2023 TOYOTA PRIUS PRIME engine

5958-2. Steps to take in an emergency
8
When trouble arises
5Add coolant if necessary.
Water can be used in an emer-
gency if engine coolant is unavail-
able.
If water was added in an emer-
gency, have the vehicle inspected
at your Toyota dealer as soon as
possible.
6Start the hybrid system and
turn the air conditioning sys-
tem on to check that the radi-
ator cooling fan operates and
to check for coolant leaks
from the radiator or hoses.
The fan operates when the air con-
ditioning system is turned on imme-
diately after a cold start. Confirm
that the fan is operating by check-
ing the fan sound and air flow. If it is
difficult to check these, turn the air
conditioning system on and off
repeatedly. (The fan may not oper-
ate in freezing temperatures.)
7If the fan is not operating:
Stop the hybrid system
immediately and contact your
Toyota dealer.
If the fan is operating:
Have the vehicle inspected at
the nearest Toyota dealer.
8 Check if “Engine Coolant
Temp High Stop in a Safe
Place See Owner’s Manual” is shown on the multi-infor-
mation display.
If the message does not disappear:
Stop the hybrid system and contact
your Toyota dealer.
If the message is not displayed:
Have the vehicle inspected at the
nearest Toyota dealer.
■If “Hybrid System Over-
heated Output Power
Reduced” is shown on the
multi-information display
1 Stop the vehicle in a safe
place.
2 Stop the hybrid system and
carefully lift the hood.
3 After the hybrid system has
cooled down, inspect the
hoses and radiator core (radi-
ator) 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”
A
B

5968-2. Steps to take in an emergency
and “MIN” lines on the reser-
voir.
Reservoir
“MAX” line
“MIN” line
5 Add coolant if necessary.
Water can be used in an emer-
gency if power control unit coolant
is unavailable.
If water was added in an emer-
gency, have the vehicle inspected
at your Toyota dealer as soon as
possible.
6After stopping the hybrid sys-
tem and waiting for 5 minutes
or more, start the hybrid sys-
tem again and check for the
multi-information display.
If the message does not disappear:
Stop the hybrid system and contact
your Toyota dealer.
If the message is not displayed:
The hybrid system temperature has dropped and the vehicle may be
driven normally.
However, if the message appears
again frequently, contact your
Toyota dealer.
A
B
C
WARNING
■When inspecting under the
hood of your vehicle
Observe the following precau-
tions.
Failure to do so may result in seri-
ous injury such as burns.
●If steam is seen coming from
under the hood, do not open the
hood until the steam has sub-
sided. The engine compart-
ment may be very hot.
●After the hybrid system has
been turned off, check that the
“READY” indicator is off.
When the hybrid system is oper-
ating, the gasoline engine may
automatically start, or the cool-
ing 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 reser-
voir cap while th e hybrid system
and radiator are hot.
High temperature steam or
coolant could spray out.
NOTICE
■When adding engine/power
control unit coolant
Add coolant slowly after the
hybrid system has cooled down
sufficiently. Adding cool coolant to
a hot hybrid system too quickly
can cause damage to the hybrid
system.

6019-1. Specifications
9
Vehicle specifications
under the right-hand front seat.
This number is also on the Certi-
fication Regulation Label.■Engine number
The engine number is stamped
on the engine block as shown.
Engine
Model2.0 L 4-cylinder (M20A-FXS)
Type4-cylinder in line, 4-cycle, gasoline
Bore and stroke3.17  3.84 in. (80.5  97.6 mm)
Displacement121.3 cu.in. (1987 cm3)
Valve clearanceAutomatic adjustment
Fuel
Fuel typeUnleaded gasoline only
Octane Rating87 (Research Octane Number 91) or
higher
Fuel tank capacity (Reference)10.6 gal. (40 L, 8.8 Imp.gal.)

6029-1. Specifications
■Oil capacity (Drain and refill  reference*)
*: The engine oil capacity is a reference quantity to be used when changing
the engine oil. When actually adding the engine oil, make sure that the oil
level is between the low level ma rk and refill upper limit mark (P.506).
Warm up and turn off the hybrid syst em, wait about 5 minutes, and check
the oil level on the dipstick.
■Engine oil selection
“Toyota Genuine Motor Oil” is
used in your Toyota vehicle.
Use Toyota approved “Toyota
Genuine Motor Oil” or equiva-
lent to satisfy the following
grade and viscosity.
Oil grade:
ILSAC GF-6B multigrade engine
oil
Recommended viscosity: SAE 0W-16
SAE 0W-16 is the best choice
for good fuel economy and good
starting in cold weather.
If SAE 0W-16 is not available,
SAE 0W-20 oil may be used.
However, it must be replaced
with SAE 0W-16 at the next oil
change.
Electric motor (traction motor)
TypePermanent magnet synchronous motor
Maximum output120 kW
Maximum torque153.4 ft•lbf (208 N•m, 21.2 kgf•m)
Hybrid battery (traction battery)
TypeLithium-ion battery
Voltage3.7 V/cell
Capacity51.0 Ah
Quantity72 cells
Nominal voltage266.4 V
Lubrication system
With filter4.1 qt. (3.9 L, 3.4 Imp. qt.)
Without filter3.7 qt. (3.5 L, 3.1 Imp. qt.)

6039-1. Specifications
9
Vehicle specifications
Outside temperature
Oil viscosity (0W-16 is explained
here as an example):
• The 0W in 0W-16 indicates the characteristic of the oil
which allows cold startability.
Oils with a lower value before
the W allow for easier starting
of the engine in cold weather.
• The 16 in 0W-16 indicates the viscosity characteristic of the oil when the oil is at high tem-
perature. An oil with a higher
viscosity (one with a higher
value) may be better suited if
the vehicle is operated at high
speeds, or under extreme
load conditions.
How to read oil container label:
API registered mark is added to
some oil containers to help you
select the oil you should use.
*: The coolant capacity is the quantity of reference.
If replacement is necessary, contact your Toyota dealer.
A
Cooling system
Capacity*Gasoline engine6.4 qt. (6.1 L, 5.4 Imp. qt.)
Power control unit1.7 qt. (1.6 L, 1.4 Imp. qt.)
Coolant type
Use either of the following:
 “Toyota Super Long Life Coolant”
 Similar high-quality ethylene gly-
col-based non-silic ate, non-amine,
non-nitrite, and non-borate cool-
ant with long-life hybrid organic
acid technology
Do not use plain water alone.

6079-1. Specifications
9
Vehicle specifications
■Gasoline quality
In very few cases, driveability prob-
lems may be caused by the brand of
gasoline you are usin g. If driveability
problems persist, try changing the
brand of gasoline. If this does not
correct the problem, consult your
Toyota dealer.
■Recommendation of the use of
gasoline containing detergent
additives
●Toyota recommends the use of
gasoline that contains detergent
additives to avoid the build-up of
engine deposits.
●All gasoline sold in the U.S.A. con-
tains minimum detergent additives
to clean and/or keep clean intake
systems, per EPA’s lowest addi-
tives concentration program.
●Toyota strongly recommends the
use of Top Tier Detergent Gaso-
line. For more information on Top
Tier Detergent Gasoline and a list
of marketers, please go to the offi-
cial website www.toptiergas.com.
■Recommendation of the use of
low emissions gasoline
Gasolines containing oxygenates
such as ethers and ethanol, as well
as reformulated gasolines, are avail-
able in some cities. These fuels are
typically acceptable for use, provid-
ing they meet other fuel require-
ments.
Toyota recommends these fuels,
since the formulations allow for
reduced vehicle emissions.
■Non-recommendation of the
use of blended gasoline
●Use only gasoline containing up to
15% ethanol.
DO NOT use any flex-fuel or gas-
oline that could contain more than
15% ethanol, including from any
pump labeled E30 (30% ethanol
), E50 (50% ethanol ), E85
(85% ethanol ) (which are only
some examples of fuel containing
more than 15% ethanol).
●If you use gasohol in your vehicle,
be sure that it has an octane rat-
ing no lower than 87.
●Toyota does not recommend the
use of gasoline containing metha-
nol.
■Non-recommendation of the
use of gasoline containing MMT
Some gasoline contains an octane
enhancing additive called MMT
(Methylcyclopentadienyl Manga-
nese Tricarbonyl).
Toyota does not recommend the
use of gasoline that contains MMT.
Fuel information
You must only use unleaded
gasoline in your vehicle.
Select octane rating 87
(Research Octane Number
91) or higher. Use of
unleaded gasoline with an
octane rating lower than 87
may result in engine knock-
ing. Persistent knocking
can lead to engine damage.
At minimum, the gasoline you
use should meet the specifica-
tions of ASTM D4814 in the
U.S.A..
AB
C

6089-1. Specifications
If fuel containing MMT is used, your
emission control system may be
adversely affected.
The malfunction indicator lamp on
the instrument cluster may come on.
If this happens, contact your Toyota
dealer for service.
■If your engine knocks
●Consult your Toyota dealer.
●You may occasionally notice light
knocking for a short time while
accelerating or driving uphill. This
is normal and there is no need for
concern.
NOTICE
■Notice on fuel quality
●Do not use improper fuels. If
improper fuels are used, the
engine will be damaged.
●Do not use leaded gasoline.
Leaded gasoline can cause
damage to your vehicle’s three-
way catalytic converters caus-
ing the emission control system
to malfunction.
●Do not use gasohol other than
the type previously stated.
Other gasohol may cause fuel
system damage or vehicle per-
formance problems.
●Using unleaded gasoline with
an octane number or rating
lower than the level previously
stated will cause persistent
heavy knocking.
At worst, this will lead to engine
damage.
■Fuel-related poor driveability
If poor driveability (poor hot start-
ing, vaporization, engine knock-
ing, etc.) is encountered after
using a different type of fuel, dis-
continue the use of that type of
fuel.
■When refueling with gasohol
Take care not to spill gasohol. It
can damage your vehicle’s paint.
■Notice about fuel
 P.86

6139-1. Specifications
9
Vehicle specifications
Glossary of tire terminology
Tire related termMeaning
Cold tire inflation pres-
sureTire pressure when the vehicle has been parked
for three hours or more, or has not been driven
more than 1 mile or 1.5 km under that condition
Maximum inflation pres-
sureThe maximum cold inflated pressure to which a
tire may be inflated, shown on the sidewall of
the tire
Recommended inflation
pressureCold tire inflation pressure recommended by a
manufacturer
Accessory weight
The combined weight (in excess of those stan-
dard items which may be replaced) of hybrid
transmission, power steering, power brakes,
power windows, power seat s, radio and heater,
to the extent that these items are available as
factory-installed equipment (whether installed or
not)
Curb weight
The weight of a motor vehicle with standard
equipment, including the maximum capacity of
fuel, oil and coolant, and if so equipped, air con-
ditioning and additional weight optional engine
Maximum loaded vehicle
weight
The sum of:
(a) Curb weight
(b) Accessory weight
(c) Vehicle capacity weight
(d) Production options weight
Normal occupant weight
150 lb. (68 kg) times the number of occupants
specified in the second column of Table 1
* that
follows
Occupant distributionDistribution of occupants in a vehicle as speci-
fied in the third column of Table 1
* below
Production options weight
The combined weight of installed regular pro-
duction options weighing over 5 lb. (2.3 kg) in
excess of the standard items which they
replace, not previously considered in curb
weight or accessory weight, including heavy
duty brakes, ride levelers, roof rack, heavy duty
battery, and special trim