2021 TOYOTA HIGHLANDER HYBRID check engine

4106-2. Maintenance
HIGHLANDER HV_U
The OBD system determines
that a problem exists some-
where in the emission control
system. Your vehicle may not
pass the I/M test and may need
to be repaired. Contact your
Toyota dealer to service the
vehicle.
When the 12-volt battery is
disconnected or discharged
Readiness codes that are set
during ordinary driving are erased.
Also, depending on your driving
habits, the readiness codes may
not be completely set.
When the fuel tank cap is
loose
Vehicle exterior
ItemsCheck points
Doors
• Do the doors
operate
smoothly?
Engine hood
• Does the engine hood lock system
work properly?
Fluid leaks
• There should not be any signs of
fluid leakage
after the vehicle
has been parked.
Tires
• Is the tire infla-tion pressure
correct?
• The tires should not be damaged
or excessively
worn.
• Have the tires been rotated
according to the
maintenance
schedule?
• The wheel nuts should not be
loose.
Windshield
wipers/rear
window wiper
• The wiper blades should not show
any signs of
cracking, split-
ting, wear, con-
tamination or
deformation.
• The wiper blades should clear the
windshield/rear
window without
streaking or skip-
ping.
Emission inspection
and maintenance (I/M)
programs
Some states have vehicle
emission inspection pro-
grams which include OBD
(On Board Diagnostics)
checks. The OBD system
monitors the operation of
the emission control sys-
tem.
If the malfunction indica-
tor lamp comes on
Your vehicle may not pass
the I/M test in the follow-
ing situations:

4166-3. Do-it-yourself maintenance
HIGHLANDER HV_U
Engine coolant reservoir ( P.418)
Fuse boxes ( P.446)
Engine oil filler cap ( P.417)
Engine oil level dipstick ( P.417)
Brake fluid reservoir ( P.420)
Washer fluid tank ( P.420)
Electric cooling fan
Condenser ( P.419)
Radiator ( P.419)
Power control unit coolant reservoir ( P.419)
■12-volt battery
 P. 4 2 1
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

4176-3. Do-it-yourself maintenance
6
Maintenance and care
HIGHLANDER HV_U
stick.
■Checking the engine oil
1 Park the vehicle on level
ground. After warming up the
engine and turning off the
hybrid system, wait more
than 5 minutes for the oil to
drain back into the bottom of
the engine.
2 Holding a rag under the end,
pull the dipstick out.
3 Wipe the dipstick clean.
4 Reinsert the dipstick fully.
5 Holding a rag under the end,
pull the dipstick out and
check the oil level.
Low
Normal
Excessive
The shape of the dipstick may differ depending on the type of vehicle or
engine.
6
Wipe the dipstick and reinsert
it fully.
■Checking the oil type and
preparing the item needed
Make sure to check the oil type
and prepare the items needed
before adding oil.
 Engine oil selection
P.512
 Oil quantity (Low  Full)
1.6 qt. (1.5 L, 1.3 Imp. qt.)
 Item
Clean funnel
■Adding engine oil
If the oil level is below or near
the low level mark, add engine
oil of the same type as that
already in the engine.
1 Remove the oil filler cap by
turning it counterclockwise.
2 Add engine oil slowly, check-
ing the dipstick.
3 Install the oil filler cap by
turning it clockwise.
■Engine oil consumption
A certain amount of engine oil will

4186-3. Do-it-yourself maintenance
HIGHLANDER HV_Ube consumed while driving. In the
following situatio
ns, oil consump-
tion may increase, and engine oil
may need to be ref illed in between
oil maintenance intervals.
●When the engine is new, for
example directly after purchasing
the vehicle or after replacing the
engine
●If low quality oil or oil of an inap-
propriate viscosity is used
●When driving at high engine
speeds or with a heavy load,
when towing, or when driving
while accelerating o r decelerating
frequently
●When leaving the engine idling for
a long time, or wh en driving fre-
quently through heavy traffic
■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.
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 an d 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 rea ch of children.
NOTICE
■To prevent serious engine
damage
Check the oil le vel on a regular
basis.
■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

4196-3. Do-it-yourself maintenance
6
Maintenance and care
HIGHLANDER HV_U
Reservoir cap
“FULL” line
“LOW” line
If the level is on or below the “LOW”
line, add coolant up to the “FULL”
line. (P.504)
■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.504)
■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% c
oolant 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-
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 damaging parts or
paint.
Checking the radiator and
condenser

4466-3. Do-it-yourself maintenance
HIGHLANDER HV_U
1Turn the power switch off.
2 Open the fuse box cover.
Engine compartment: type A
fuse box (if equipped)
Push the tab in and lift the lid off.
Engine compartment: type B
fuse box
Push the tab in and lift the lid off.
Under the driver’s side instru-
ment panel
Remove the lid.
Make sure to push the claw when
removing/installing the lid.
Right side luggage compart-
ment
Folding down the third seats.
(  P.158)
Disengage the claw and open the
cover.
3 Remove the fuse.
Only type A fuse can be removed
using the pullout tool.
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

4777-2. Steps to take in an emergency
7
When trouble arises
HIGHLANDER HV_U
The warning lights and warning buzzers operate as follows depend-
ing on the content of the message. If a message indicates the need
for inspection by a dealer, have the vehicle inspected by your To y o t a
dealer immediately.
*: A buzzer sounds the first time a message is shown on the multi-informa-
tion display.
■Warning messages
The warning messages explained
below may differ from the actual
messages according to operation
conditions and vehicle specifica-
tions.
■Warning buzzer
In some cases, the buzzer may not
be heard due to being in a noisy
location or audio sound.
■If “Engine Oil Level Low Add or
Replace” is displayed
The engine oil level is low. Check
the level of the engine oil, and add if
necessary.
This message may appear if the
vehicle is stopped on a slope. Move
the vehicle to a l evel surface and
check to see if the message disap-
pears.
Messages and warnings
Warning lightWarning
buzzer
*Warning
-Sounds
 Indicates an important situation, such as
when a system relate d to driving is mal-
functioning or that danger may result if
the correction procedure is not per-
formed
 Indicates a situation, such as when dam-
age to the vehicle or danger may result
Comes on or
flashesSounds
Indicates an importan t situation, such as
when the systems shown on the
multi-information display may be malfunc-
tioning
-Does not sound
 Indicates a condition, such as malfunc-
tion of electrical components, their condi-
tion, or indicates the need for
maintenance
 Indicates a situatio n, such as when an
operation has been performed incor-
rectly, or indicates how to perform an
operation correctly

4807-2. Steps to take in an emergency
HIGHLANDER HV_Uare 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 you r 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.504)
• “Maintenance Required for Trac- tion Battery Cooling Parts See
Owner's Manual” ( P.441)
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.