check engine TOYOTA PRIUS PRIME 2023 Owner's Manual

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

5407-3. Do-it-yourself maintenance
1Turn the power switch off.
Confirm that the charging connec-
tor is not connected.
2Open the fuse box cover.
Engine compartment:
Push claw and to com-
pletely release the lock, and then lift
up the cover.
Left side instrument panel
Remove the lid.
Right side luggage compart-
ment
Open the deck board. ( P.454)
Hold the handle and pull it toward
you, and then the 3 clips will be dis-
engaged
3 Remove the fuse.
Only type A fuse can be removed
Checking and replac-
ing fuses
If any of the electrical com-
ponents do not operate, a
fuse may have blown. If this
happens, check and replace
the fuses as necessary.
Checking and replacing
fuses
AB

5427-3. Do-it-yourself maintenance
Adjustment bolt A
Adjustment bolt B
 Make sure the vehicle has a
full tank of gasoline and the
area around the headlight is
not deformed.
 Park the vehicle on level
ground.
 Make sure the tire inflation
pressure is at the specified
level.
 Have someone sit in the
driver’s seat.
 Bounce the vehicle several
times.
WARNING
■To prevent system break-
downs and vehicle fire
Observe the following precau-
tions.
Failure to do so may cause dam-
age to the vehicle, and possibly a
fire or injury.
●Never use a fuse of a higher
amperage rating than that indi-
cated, or use any other object in
place of a fuse.
●Always use a genuine Toyota
fuse or equivalent.
Never replace a fuse with a
wire, even as a temporary fix.
●Do not modify the fuses or fuse
boxes.
NOTICE
■Before replacing fuses
Have the cause of electrical over-
load determined and repaired by
your Toyota dealer as soon as
possible.
■To prevent damage to the
engine compartment fuse box
cover
When opening the fuse box, com-
pletely release the claw locks
before lifting up the cover. Other-
wise, the claws may be damaged.
Headlight aim
Vertical movement adjust-
ing bolts
Before checking the head-
light aim
A
B

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

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.

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.