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395
3-1. Using the air conditioning system
and defogger
3
Interior features
SIENNA_OM_OM45472U_(U)Driver’s side temperature control dial
Turn the temperature control dial clockwise (warm) or coun-
terclockwise (cool).
If is not pressed, the system will blow ambient temperature air
or heated air.
For quick cooling, turn the temperature control dial to the “MAX A/C”
position. The air conditioning will automatically turn on and the air
circulation mode will be set to recirculated air mode.
When the dial is in the “MAX A/C” position, the air conditioning sys-
tem cannot be turned off even if is pressed.
Front passenger’s side temperature control dial
Turn the temperature control dial clockwise (warm) or counter
clockwise (cool).
STEP2
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665
4-3. Do-it-yourself maintenance
4
Maintenance and care
SIENNA_OM_OM45472U_(U)
CAUTION
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:
■
When working on the engine compartment:
● Keep hands, clothing and tools away from the moving fan and engine
drive belt.
● Be careful not to touch the engine, radiator, 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 compartment.
● Do not smoke, cause sparks or expose an open flame to fuel or the bat-
tery. Fuel and battery fumes are flammable.
● Be extremely cautious when working on the battery. It contains poisonous
and corrosive sulfuric acid.
■ When working near the electric c ooling fans or radiator grille
Vehicles without a smart key system: Be sure the engine switch is off. With
the engine switch in the “ON” position, the electric cooling fans may auto-
matically start to run if the air conditioning is on and/or the coolant tempera-
ture is high. ( P. 680)
Vehicles with a smart key system: Be sure the “ENGINE START STOP”
switch is off. With the “ENGINE START STOP” switch in IGNITION ON
mode, the electric cooling fans may automatically start to run if the air condi-
tioning is on and/or the coolant temperature is high. ( P. 680)
Page 671 of 876
671
4-3. Do-it-yourself maintenance
4
Maintenance and care
SIENNA_OM_OM45472U_(U)
Engine compar tment
1AR-FE engine
Washer fluid tank (P. 687)
Engine oil level dipstick ( P. 673)
Engine oil filler cap ( P. 675)
Engine coolant reservoir ( P. 678)Brake fluid reservoir
( P. 681)
Fuse box ( P. 712)
Battery ( P. 683)
Electric cooling fans
Condenser ( P. 680)
Radiator ( P. 680)
Page 672 of 876
672 4-3. Do-it-yourself maintenance
SIENNA_OM_OM45472U_(U)
2GR-FE engine
Washer fluid tank (P. 687)
Engine oil filler cap ( P. 675)
Engine oil level dipstick ( P. 673)
Engine coolant reservoir ( P. 678)Brake fluid reservoir
( P. 681)
Fuse box ( P. 712)
Battery ( P. 683)
Electric cooling fans
Condenser ( P. 680)
Radiator ( P. 680)
Page 678 of 876

678 4-3. Do-it-yourself maintenance
SIENNA_OM_OM45472U_(U)
Engine coolantThe coolant level is satisfactory if it is between the “FULL” and “LOW”
lines on the reservoir when the engine is cold.
Reservoir cap
“FULL”
“LOW”
If the level is on or below the
“LOW” line, add coolant up to the
“FULL” line.
■Coolant selection
Only use “Toyota Super Long Life Coolant” or 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 engine coolant, contact your Toyota dealer.
■ If the coolant level drops within a short time of replenishing
Visually check the radiator, hoses, engine 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 system.
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679
4-3. Do-it-yourself maintenance
4
Maintenance and care
SIENNA_OM_OM45472U_(U)
CAUTION
■
When the engine is hot
Do not remove the engine coolant reservoir cap.
The cooling system may be under pressure and may spray hot coolant if the
cap is removed, causing serious injuries, such as burns.
NOTICE
■When adding coolant
Coolant is neither plain water nor stra ight 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.
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680 4-3. Do-it-yourself maintenance
SIENNA_OM_OM45472U_(U)
Radiator and condenserCheck the radiator and condenser and clear away any foreign
objects.
If either of the above parts is extr emely dirty or you are not sure of
their condition, have your vehicle inspected by your Toyota dealer.
CAUTION
■When the engine is hot
Do not touch the radiator or condenser as they may be hot and cause seri-
ous injuries, such as burns.
■ When the electric cooling fan is operating
Do not touch the engine compartment.
Vehicles without a smart key system: With the engine switch in the “ON”
position, the electric cooling fans may automatically start to run if the air con-
ditioning is on and/or the coolant temperature is high. Be sure the engine
switch is in the “LOCK” position when working near the electric cooling fan or
radiator grille.
Vehicles with a smart key system: With the “ENGINE START STOP” switch
in IGNITION ON mode, the electric cooling fans may automatically start to
run if the air conditioning is on and/or the coolant temperature is high. Be
sure the “ENGINE START STOP” switch is OFF when working near the elec-
tric cooling fans or radiator grille.
Page 717 of 876
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4-3. Do-it-yourself maintenance
4
Maintenance and care
SIENNA_OM_OM45472U_(U)
FuseAmpereCircuit
24 FAN 60 A Electric cooling fans
25 HAZ 15 A Turn signal lights, gauges and
meters
26 RSE 15 A Rear seat entertainment system
27 MIRROR
*310 A Outside rear view mirror control,
outside rear view mirror heaters
28 AMP 30 A Audio system
29 VSC NO.2 30 A Vehicle dynamics integrated man-
agement, ABS, vehicle stability
control
30 ST 30 A Starting system
31 P/I 40 A Horn, left-hand headlight (low
beam), right-hand headlight (low
beam)
32 H-LP MAIN
*140 A Discharge headlight
SPARE
*430 A Spare-fuse
33 AM2
*530 A “ST NO.2”, “GAUGE NO.2” and
“IG2” fuses
34 VSC NO.1 50 A Vehicle dynamics integrated man-
agement, ABS, vehicle stability
control