2023 TOYOTA SEQUOIA HYBRID cooling

4656-3. Do-it-yourself maintenance
Owners Manual_USA_M0C043_en
6
Maintenance and care
Fuse boxes ( P.495)
Power control unit coolant reservoir ( P.468)
Intercooler coolant reservoir ( P.468)
Engine coolant reservoir ( P.468)
Engine oil filler cap ( P.466)
Engine oil level dipstick ( P.466)
Brake fluid reservoir ( P.469)
Engine radiator ( P.469)
Condenser ( P.469)
Electric cooling fans
Radiator cooling fan ( P.468)
Washer fluid tank ( P.470)
Intercooler radiators ( P.468)
Engine compar tment
Components

4696-3. Do-it-yourself maintenance
Owners Manual_USA_M0C043_en
6
Maintenance and care
“LOW” line
If the level is on or below the “LOW”
line, add coolant up to the “FULL”
line. ( P.543)
■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 temperature: -31°F [-
35°C])
Canada: “Toyota Super Long Life
Coolant” is a mixture of 55% coolant
and 45% deionized water.
(Minimum temperature: -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 coolant reser voir cap, inter-
coolant reservoir cap, 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, condenser
and intercooler radiators and
clear away any foreign 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.
■Checking fluid level
The brake fluid level should be
between the “MAX” and “MIN”
WARNING
■When the hybrid system is
hot
Do not remove the coolant reser-
voir 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,
condenser and inter-
cooler radiators
WARNING
■When the hybrid system is
hot
Do not touch the radiator, con-
denser or intercooler radiators or
condenser as they may be hot
and cause serious injuries, such
as burns.
Checking and adding the
brake fluid

4896-3. Do-it-yourself maintenance
Owners Manual_USA_M0C043_en
6
Maintenance and care
Remove the dust from the air
intake vents with a vacuum
cleaner, etc.
Make sure to only use a vacuum to
suck out dust and clogs. Attempting
to blow out dust and clogs using an
airgun, etc. may push it into the air
intake vents. ( P.492)
If dust and clogs cannot be com-
pletely removed with the air
intake vent cover installed,
remove the cover and clean the
filter.
1Turn the power switch off.
2 Using a flathead screwdriver,
remove the air intake vent
cover.
3 Vehicles with third seat
(power type): Remove the
Cleaning the hybrid
batter y (traction bat-
ter y) air intake vent
and filter
To prevent the fuel economy
from being affected, visually
inspect the hybrid battery
(traction battery) air intake
vent periodically for dust
and clogs. If it is dusty or
clogged or if “Maintenance
Required for Traction Bat-
tery Cooling Parts See
Owner’s Manual” is dis-
played on the multi-informa-
tion display, clean the air
intake vent using the follow-
ing procedures:
Cleaning the air intake
vents
If dust and clogs cannot
be completely removed

4916-3. Do-it-yourself maintenance
Owners Manual_USA_M0C043_en
6
Maintenance and care
8 Install the air intake vent
cover.
1 Insert the cover to engage
the 2 claws.
2 Install the cover as shown in
the illustration.
■Scheduled maintenance of the
air intake vents is necessary
when
In some situations such as when the
vehicle is used frequently or in
heavy traffic or dusty areas, the air
intake vents may need to be
cleaned more regularly. For details,
refer to the “Owner’ s Warranty Infor-
mation Booklet” or “Owner’s Manual
Supplement”.
■Cleaning the air intake vent
●Dust in the air intake vent may
interfere with the cooling of the
hybrid battery (traction battery). If
charging/discharging of the hybrid
battery (traction battery) becomes
limited, the distance that the vehi-
cle can be driven using the electric
motor (traction motor) may be
reduced and the fuel economy
may be reduced.
Inspect and clean the air intake
vent periodically.
●Improper handling of the air intake
vent cover and filt er may result in
damage to them. If you have any
concerns about cleaning the filter,
contact your Toyota dealer.
■If “Maintenance Required for
Traction Battery Cooling Parts
See Owner’s Manual” is dis-
played on the multi-information
display
●If this warning message is dis-
played on the multi-information
display, remove the air intake vent
cover and clean the filter.
(  P.489)
●After cleaning the air intake vent,
start the hybrid system and check
that the warning message is no
longer shown.
It may take approximately 20 min-
utes after the hybrid system is
started until the warning message
disappears. If the warning mes-
sage does not disappear, have the
vehicle inspected by your Toyota
dealer.
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.

4926-3. Do-it-yourself maintenance
Owners Manual_USA_M0C043_en
NOTICE
■When cleaning the air intake
vent
When cleaning the air intake vent,
make sure to only use a vacuum
to suck out dust and clogs. If a
compressed air blow gun, etc. is
used to blow out dust and clogs,
the dust or clogs may be pushed
into the air intake vent, which may
affect the performance of the
hybrid battery (tr action battery)
and cause a malfunction.
■To prevent damage to the
vehicle
●Do not allow water or foreign
matter to enter t he air intake
vent when the cover is
removed.
●Carefully handle the removed
filter so that it will not be dam-
aged.
If the filter is damaged, have it
replaced with a new filter by
your Toyota dealer.
●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.
■If “Maintenance Required for
Traction Battery Cooling
Parts See Owner’s Manual” is
displayed on the multi-infor-
mation display
If the vehicle is continuously
driven with the warning message
(indicating that charging/discharg-
ing of the hybrid battery [traction
battery] may become limited) dis-
played, the hybrid battery (traction
battery) may malfunction. If the
warning message is displayed,
clean the air intake vent immedi-
ately.

5207-2. Steps to take in an emergency
Owners Manual_USA_M0C043_entems such as PCS (Pre-Collision
system) or the dynamic radar cruise
control with full-speed range is oper-
ating. If a warning message is
shown, be sure to decelerate the
vehicle or follow an instruction
shown on the multi
-information dis-
play.
A warning message is shown when
Brake Override System operates.
(  P.188)
A warning message is shown when
Drive-Start Control ( P.193) or
Parking Support Brake (if equipped)
(  P.307) operates. Follow the
instructions on the multi-information
display.
●If a message about an operation
of the power switch is displayed
An instruction for operation of the
power switch is shown when the
incorrect procedure for starting the
hybrid system is performed or the
power switch is operated incorrectly.
Follow the instructions shown on the
multi-information display to operate
the power switch again.
●If a message abou t a shift lever
operation is displayed
To prevent the shift lever from being
operated incorrectly or the vehicle
from moving unexpectedly, a mes-
sage that requires shifting the shift
lever may be sho wn on the multi-
information display . In that case, fol-
low the instruction of the message
and shift the shift lever.
●If a message or image about an
open/close state of a part or
replenishment of a consumable is
displayed
Confirm the part indicated by the
multi-information display 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
Stop in a Safe Place See Owner’s
Manual” is shown, follow the
instructions ( P.543).
●If the following messages are
shown, there may be a malfunc-
tion.
Immediately stop the vehicle in a
safe place and contact your Toy-
ota dealer. Continuing to drive the
vehicle may be dangerous.
• “Hybrid System Malfunction”
• “Check Engine”
• “Traction battery system malfunc- tion”
• “Accelerator System Malfunction”
• “Hybrid System Stopped”
• “Smart Key System Malfunction See Owner’s Manual”
●If the following messages are
shown, there may be a malfunc-
tion.
Immediately have the vehicle
inspected by your Toyota dealer.
• “Oil Pressure Low Stop in a Safe Place See Owner’s Manual”
• “Braking Power Low Stop in a
Safe Place See Owner’s Manual”
●If “Maintenance Required for Trac-
tion Battery Cooling Parts See
Owner’s Manual” is shown, the fil-
ter 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.
• If the air intake vent or filter of the

5427-2. Steps to take in an emergency
Owners Manual_USA_M0C043_en
WARNING
●When working with the 12-volt
battery, always wear safety
glasses and take care not to
allow any 12-volt 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 12-volt 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.
■After recharging the 12-volt
battery
Have the 12-volt battery
inspected at your Toyota dealer
as soon as possible. If the 12-volt
battery is deteriorating, continued
use may cause the 12-volt battery
to emit a malodorous gas, which
may be detrimental to the health
of passengers.
■When replacing the 12-volt
battery
●For information regarding 12-
volt battery replacement, con-
tact your Toyota dealer.
●After replacing, s ecurely attach
the exhaust hose and exhaust
hole plug to the exhaust hole of
the replaced 12-volt battery. If
not properly installed, gases
(hydrogen) may leak into the
vehicle interior, and there is the
possible danger of the gas ignit-
ing and exploding.
NOTICE
■When handling jumper cables
When connecting the jumper
cables, ensure that they do not
become entangled in the cooling
fan.

5437-2. Steps to take in an emergency
Owners Manual_USA_M0C043_en
7
When trouble arises
■If the engine coolant tem-
perature gauge enters the
red zone 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, engine
radiator core (radiator) and
intercooler radiator core
(radiator) for any leaks.
If a large amount of coolant leaks,
immediately cont act your Toyota dealer.
Cooling fan
Radiator
Intercooler radiators
4 The coolant level is satisfac-
tory if it is between the “F” or
“FULL” and “L” or “LOW”
lines on the reservoir.
If your vehicle overheats
The following may indicate that your vehicle is overheating.
The needle of the engine coolant temperature gauge ( P.93)
enters the red zone or a loss of engine (hybrid system) power i s
experienced. (For example, the vehicle speed does not
increase.)
 “Engine Coolant Temp High Stop in a Safe Place See Owner’s
Manual” is shown on the multi-information display.
Steam comes out from under the hood.
Correction procedures