engine coolant TOYOTA HIGHLANDER HYBRID 2023 User Guide

3926-3. Do-it-yourself maintenance
6-3.Do-it-yourself maintenance
Do-it-yourself ser vice
precautions
If you perform maintenance
by yourself, be sure to fol-
low the correct procedure
as given in these sections.
Maintenance
ItemsParts and tools
12-volt battery
condition
( P.402)
•Grease
• Conventional
wrench (for ter-
minal clamp
bolts)
Brake fluid
level ( P.400)
• FMVSS No.116
DOT 3 or SAE
J1703 brake fluid
• Rag or paper towel
• Funnel (used only for adding
brake fluid)
Engine/power
control unit
coolant level
( P.399)
• “Toyota Super
Long Life Cool-
ant” or a similar
high quality eth-
ylene gly-
col-based
non-silicate,
non-amine,
non-nitrite and
non-borate cool-
ant with long-life
hybrid organic
acid technology
For the U.S.A.:
“Toyota Super
Long Life Cool-
ant” is pre-mixed
with 50% cool-
ant and 50%
deionized water.
For Canada:
“Toyota Super
Long Life Cool-
ant” is pre-mixed
with 55% cool-
ant and 45%
deionized water.
• Funnel (used only for adding
coolant)
Engine oil level
( P.396)
• “Toyota Genuine
Motor Oil” or
equivalent
• Rag or paper towel
• Funnel (used only for adding
engine oil)
Fuses
( P.425)• Fuse with same
amperage rating
as original
ItemsParts and tools

3936-3. Do-it-yourself maintenance
6
Maintenance and care
Hybrid battery
(traction bat-
tery) air intake
vent (P.420)• Vacuum cleaner,
etc.
• Phillips screw- driver
Headlight aim
( P.427)• Phillips-head
screwdriver
Light bulbs
( P.428)
• Bulb with same
number and
wattage rating as
original
• Phillips-head screwdriver
• Flathead screw- driver
• Wrench
Radiator and
condenser
(  P.400)

Tire inflation
pressure
( P.415)• Tire pressure
gauge
• Compressed air source
Washer fluid
( P.401)
• Water or washer
fluid containing
antifreeze (for
winter use)
• Funnel (used only for adding
water or washer
fluid)
WARNING
The engine compartment contains
many mechanisms and fluids that
may move suddenly, become hot,
or become electrically energized.
To avoid death or serious injury,
observe the following precautions.
ItemsParts and tools■When working on the engine
compartment
●Make sure that the “ACCES-
SORY” or “IGNITION ON” on
the multi-information display
and the “READY” indicator are
both off.
●Be careful not to touch the
engine, power control unit, radi-
ator, exhaust manifold, etc. right
after driving as they may be hot.
Oil and other fluids may also be
hot.
●Do not leave anything that may
burn easily, such as paper and
rags, in the engine compart-
ment.
●Do not smoke, cause sparks or
expose an open flame to fuel.
Fuel fumes are flammable.
■When working near the elec-
tric cooling fan or radiator
grille
Be sure the power switch is off.
With the power switch in ON, the
electric cooling fa n may automati-
cally start to run if the air condi-
tioning is on and/or the coolant
temperature is high. ( P.400)
■Safety glasses
Wear safety glasses to prevent
flying or falling material, fluid
spray, etc. from getting in your
eyes.
NOTICE
■If you remove the air cleaner
filter
Driving with the air cleaner filter
removed may cause excessive
engine wear due to dirt in the air.

3966-3. Do-it-yourself maintenance
Engine coolant reservoir ( P.399)
Fuse boxes ( P.425)
Engine oil filler cap ( P.397)
Engine oil level dipstick ( P.397)
Brake fluid reservoir ( P.400)
Washer fluid tank ( P.401)
Electric cooling fan
Condenser ( P.400)
Radiator ( P.400)
Power control unit coolant reservoir ( P.399)
■12-volt battery
 P. 4 0 2
With the engine at operating
temperature and turned off,
check the oil level on the dip-
Engine compar tment
Components
Checking and adding the
engine oil

3996-3. Do-it-yourself maintenance
6
Maintenance and care■Engine coolant reservoir
The coolant level is satisfactory
if it is between the “FULL” and
“LOW” lines on the reservoir
when the engine is cold.
Reservoir cap
“FULL” line
“LOW” line
If the level is on or below the “LOW”
line, add coolant up to the “FULL”
line. ( P.484)
■Power control unit coolant
reservoir
The coolant level is satisfactory
if it is between the “FULL” and
“LOW” lines on the reservoir
when the hybrid system is cold.
Reservoir cap
“FULL” line
“LOW” line
If the level is on or below the “LOW”
line, add coolant up to the “FULL”
line. ( P.484)
■Coolant selection
Only use “Toyota Super Long Life
Coolant” or a similar high quality
ethylene glycol ba sed 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% c oolant and 50%
deionized water. (Minimum tem-
perature: -31°F [-35°C])
Canada:
“Toyota Super Long Life Coolant” is
a mixture of 55% c oolant and 45%
deionized water. (Minimum tem-
perature: -44°F [-42°C])
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 le vel 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

4006-3. Do-it-yourself maintenance
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.
■Checking fluid level
The brake fluid level should be
between the “MAX” and “MIN”
lines on the tank.
■Adding fluid
Make sure to check the fluid
type and prepare the necessary
item.
 Fluid type
SAE J1703 or FMVSS No.116 DOT
3 brake fluid
SAE J1704 or FMVSS No.116 DOT
4 brake fluid
Item
Clean funnel
WARNING
■When the hybrid system is
hot
Do not remove the engine/power
control unit coolant reservoir caps
and 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 d amaging 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.
Checking and adding the
brake fluid

4437-2. Steps to take in an emergency
7
When trouble arises
When using a flat-bed truck to
transport the vehicle, use tire
strapping belts. Refer to the
owner's manual of the flat-bed
truck for the tire strapping
method.
In order to suppress vehicle
movement during transporta-
tion, set the parking brake and
turn the power switch off. 
Fluid leaks under the vehicle
(Water dripping from the air
conditioning after use is nor-
mal.)
 Flat-looking tires or uneven
tire wear
 Engine coolant temperature
gauge needle continually
points higher than normal
 Changes in exhaust sound
 Excessive tire squeal when
cornering
 Strange noises related to the
suspension system
 Pinging or other noises
related to the hybrid system
 Engine missing, stumbling or
running roughly
 Appreciable loss of power
 Vehicle pulls heavily to one
NOTICE
■Towing with a sling-type truck
Do not tow with a sling-type truck
to prevent body damage.
2WD models
AWD models
Using a flatbed truck
NOTICE
■To prevent damage to the
vehicle during emergency
towing
Do not secure cables or chains to
the suspension components.
If you think something
is wrong
If you notice any of the fol-
lowing symptoms, your
vehicle probably needs
adjustment or repair. Con-
tact your Toyota dealer as
soon as possible.
Visible symptoms
Audible symptoms
Operational symptoms

4457-2. Steps to take in an emergency
7
When trouble arises
■Brake system warning light
■Brake system warning light
■High coolant temperature warning light* (warning buzzer)
*: This light illuminat es on the multi-information display.
If a war ning light tur ns on or a war ning buzzer
sounds
Calmly perform the following actions if any of the warning
lights comes on or flashes. If a light comes on or flashes, but
then goes off, this does not necessarily indicate a malfunction
in the system. However, if this continues to occur, have the
vehicle inspected by your Toyota dealer.
Actions to the warning lights or warning buzzers
Warning lightDetails/Actions
(U.S.A.)
or
(red)
(Canada)
Indicates that:
 The brake fluid level is low; or
 The brake system is malfunctioning
 Immediately stop the vehicle in a safe place and con-
tact your Toyota dealer. Continuing to drive the vehi-
cle may be dangerous.
Warning lightDetails/Actions
(yellow)
Indicates a malfunction in:
The regenerative braking system;
 The electronically contr olled brake system; or
 The electric parking brake
 Have the vehicle inspected by your Toyota dealer
immediately.
Warning lightDetails/Actions
Indicates that the engine coolant temperature is too high
Immediately stop the vehicle in a safe place.
Handling method ( P.484)

4607-2. Steps to take in an emergency
Check the engine oil and change it if
necessary. After changing the
engine oil, make sure to reset the
message. (P.398)
■If “Oil Maintenance Required” 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.398)
■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 any of the following messages
are shown on the multi-informa-
tion display, it may indicate a mal-
function. Immediat ely stop the
vehicle and contact your Toyota
dealer.
• “Braking Power Low Stop in a Safe Place See Owner's Manual”
• “Oil Pressure Low Stop in a Safe
Place See Owner's Manual”
• “Charging System Malfunction Stop in a Safe Place See Owner's
Manual”
• “Stop in a Safe Place See Owner's Manual”
• “Shift to P See Owner's Manual”
●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”
●If any of the following messages
are shown on the multi-informa-
tion display, it may indicate a mal- function. Have the vehicle
inspected by your Toyota dealer
immediately.
• “Hybrid System Malfunction”
• “Check Engine”
• “Hybrid Battery System Malfunc- tion”
• “Accelerator System Malfunction”
• “Smart Key System Malfunction See Owner's Manual”
●If any of the following messages
are shown on the multi-informa-
tion display, follow the instruc-
tions.
• “Engine Coolant Temp High Stop in a Safe Place See Owner's Man-
ual” ( P.484)
●If “Maintenance Required for Trac-
tion Battery Cooling Parts See
Owner's Manual” is shown, the fil-
ters may be clogged, the air intake
vents may be blocked, or there
may be a gap in the duct. There-
fore, perform the following correc-
tion procedure.
• Cleaning the hybrid battery (trac- tion battery) air intake vents
( P.420)
If the warning message is shown
even if the vents ar e cleaned, have
the vehicle inspected by your Toyota
dealer.
NOTICE
■If “High Power Consumption
Partial Limit on AC/Heater
Operation” 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.

4847-2. 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
NOTICE
■When handling jumper cables
When connecting the jumper
cables, ensure that they do not
become entangled in the cooling
fan or belt.
■To prevent damaging the
vehicle
The exclusive jump starting termi-
nal is to be used when charging
the 12-volt battery from another
vehicle in an emergency. It cannot
be used to jump start another
vehicle.
If your vehicle over-
heats
The following may indicate
that your vehicle is over-
heating.
 The needle of the engine
coolant temperature gauge
( P.87) enters 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-
p l a y.
 Steam comes out from
under the hood.
Correction procedures

4857-2. Steps to take in an emergency
7
When trouble arises
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 fan
If a large amount of coolant leaks,
immediately cont act your Toyota
dealer.
4 The coolant level is satisfac-
tory if it is between the
“FULL” and “LOW” lines on
the reservoir.
Reservoir
“FULL” line
“LOW” line Radiator cap
5 Add coolant if necessary.
Water can be used in an emer-
gency if coolant is unavailable.
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