engine TOYOTA PRIUS PRIME 2023 Repair Manual

5728-2. Steps to take in an emergency
●LDA (Lane Departure Alert)
●LTA (Lane Tracing Assist)
● LCA (Lane Change Assist) (if
equipped)
●AHB (Automatic High Beam)
●Dynamic radar cruise control
●PDA (Proactive Driving Assist)
Follow the following correction
methods.
• Check if there is any foreign mat- ter attached to the radar sensor or
radar sensor cover and clean
them if necessary ( P.286)
• The radar sensor may be mis-
aligned and will be adjusted auto-
matically while driving. Continue
driving for a while.
■If “Unavailable Activation Con-
dition not Satisfied See Owner’s
Manual” is displayed
The LCA function cannot be
used as the operating conditions
have not been met.
Operate the turn signal lever again
after all of the op erating conditions
are met.
■If “Cruise Control Unavailable
See Owner’s Manual” is dis-
played
Indicates one of the following sys-
tems is disabled.
●Dynamic radar cruise control
●Cruise control
A message is displayed when the
driving assist switch is pushed
repeatedly.
Press the driving assist switch
quickly and firmly.
■If “Driver Monitor Out of Tem-
perature Range Wait until Nor-
mal Temperature” is displayed
Indicates one of the following sys-
tems is disabled.
●Driver monitor (if equipped)
●Traffic Jam Assist (if equipped)
The temperature of the driver moni-
tor camera is outside of the operat-
ing range. Wait for the temperature
to become appropriate.
■If “Driver Monitor Unavailable
See Owner’s Manual” is dis-
played
The lens of the driver monitor cam-
era may be dirty.
When there is dirt on the camera
lens, clean it with a dry, soft cloth so
as to not damage it.
■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.
(  P.506) 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 “Maintenance Required
Soon” is shown
Indicates that all maintenance
according to the driven distance on
the maintenance 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
maintenance is performed.
(  P.495)
*: Refer to the separate “Scheduled
Maintenance Guide” or “Owner’
Manual Supplement” for the main-
tenance interval applicable to your
vehicle.
■If “Maintenance Required Visit
Your Dealer” is shown
Indicates that all maintenance is
required to correspond to the driven

5738-2. Steps to take in an emergency
8
When trouble arises
distance on the maintenance sched-
ule*.
Comes on approximately 5000
miles (8000 km) after the message
has been reset. (The indicator will
not work properly unless the mes-
sage has been reset.)
Perform the necessary mainte-
nance. Please reset the message
after the maintenance is performed.
(  P.495)
*: Refer to the separate “Scheduled
Maintenance Guide” or “Owner’
Manual Supplement” for the main-
tenance interval applicable to your
vehicle.
■If “Engine Maintenance
Required Visit Your Dealer” is
shown
The engine or an engine component
is malfunctioning. Have the vehicle
inspected by your Toyota dealer
immediately.
■If “Oil Maintenance Required
Soon” is displayed
Indicates that the engine oil should
be scheduled to be changed.
Check the engine oil and change it if
necessary.
After changing the engine oil, make
sure to reset the message.
(  P.506)
■If “Oil Maintenance Required
Visit Your Dealer” is displayed
Indicates that the engine oil should
be changed.
Check and change the engine oil,
and oil filter by your Toyota dealer.
After changing the engine oil, make
sure to reset the message.
(  P.506)
■If “Accelerator and Brake Ped-
als Pressed Simultaneously” is
shown
The accelerator and brake pedals
are being depressed simultane-
ously. ( P.240) Release the accelerator pedal and
depress the brake pedal.
■Warning buzzer
 P.563
WARNING
■If a warning light comes on or
a warning buzzer sounds
when a warning message is
shown on the multi-informa-
tion display
 P.564
NOTICE
■If “Maintenance Required For
Traction Battery At Your
Dealer” is shown
The hybrid battery (traction bat-
tery) 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 bat-
tery (traction battery) inspected
will cause the hybrid system not
to start.
●If the hybrid system does not
start, contact your Toyota
dealer immediately.

5908-2. Steps to take in an emergency
point.
Exclusive jump starting terminal (your vehicle)
Positive (+) battery terminal (second vehicle)
Negative (-) battery terminal (second vehicle)
Metallic point shown in the illustration
4 Start the engine of the sec-
ond vehicle. Increase the
engine speed slightly and
maintain at that level for
approximately 5 minutes to
recharge the 12-volt battery
of your vehicle.
5 Maintain the engine speed of
the second vehicle and start
the hybrid system of your
vehicle by turning the power
switch to ON.
6 Make sure the “READY” indi-
cator comes on. If the indica-
tor light does not come on,
contact your Toyota dealer.
7 Once the hybrid system has
started, remove the jumper
cables in the exact reverse order from which they were
connected.
8 Close the exclusive jump
starting terminal cover, and
reinstall the fuse box cover to
its original position.
Once the hybrid system starts,
have the vehicle inspected at
your Toyota dealer as soon as
possible.
■Starting the hybrid system
when the 12-volt battery is dis-
charged
The hybrid system cannot be
started by push-starting.
■To prevent 12-volt battery dis-
charge
●Turn off the headlights and the
audio system while the hybrid sys-
tem is off.
●Turn off any unnecessary electri-
A
B
C
D

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

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