiator and
condenser
WARNING
■When the hybrid system is
hot
Do not touch the radiator or con-
denser as they may be hot and
cause serious injuries, such as
burns.

5097-3. Do-it-yourself maintenance
7
Maintenance and care
■Checking fluid level
The brake fluid level should be
between the “MAX” and “MIN”
lines on the tank.
■Adding fluid
1 Slide and lift up the rubber
strip to partly remove it, and then remove the clip remove
it as shown in the illustration.
2 Disconnect the claws and
remove the service cover.
3 Remove the reservoir cap.
4 Add brake fluid slowly while
checking the fluid level.
Make sure to check the fluid
type and prepare the necessary
WARNING
■When the electric cooling fan
is operating
Do not touch the engine compart-
ment.
With the power switch in ON, the
electric cooling fan may automati-
cally start to run if the air condi-
tioning is on and/or the coolant
temperature is high. Be sure the
power switch is OFF when work-
ing near the electric cooling fan or
radiator grille.
Checking and adding the
brake fluid

5548-2. Steps to take in an emergency
Fluid leaks under the vehicle
(Water dripping from the air
conditioning after use is nor-
mal.)
 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 think something
is wrong
If you notice any of the fol-
lowing symptoms, your
vehicle probably needs
adjustment or repair. Con-
tact your Toyota dealer as
soon as possible.
Visible symptoms
Audible symptoms
Operational symptoms

5568-2. Steps to take in an emergency
■High coolant temperature warning light (warning buzzer)
■Low engine oil pressure warning light* (warning buzzer)
*: This light illuminates on the multi-information display with a message.
■Hybrid system overheat warning light* (warning buzzer)
*: This light illuminates on the multi- information display with a message.
■Malfunction indicator lamp
Warning lightDetails/Actions
Indicates that the engine is overheating
Immediately stop the vehicle in a safe
place.
Handling method ( P.594)
Warning lightDetails/Actions
Indicates that the engine oil pressure is too low
 Immediately stop the vehicle in a safe
place and contact your Toyota dealer.
( P.506)
Warning lightDetails/Actions
Indicates that the hybrid system has overheated
 Stop the vehicle in a safe place. Handling
method ( P.595)
Warning lightDetails/Actions
(U.S.A.)
(Canada)
Indicates a malfunction in:
 The hybrid system;
 The electronic engine control system;
 The electronic throttle control system; or
 The emission control system (if equipped)
 Have the vehicle inspected by your Toyota
dealer immediately.

5688-2. Steps to take in an emergency
To prevent the shift lever from being
operated incorrectly or the vehicle
from moving unexpectedly, a mes-
sage that requires shifting the shift
position may be displayed on the
multi-information display.
In that case, follow the instruction of
the message and shift the shift posi-
tion.
●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 di splay or a warn-
ing light, and then perform the cop-
ing method such as closing the
open door or replenishing a con-
sumable.
■If a message that indicates the
need for visiting your Toyota
dealer is displayed
The system or part shown on the
multi-information di splay is malfunc-
tioning. Have the vehicle inspected
by your Toyota dealer immediately.
■If a message that indicates the
need for referring to Owner’s
Manual is displayed
●If “Engine Coolant Temp High” is
shown, follow the instructions,
accordingly. ( P.594)
●If the following messages are
shown, there may be a malfunc-
tion. Immediately have the vehi-
cle inspected by your Toyota
dealer.
• “Plug-in Charging System Mal-
function”
• “Hybrid System Malfunction”
• “Check Engine”
• “Traction battery system malfunc- tion”
• “Accelerator System Malfunction”
• “Smart Key System malfunction”
• “Shift System Malfunction Apply Parking Brake Se curely When
Parking See Owner’s Manual” • “P Switch Malfunction Apply Park-
ing Brake Securely When Parking
See Owner’s Manual”
• “Shift System Unavailable Apply Parking Brake Securely When
Parking See Owner’s Manual”
• “Shift System Malfunction See Owner’s Manual”
• “Shift System Malfunction Stop in
a Safe Place See Owner’s Man-
ual”
• “Battery Low Shifting Unavailable
See Owner’s Manual”
●If the following messages are
shown, there may be a malfunc-
tion. Immediately stop the vehicle
in a safe place and contact your
Toyota dealer. Continuing to drive
the vehicle may be dangerous.
• “Oil pressure low”
• “Braking Power Low”
●If any of the following messages
are shown on the multi-informa-
tion display, the vehicle may have
run out of fuel. Stop the vehicle in
a safe place and, if the fuel level is
low, refuel the vehicle.
• “Hybrid system stopped”
• “Engine stopped No Fuel”
●If “12-Volt Battery Charging Sys-
tem Malfunction Stop in a Safe
Place See Owner’s Manual” is
shown
Indicates a malfunction in the vehi-
cle’s charging system. Pull over and
stop the vehicle as soon as it is safe
to do so.
While the message is displayed, the
functions of the air conditioning, etc.
may be partially lim ited in order to
reduce the power consumption of
the 12-volt battery.
■If “Traction battery needs to be
protected. Refrain from the use
of N position.” is shown
This message may be displayed
when the shift position is in N.
As the hybrid battery (traction bat-
tery) can not be charged when the

5948-2. Steps to take in an emergency
■If the high coolant tempera-
ture warning light comes on
or flashes or “Engine Cool-
ant Temp High Stop in a
Safe Place See Owner’s
Manual” is shown on the
multi-information display
1 Stop the vehicle in a safe
place and turn off the air con-
ditioning system, and then
stop the hybrid system.
2 If you see steam:
Carefully lift the hood after the steam subsides.
If you do not see steam:
Carefully lift the hood.
3 After the hybrid system has
cooled down sufficiently,
inspect the hoses and radia-
tor core (radiator) for any
leaks.
Radiator
Cooling fans
If a large amount of coolant leaks,
immediately contact your Toyota
dealer.
4The coolant level is satisfac-
tory if it is between the “MAX”
and “MIN” lines on the reser-
voir.
Reservoir
“MAX” line
“MIN” line
If your vehicle over-
heats
The following may indicate
that your vehicle is over-
heating.
The high coolant tempera-
ture warning light ( P.556)
comes on or flashes, or a
loss of hybrid system power
is experienced. (For exam-
ple, the vehicle speed does
not increase.)
 “Engine Coolant Temp High
Stop in a Safe Place See
Owner’s Manual” or “Hybrid
System Overheated Output
Power Reduced” is shown
on the multi-information dis-
play.
 Steam comes out from
under the hood.
Correction procedures
A
B
A
B
C