engine TOYOTA SIENNA HYBRID 2021 (in English) Workshop Manual

4136-3. Do-it-yourself maintenance
6
Maintenance and care
1Pull the hood lock release
lever.
The hood will pop up slightly.
2Push the auxiliary catch lever
to the left and lift the hood.
NOTICE
■If you remove th e air cleaner
filter
Driving with the air cleaner filter
removed may cause excessive
engine wear due to dirt in the air.
Hood
Release the lock from the
inside of the vehicle to open
the hood.
Opening the hood

4166-3. Do-it-yourself maintenance
Fuse box (P.449)
Engine oil filler cap ( P.417)
Engine oil level dipstick ( P.416)
Brake fluid reservoir ( P.420)
Radiator ( P.420)
Electric cooling fan
Condenser ( P.420)
Power control unit coolant reservoir ( P.419)
Washer fluid tank ( P.421)
Engine coolant reservoir ( P.419)
■12-volt battery
 P.422
With the engine at operating
temperature and turned off,
Engine compartment
Components
A
B
C
D
E
F
G
H
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4176-3. Do-it-yourself maintenance
6
Maintenance and care
check the oil level on the dip-
stick.
■Checking the engine oil
1 Park the vehicle on level
ground. After warming up the
engine and turning off the
engine, 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.
6Wipe the dipstick and reinsert
it fully.
■Checking the oil type and
preparing the items needed
Make sure to check the oil type
and prepare the items needed
before adding oil.
 Engine oil selection
P.521
 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.
A
B
C

4186-3. Do-it-yourself maintenance
■Engine oil consumption
A certain amount of engine oil will
be 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
■After changing the engine oil
The engine oil maintenance data
should be reset. Perform the follow-
ing procedures:
4.2-inch display
1 Press or of the meter
control switches to select on
the multi-information display.
2 Press or of the meter
control switches, select “Vehicle
Settings” and then press and
hold “OK”.
7-inch display
1 Press or of the meter
control switches to select on
the multi-information display.
2 Press or of the meter
control switches, select and
then press and hold “OK”.
3 Press or of the meter
control switch es, select “Oil Maintenance” and then press
“OK”.
4 Select “Yes” and press “OK”.
A message will be displayed on the
multi-informat ion display.
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 h ousehold 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
■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.

4196-3. Do-it-yourself maintenance
6
Maintenance and care
The coolant level is satisfactory
if it is between the “FULL” and
“LOW” lines on the reservoir
when the hybrid system is cold.
■Engine coolant reservoirReservoir cap
“FULL” line
“LOW” line
If the level is on or below the “LOW”
line, add coolant up to the “FULL”
line. ( P.511)
■Power control unit coolant
reservoir
Reservoir cap
“FULL” line
“LOW” line
If the level is on or below the “LOW”
line, add coolant up to the “FULL”
line. ( P.512)
■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])
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
NOTICE
●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

4206-3. Do-it-yourself maintenance
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.
■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
FMVSS No.116 DOT 3 or SAE
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
B e s ur e t o wa sh it o ff w ith w at er 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.
■When the electric cooling fan
is operating
Do not touch the engine compart-
ment.
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. Be sure the
power switch is OFF when work-
ing near the electric cooling fan or
radiator grille.
Checking and adding the
brake fluid

4216-3. Do-it-yourself maintenance
6
Maintenance and care
J1703 brake fluid
FMVSS No.116 DOT 4 or SAE
J1704 brake fluid
Item
Clean funnel
■Brake fluid can absorb moisture
from the air
Excess moisture in the brake fluid
can cause a dangerous loss of brak-
ing efficiency. Use only newly
opened brake fluid.
If any washer does not work or
“Windshield Washer Fluid Low”
is shown on the multi-informa-
tion display, the washer tank
may be empty. Add washer
fluid.
WARNING
■When filling the reservoir
Take care as brake fluid can harm
your hands and eyes and damage
painted surfaces.
If fluid gets on your hands or in
your eyes, flush th e affected area
with clean water immediately.
If you still experien ce discomfort,
see a doctor.
NOTICE
■If the fluid level is low or high
It is normal for the brake fluid level
to go down slightly as the brake
pads wear out or when the fluid
level in the accumulator is high.
If the reservoir needs frequent
refilling, there may be a serious
problem.
Adding the washer fluid
WARNING
■When adding washer fluid
Do not add washer fluid when the
hybrid system is hot or operating
as washer fluid contains alcohol
and may catch fire if spilled on the
hybrid system, etc.
NOTICE
■Do not use any fluid other
than washer fluid
Do not use soapy water or engine
antifreeze instead of washer fluid.
Doing so may cause streaking on
the vehicle’s painted surfaces, as
well as damaging the pump lead-
ing to problems of the washer
fluid not spraying.
■Diluting washer fluid
Dilute washer fluid with water as
necessary.
Refer to the freezing tempera-
tures listed on the label of the
washer fluid bottle.

4496-3. Do-it-yourself maintenance
6
Maintenance and care
1Turn the power switch off.
2 Open 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
Remove the cover
3Remove the fuse.
Only type A fuse c an be removed
using the pullout tool.
4 Check if the fuse is blown.
Replace the blown fuse with a new
fuse of an appropriate amperage
rating. The amperage rating can be
found on the fuse box lid.
Type A
Normal fuse
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
ABC
A

4506-3. Do-it-yourself maintenance
Blown fuse
Type B
Normal fuse
Blown fuse
Type CNormal fuse
Blown fuse
■After a fuse is replaced
●When installing the lid, make sure
that the tab is installed securely.
●If the lights do n ot turn on even
after the fuse has been replaced,
a bulb may need replacement.
(  P.451)
●If the replaced fuse blows again,
have the vehicle inspected by
your Toyota dealer.
■If there is an overload in a cir-
cuit
The fuses are designed to blow,
protecting the wiring harness from damage.
■When replacing light bulbs
Toyota recommends that you use
genuine Toyota products designed
for this vehicle. Because certain
bulbs are connected to circuits
designed to prevent overload, non-
genuine parts or parts not designed
for this vehicle may be unusable.
B
A
B
A
B
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.

4657-2. Steps to take in an emergency
7
When trouble arises
Fluid leaks under the vehicle
(Water dripping from the air
conditioning after use or drip-
ping from the muffler 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
side when braking
 Vehicle pulls heavily to one
side when driving on a level
road
 Loss of brake effectiveness,
spongy feeling, pedal almost
touches the floor
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