2021 TOYOTA SIENNA HYBRID coolant temperature

982-1. Instrument cluster
Oil maintenance:
Displays the distance until the next engine oil change.
Shift position and shift range indicator
Displays the selected shift posit ion or selected shift range (P.238)
Outside temperature ( P.98)
Engine coolant temperature gauge
Displays the engine c oolant temperature
■The meters and display illumi-
nate when
The power swit ch is in ON.■When changing driving mode
Speedometer color is changed fol-
lowing the selected driving mode.
(  P.333)
■Hybrid System Indicator
READY OFF area
Shows that the hybrid system is not
operating.
Charge area
Shows regeneration
* status.
Regenerated e nergy will be used to
charge the hybrid battery (traction
battery).
Hybrid Eco area
Shows that gasoline engine power
is not being used very often.
The gasoline engine will automati- cally stop and restart under various
conditions.
Eco area
Shows that the vehicle is being
driven in an Eco-friendly manner.
By keeping the indicator needle
within Eco area, more Eco-friendly
driving can be achieved.
Power area
Shows that an Eco-friendly driving
range is being exceeded (during full
power driving etc.)
*: When used in this manual, “regen-
G
H
I
A
B
C
D
E

992-1. Instrument cluster
2
Vehicle status information and indicators
eration” refers to the conversion of
energy created by the movement
of the vehicle into electrical
energy.
In the following situ ation, the Hybrid
System Indicator does not operate.
●“READY” indicator is not illumi-
nated.
●The shift lever is in a range other
than D or S.
■Outside temperature display
●In the following si tuations, the cor-
rect outside tempe rature may not
be displayed, or the display may
take longer than normal to
change.
• When stopped, or driving at low speeds (less than 12 mph [20
km/h])
• When the outside temperature has changed suddenly (at the
entrance/exit of a garage, tunnel,
etc.)
●When “--” or “E” is displayed, the
system may be malfunctioning.
Take your vehicle to your Toyota
dealer.
●Displays the outside temperature
within the range of -40°F (-40°C)
to 122°F (50°C).
●When the outside temperature is
approximately 37°F (3°C) or
lower, the low outside temperature
indicator will flash for approxi-
mately 10 seconds , then stay on.
■Liquid crystal display
 P.105Switches the items of the odom-
eter, trip meter A, trip meter B
and oil maintenance by pressing
the “ODO TRIP” switch.
When the trip meter is dis-
played, pressing and holding the
switch will reset the trip meter.
WARNING
■The information display at
low temperatures
Allow the interior of the vehicle to
warm up before using the liquid
crystal information display. At
extremely low temperatures, the
display monitor may respond
slowly, and display changes may
be delayed.
For example, there is a lag
between the driver’s shifting and
the new shift range appearing on
the display. This lag could cause
the driver to downshift again,
causing rapid and excessive
engine braking and possibly an
accident resulting in death or
injury.
NOTICE
■To prevent damage to the
engine and its components
The engine may be overheating if
the engine coolant temperature
gauge is in the red zone (“H”). In
this case, immediately stop the
vehicle in a safe place, and check
the engine after it has cooled
completely. ( P.511)
Changing the trip meter
display

1022-1. Instrument cluster
Oil maintenance:
Displays the distance until the next engine oil change.
Shift position and shift range indicator
Displays the selected shift posit ion or selected shift range (P.238)
Outside temperature ( P.102)
Engine coolant temperature gauge
Displays the engine c oolant temperature
■The meters and display illumi-
nate when
The power swit ch is in ON.■When changing driving mode
Speedometer color is changed fol-
lowing the selected driving mode.
(  P.333)
■Hybrid System Indicator
READY OFF area
Shows that the hybrid system is not
operating.
Charge area
Shows regeneration
* status. Regen-
erated energy will be used to charge
the hybrid battery (traction battery).
Hybrid Eco area
Shows that gasoline engine power
is not being used very often.
The gasoline engine will automati-
cally stop and rest art under various
conditions. Eco area
Shows that the vehicle is being
driven in an Eco-friendly manner.
By keeping the indicator needle
within Eco area, more Eco-friendly
driving can be achieved.
Power area
Shows that an Eco-friendly driving
range is being exceeded (during full
power driving etc.)
*: When used in this manual, “regen- eration” refers to the conversion of
energy created by the movement
of the vehicle into electrical
G
H
I
A
B
C
D
E

1032-1. Instrument cluster
2
Vehicle status information and indicators
energy.
In the following situ ation, the Hybrid
System Indicator does not operate.
●“READY” indicator is not illumi-
nated.
●The shift lever is in a range other
than D or S.
■Outside temperature display
●In the following si tuations, the cor-
rect outside tempe rature may not
be displayed, or the display may
take longer than normal to
change.
• When stopped, or driving at low speeds (less than 12 mph [20
km/h])
• When the outside temperature has changed suddenly (at the
entrance/exit of a garage, tunnel,
etc.)
●When “--” or “E” is displayed, the
system may be malfunctioning.
Take your vehicle to your Toyota
dealer.
●Displays the outside temperature
within the range of -40°F (-40°C)
to 122°F (50°C).
●When the outside temperature is
approximately 37°F (3°C) or
lower, the low outside temperature
indicator will flash for approxi-
mately 10 seconds , then stay on.
■Liquid crystal display
 P.105
■Customization
Settings (e. g. meter display) can be
changed on the screen of the
multi-informat ion display. (P.541)Switches the items of the odom-
eter, trip meter A, trip meter B
and oil maintenance by pressing
the “ODO TRIP” switch.
When the trip meter is dis-
played, pressing and holding the
switch will reset the trip meter.
WARNING
■The information display at
low temperatures
Allow the interior of the vehicle to
warm up before using the liquid
crystal information display. At
extremely low temperatures, the
display monitor may respond
slowly, and display changes may
be delayed.
For example, there is a lag
between the driver’s shifting and
the new shift range appearing on
the display. This lag could cause
the driver to downshift again,
causing rapid and excessive
engine braking and possibly an
accident resulting in death or
injury.
NOTICE
■To prevent damage to the
engine and its components
The engine may be overheating if
the engine coolant temperature
gauge is in the red zone (“H”). In
this case, immediately stop the
vehicle in a safe place, and check
the engine after it has cooled
completely. ( P.511)
Changing the trip meter
display

2284-1. Before driving
Avoid jerky starts or sudden
acceleration.
 Avoid jerky steering and
sharp turns, and slow down
before making turn.
 Note that when making a turn,
the trailer wheels will be
closer than the vehicle wheels
to the inside of the turn. Com-
pensate by making a wider
than normal turning radius.
 Slow down before making a
turn, in cross winds, on wet or
slippery surfaces, etc.
Increasing vehicle speed can
destabilize the trailer.
Take care when passing other
vehicles. Passing requires
considerable distance. After
passing a vehicle, do not for-
get the length of your trailer,
and be sure you have plenty
of room before changing
lanes.
 To maintain engine braking
efficiency and charging sys-
tem performance, when using
engine braking, do not use
the transmission in D.
 Instability happens more fre-
quently when descending
steep or long downhill grades.
Before descending, slow
down and downshift. Do not
make sudden downshifts
while descending steep or
long downhill grades.
 Avoid holding the brake pedal down too long or applying the
brakes too frequently. This
could cause the brakes to
overheat and result in
reduced braking efficiency.
 Due to the added load of the
trailer, your vehicle’s hybrid
system may overheat on hot
days (at temperatures over
85°F [30°C]) when driving up
a long or steep grade. If the
engine coolant temperature
gauge indicates overheating,
immediately turn off the air
conditioning (if in use), pull
your vehicle off the road and
stop in a safe spot. ( P.511)
 Always place wheel blocks
under both the vehicle’s and
the trailer’s wheels when
parking. Apply the parking
brake firmly, and put the
transmission in P. Avoid park-
ing on a slope, but if unavoid-
able, do so only after
performing the following:
1 Apply the brakes and keep
them applied.
2 Have someone place wheel
blocks under both the vehi-
cle’s and trailer’s wheels.
3 When the wheel blocks are in
place, release the brakes
slowly until the blocks absorb
the load.
4 Apply the parking brake
firmly.

4126-3. Do-it-yourself maintenance
Hybrid bat-
tery (traction
battery) air
intake vent
( P.443)• Vacuum cleaner,
etc,
• Phillips screw- driver
Light bulbs
( P.451)
• Bulb with same
number and watt-
age rating as origi-
nal
• Phillips-head screwdriver
• Flathead screw- driver
• Wrench
Radiator and
condenser
(  P.420)

Tire inflation
pressure
( P.438)• Tire pressure
gauge
• Compressed air source
Washer fluid
( P.421)
• Water or washer
fluid containing
antifreeze (for win-
ter 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 “IGNITION ON”
on the multi-information display
and the “READY” indicator are
both off.
●Keep hands, clothing and tools
away from the moving fan.
●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 or
the battery. Fuel and battery
fumes are flammable.
●Be extremely cautious when
working on the battery. It con-
tains poisonous and corrosive
sulfuric acid.
■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.420)
■Safety glasses
Wear safety gla sses to prevent
flying or falling material, fluid
spray, etc., from getting in your
eyes.

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
I
J
&KHFNLQJDQGDGGLQJWKH
HQJLQHRLO

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