2023 TOYOTA COROLLA HYBRID cooling

3186-3. Do-it-yourself maintenance
Washer fluid tank ( P.324)
Engine coolant reservoir ( P.320)
Fuse boxes ( P.354)
Engine oil level dipstick ( P.319)
Engine oil filler cap ( P.319)
Power control unit coolant reservoir ( P.320)
Brake fluid reservoir ( P.322)
12-volt battery ( P.323)
Radiator ( P.321)
Condenser ( P.321)
Electric cooling fans
With the engine at operating temperature and turned off,
check the oil level on the dip-
stick.
Engine compar tment
Components
Checking and adding the
engine oil

3216-3. Do-it-yourself maintenance
6
Maintenance and care
Reservoir
“MAX” line
“MIN” line
If the level is on or below the “MIN”
line, add coolant up to the “MAX”
line. (P.414)
■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.
For the 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])
For 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 radiator, 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 condi-
tion, 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.
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.

3476-3. Do-it-yourself maintenance
6
Maintenance and care
ment may be required. (For sched-
uled maintenance information,
please refer to the “Scheduled
Maintenance Guide” or “Owner’s
Manual Supplement”.)
■If air flow from the vents
decreases dramatically
The filter may be clogged. Check
the filter and replace if necessary.
■Scheduled maintenance of the
air intake vent is necessary
when
In some situations such as when the
vehicle is used frequently or in
heavy traffic or dusty areas, the air
intake vent may need to be cleaned
more regularly. For d etails, refer to
“Scheduled Maintenance Guide” or
“Owner’s Manual Supplement”.
■Cleaning the air intake vent
Improper handling of the air intake
vent cover and filter may result in
damage to them. If you have any
concerns about cleaning the filter,
contact your Toyota dealer.
NOTICE
■When using the air condition-
ing system
Make sure that a filter is always
installed.
Using the air conditioning system
without a filter may cause damage
to the system.
■To prevent damage to the fil-
ter cover
When moving the filter cover in
the direction of arrow to release
the fitting, pay attention not to
apply excessive force to the
claws. Otherwise, the claws may
be damaged.
Cleaning the hybrid
batter y (traction bat-
ter y) air intake vents
To prevent the fuel economy
from being affected, visually
inspect the hybrid battery
(traction battery) air intake
vents periodically for clogs.
If it is dusty or clogged or if
“Maintenance Required for
Traction Battery Cooling
Parts See Owner’s Manual”
is displayed on the
multi-information display,
clean the air intake vent
using the following proce-
dures:

3486-3. Do-it-yourself maintenance
1Turn the power switch off.
2 Remove the air intake vent
cover.
Pull the cover as shown in
the illustration to disengage
the 7 claws, starting from the
claw in the upper right corner.
Pull the cover toward the
front of the vehicle to remove
it. 3
Remove the filter from the air
intake vent cover.
Disengage the claw as
shown in the illustration.
Remove the filter from the
cover.
If dust has accumulated on the
air intake vent cover, remove the
dust with a vacuum cleaner, etc.
4 Remove the dust and sand
from the filter.
Using a vacuum cleaner, etc.,
absorb dust and sand from the filter
by profiling the nozzle lightly along
the fold.
5Hold the filter to the light and
check if it is not clogged.
If the dust or sand cannot be
removed completely, contact your
NOTICE
■If “Maintenance Required for
Traction Battery Cooling
Parts See Owner’s Manual” is
displayed on the multi-infor-
mation display
Clean the air intake vent immedi-
ately.
If the vehicle is continuously
driven with the warning message
displayed, it may cause a mal-
function or output restriction of the
hybrid battery (tr action battery).
Cleaning procedure

3496-3. Do-it-yourself maintenance
6
Maintenance and care
Toyota dealer.
6Install the filter in its original
position, and then install the
air intake vent cover.
If “Maintenance Required for
Traction Battery Cooling Parts
See Owner’s Manual” is dis-
played on the multi-informa-
tion display
7 Start the hybrid system and
check that the warning mes-
sage is no longer displayed.
It may be necessary to drive the
vehicle for warning message is dis-
played again then disappears.
If the warning message does not
disappear after some time, have
the vehicle inspected by your Toy-
ota dealer.
■If the dust or sand on the filter
cannot be removed
It is recommended to use a vacuum
cleaner with plastic brushes.
WARNING
■When cleaning the air intake
vent
●Do not use water or other liq-
uids to clean the air intake vent.
If water is applied to the hybrid
battery (traction battery) or
other components, a malfunc-
tion or fire may occur.
●Before cleaning the air intake
vent, make sure to turn the
power switch off to stop the
hybrid system.
●Do not put a han d or leg in the
air intake vent. If it is caught in a
cooling fan, or if it touches a
high voltage part that results in
an electric shock, death or seri-
ous injuries may result.
NOTICE
■When cleaning the air intake
vent
Do not use an ai r blow gun, etc.
Dust may be blown out, possibly
causing a malfunction or output
restriction of the hybrid battery
(traction battery).
■To prevent damage to the
vehicle
Observe the following precau-
tions:
●Do not allow liquid or foreign
material to enter the air intake
vent.
●Make sure to reinstall the filter
and cover to their original posi-
tions after cleaning.
●Do not install anything to the air
intake vent other than the exclu-
sive filter for this vehicle or use
the vehicle witho ut the filter
installed.

3867-2. Steps to take in an emergency
ual Supplement” for the mainte-
nance interval applicable to your
vehicle.
■If “Maintenance Required Visit
Your Dealer” is displayed
Indicates that all maintenance is
required to correspond to the driven
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 maintenance. Please
reset the message after the mainte-
nance is performed. ( P.309)
*: Refer to the separate “Scheduled
Maintenance” or “Owner’s Man-
ual Supplement” for the mainte-
nance 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 a message that indicates the
need for visiting your Toyota
dealer is displayed
The system or part shown on the
multi-information display 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
displayed, follow the instructions
accordingly. ( P.414)
●If any of the following messages
are displayed on the multi-infor-
mation display, it may indicate a
malfunction. Have the vehicle
inspected by you r Toyota dealer immediately.
• “Smart Key System Malfunction”
• “Hybrid System Malfunction”
• “Check Engine”
• “Hybrid Battery System Malfunc- tion”
• “Accelerator System Malfunction”
●If any of the following messages
are displayed on the multi-infor-
mation display, it may indicate a
malfunction. Immediately stop the
vehicle and contact your Toyota
dealer.
• “Braking Power Low”
• “Charging System Malfunction”
• “Oil Pressure 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. ( P. 8 2 )
• “Hybrid System Stopped”
• “Engine Stopped”
●If “Maintenance Required for Trac-
tion Battery Cooling Parts See
Owner's Manual” is shown, the fil-
ters may be clogged, the air intake
vent may be blocked, or there may
be a gap in the duct. Therefore,
perform the follo wing correction
procedure.
• Cleaning the hybrid battery (trac-
tion battery) air intake vents.
( P.347)
If the warning message is shown
even if the vents are cleaned,
have the vehicle inspected by
your Toyota dealer.
NOTICE
■If “High Power Consumption
Power to Climate Temporar-
ily Limited” is displayed fre-
quently
There is a possible malfunction
relating to the charging system or
the 12-volt battery may be deteri-
orating. Have the vehicle
inspected by you r Toyota dealer.

4137-2. Steps to take in an emergency
7
When trouble arises
WARNING
■Avoiding 12-volt battery fires
or explosions
Observe the following precautions
to prevent accidentally igniting the
flammable gas that may be emit-
ted from the 12-volt battery:
●Make sure each jumper cable is
connected to the correct termi-
nal and that it is not unintention-
ally in contact with any other
than the intended terminal.
●Do not allow the other end of
the jumper cable connected to
the “+” terminal to come into
contact with any other parts or
metal surfaces in the area, such
as brackets or unpainted metal.
●Do not allow the + and - clamps
of the jumper cables to come
into contact with each other.
●Do not smoke, use matches,
cigarette lighters or allow open
flame near the 12-volt battery.
■12-volt battery precautions
The 12-volt battery contains poi-
sonous and corrosi ve acidic elec-
trolyte, while related parts contain
lead and lead compounds.
Observe the following precautions
when handling the 12-volt battery:
●When working with the 12-volt
battery, always wear safety
glasses and take care not to
allow any battery fluids (acid) to
come into contact with skin,
clothing or the vehicle body.
●Do not lean over the 12-volt bat-
tery.
●In the event that battery fluid
comes into contact with the skin
or eyes, immediately wash the
affected area with water and
seek medical attention. Place a
wet sponge or cloth over the
affected area until medical
attention can be received.
●Always wash your hands after
handling the 12-volt battery sup-
port, terminals, and other bat-
tery-related parts.
●Do not allow children near the
12-volt battery.
NOTICE
■When handling jumper cables
When connecting the jumper
cables, ensure that they do not
become entangled in the cooling
fans, etc.

4147-2. Steps to take in an emergency
If the engine coolant tempera-
ture gauge enters the red
zone or “Engine Coolant
Temp High Stop in a Safe
Place See Owner’s Manual”
is shown on the multi-informa-
tion 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 sub- sides.
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
5 Add coolant if necessary.
If your vehicle over-
heats
The following may indicate
that your vehicle is over-
heating.
The engine coolant tem-
perature gauge ( P. 9 9 ) i s
in the red zone or a loss of
hybrid system power is
experienced. (For example,
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