2004 TOYOTA SIENNA cooling

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2004 SIENNA from Aug. ’04 Prod. (OM45422U)
Idling for a long period with the air
conditioning on in stop−and− go traffic.
Towing a trailer.
It is not a malfunction even if the needle
of the engine coolant temperature gauge
returns to “C” when the ignition switch is
turned to the “START” position.
NOTICE
 Do not remove the thermostat in
the engine cooling system as this
may cause the engine to overheat.
The thermostat is designed to con-
trol the flow of coolant to keep the
temperature of the engine within
the specified operating range.
 Do not continue driving with an
overheated engine. See “If your ve-
hicle overheats” on page 410 in
Section 4.
The tachometer indicates engine speed
in thousands of rpm (revolutions per
minute). Use it while driving to select
correct shift points and to prevent en-
gine lugging and overrevving.
Driving with the engine running too fast
causes excessive engine wear and poor
fuel economy. Remember, in most cases
the slower the engine speed, the greater
the fuel economy.
It is not a malfunction even if the needle
of the tachometer returns to the bottom
position when the ignition switch is turned
to the “START” position.
NOTICE
Do not let the indicator needle get
into the red zone. This may cause
severe engine damage.
Tachometer

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Fan speed selector
Turn the knob to adjust the fan speed—to
the right to increase, to the left to de-
crease.
Temperature selector
Turn the knob to adjust the temperature—
to the right to warm, to the left to cool.
Air flow selector
Turn the knob to select the vents used for
air flow.1. Panel— Air flows from the instrument
panel vents.
2. Bilevel— Air flows from both the floor
vents and the instrument panel vents.
3. Floor— Air flows mainly from the floor
vents.
4. Floor/Windshield— Air flows mainly
from the floor vents and windshield
vents.
Turning the air flow selector to the
floor/windshield position turns on the
defogging function with the purpose of
clearing the front view. This position allows the air intake to
select FRESH automatically. This is to
clean up the front view more quickly.
If you want to return the setting to
RECIRCULATE mode, press the air in-
take selector button once again.
Press the “A/C” button for dehumidified
heating or cooling. This setting clears
the front view more quickly.
5. Windshield— Air flows mainly from the
windshield vents.
Turning the air flow selector to the
windshield position turns on the defog-
ging function with the purpose of clear-
ing the front view.
This position allows the air intake to
select FRESH automatically. This is to
clean up the front view more quickly.
If you want to return the setting to
RECIRCULATE mode, press the air in-
take selector button once again.
Press the “A/C” button for dehumidified
heating or cooling. This setting clears
the front view more quickly.
For details about air flow selector settings,
see “—Air flow selector settings” on page
301.

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If following another vehicle on a dusty
road, or driving in windy and dusty
conditions, it is recommended that the
air intake selector be temporarily set to
RECIRCULATE, which will close off the
outside passage and prevent outside
air and dust from entering the vehicle
interior.
Heating
For best results, set controls to:
Fan speed— Any setting except “OFF”
Temperature— To w a r d s WARM
(red zone)
Air intake—FRESH (outside air)
Air flow—FLOOR
Air conditioning—OFF
For quick heating, select recirculated
air for a few minutes. To keep the
windows from fogging, select fresh af-
ter the vehicle interior has been
warmed.
Press the “A/C” button on for dehumidi-
fied heating.
Choose floor/windshield air flow to heat
the vehicle interior while defrosting or
defogging the windshield. Air conditioning
For best results, set controls to:
Fan speed— Any setting except “OFF”
Temperature— To w a r d s COLD
(blue zone)
Air intake—FRESH (outside air)
Air flow—PANEL
Air conditioning—ON
For quick cooling, select recirculated
air for a few minutes.
Ventilation
For best results, set controls to:
Fan speed— Any setting except “OFF”
Temperature— To w a r d s COLD
(blue zone)
Air intake—FRESH (outside air)
Air flow—PANEL
Air conditioning—OFF
Defogging
—The inside of the windshield
For best results, set controls to:
Fan speed— Any setting except “OFF”
Temperature— To w a r d s WARM
(red zone) to heat;
COLD (blue zone) to
cool
Air flow—WINDSHIELD
Turning the air flow selector to the wind-
shield or floor/windshield position turns on
the defogging function with the purpose of
clearing the front view.
When turning the air flow selector to the
windshield or floor/windshield position, the
air intake selects FRESH automatically.
This is to clean up the front view more
quickly.
Press the “A/C” button for dehumidified
heating or cooling. This setting clears the
front view more quickly.
On humid days, do not blow cold air
on the windshield—the difference be-
tween the outside and inside tempera-
tures could make the fogging worse.

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“AUTO” button
For automatic operation of the air condi-
tioning, press the “AUTO” button. An indi-
cator light will illuminate to show that the
automatic operation mode has been se-
lected.
In the automatic operation mode, the air
conditioning selects the most suitable fan
speed, air flow, air intake and on−off of
the air conditioning according to the tem-
perature.
When you adjust the temperature selector
button to maximum cooling, “LO” will ap-
pear on the display and the air intake
mode will be automatically changed to RE-
CIRCULATE.
You may use manual controls if you want
to select your own settings.
Fan speed selector
Push the “
” (increase) or “” (de-
crease) side of the button to adjust the
fan speed.
In the automatic operation mode, the fan
speed is adjusted automatically unless you
desire another fan speed mode. “SYNC” button
Push the button to change the mode of
the temperature setting.
With the indicator on—
Simultaneous tem-
perature setting
With the indicator off— Individual temper-
ature setting
With the indicator on, the rear air condi-
tioning is turned on. However, controls on
the rear control panel cannot be used. To
cancel this function, push the “SYNC” but-
ton.
For details about the rear air conditioning,
see “Rear automatic air conditioning sys-
tem” on page 312 in this Section.
Temperature selectors
To increase the temperature, press the
“
” side. To decrease it, press the “”
side.
“LO” appears when you adjust to maxi-
mum cooling, and “HI” appears when you
adjust to maximum warming.
—“TEMP” button
With the “SYNC” button indicator on—
This button changes the temperature on
the driver side, front passenger side and
rear passenger side simultaneously. This function will be cancelled when the
“PASS TEMP” or “REAR TEMP” button is
pushed.
With the “SYNC” button indicator
off—
This button changes the temperature
on the driver side only.
—“PASS TEMP” button
This button changes the temperature on
the front passenger side only.
—“REAR TEMP” button
This button changes the temperature on
the rear passenger side only when the
rear air conditioning is turned on.
For details about the rear air conditioning,
see “Rear automatic air conditioning sys-
tem” on page 312 in this Section.
The temperature display changes between
“  C” and “ F” when the unit of the outside
temperature display is changed. (For de-
tails, see “Multi −information display” on
page 316 in Section 1 −9.)
“OFF” button
Push the button to turn off the air condi-
tioning system.

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“MODE” button (air flow selector)
Push the “MODE” button to select the
vents used for air flow.
In the automatic operation mode, the air
flow mode is selected automatically among
Panel, Bi−level, Floor and Floor/Windshield
unless you desire another air flow mode.
1. Panel— Air flows from the instrument
panel vents.
2. Bilevel— Air flows from both the floor
vents and the instrument panel vents.
3. Floor— Air flows mainly from the floor
vents.
4. Floor/Windshield— Air flows mainly
from the floor vents and windshield
vents. Windshield air flow button
When this button is pressed, air flows
mainly from the windshield vents and
turns on the defogging function with the
purpose of clearing the front view.
Pressing this button once again returns
the air flow mode to the last one used.
This button allows the air intake to select
FRESH automatically. This is to clean up
the front view more quickly.
Press the “A/C” button for dehumidified
heating or cooling. This setting clears the
front view more quickly.
For details about air flow selector settings,
see “—Air flow selector settings” on page
307.Air intake selector
Press the button to select the air source.
1. Recirculate— Recirculates the air inside
the vehicle.
2. Fresh— Draws outside air into the sys-
tem.
To prevent fogging up of the windshield,
the air intake mode may change automati-
cally to FRESH depending on the condi-
tion of the air conditioning system.
“A/C” button
To turn on the air conditioning, press the
“A/C” button. The “A/C” button indicator
will come on. To turn the air conditioning
off, press the button again.

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2004 SIENNA from Aug. ’04 Prod. (OM45422U)
If following another vehicle on a dusty
road, or driving in windy and dusty
conditions, it is recommended that the
air intake selector be temporarily set to
RECIRCULATE, which will close off the
outside passage and prevent outside
air and dust from entering the vehicle
interior.A U T O M AT I C O P E R AT I O N
Press in the “AUTO” button.
Temperature— To the desired
temperature
MANUAL OPERATION
For best results, set controls to:
Heating
Fan speed— To the desired fan speed
Temperature— Towards high temperature
Air intake—FRESH (outside air)
Air flow—FLOOR
Air conditioning—OFF
For quick heating, select recirculated
air for a few minutes. To keep the
windows from fogging, select fresh af-
ter the vehicle interior has been
warmed.
Press the “A/C” button on for dehumidi-
fied heating.
Choose floor/windshield air flow to heat
the vehicle interior while defrosting or
defogging the windshield. Air conditioning
Fan speed— To the desired fan speed
Temperature— Towards low temperature
Air intake—FRESH (outside air)
Air flow—PANEL
Air conditioning—ON
For quick cooling, select recirculated
air for a few minutes.
Ventilation
Fan speed— To the desired fan speed
Temperature— To w a r d s low temperature
Air intake—FRESH (outside air)
Air flow—PANEL
Air conditioning—OFF

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OPERATION FOR DEFOGGING
The inside of the windshield
For best results, set controls to:Fan speed— To the desired fan speed
Temperature— To w a r d s high temperature
to heat; low temperature
to cool
Air flow—WINDSHIELD
Pressing the windshield air flow button
turns on the defogging function with the
purpose of clearing the front view.
When pressing the windshield air flow but-
ton, the air intake selects FRESH auto-
matically. This is to clean up the front
view more quickly.
Press the “A/C” button for dehumidified
heating or cooling. This setting clears the
front view more quickly.
On humid days, do not blow cold air
on the windshield—the difference be-
tween the outside and inside tempera-
tures could make the fogging worse. OPERATION FOR DEFROSTING
The outside of the windshield
For best results, set controls to:
Fan speed— To the desired fan speed
Temperature— To w a r d s high temperature
Air flow—WINDSHIELD
Pressing the windshield air flow button
turns on the defrosting function with the
purpose of clearing the front view.
When pressing the windshield air flow but-
ton, the air intake selects FRESH auto-
matically. This is to clean up the front
view more quickly.
Press the “A/C” button for dehumidified
heating. This setting clears the front view
more quickly.
To heat the vehicle interior while de-
frosting the windshield, choose
floor/windshield air flow.
If air flow control is not satisfactory, check
the side vents. The side vents may be
opened or closed as shown.
Side vents

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“AUTO” button
For automatic operation of the rear air
conditioning, press the “AUTO” button. An
indicator light will illuminate to show that
the automatic operation mode has been
selected.
In the automatic operation mode, the air
conditioning selects the most suitable fan
speed and air flow according to the tem-
perature.
You may use manual controls if you want
to select your own settings.
Fan speed selectors
Push the button to select the fan speed
mode.
In the automatic operation mode, the fan
speed is adjusted automatically unless you
desire another fan speed mode.Temperature selectors
To increase the temperature, press the
“
 ” side. To decrease it, press the “ ”
side.
“LO” appears when you adjust to maxi-
mum cooling, and “HI” appears when you
adjust to maximum warming.
When “SYNC” appears on the rear tem-
perature display, rear controls cannot be
used. Use the controls on the front control
panel. To cancel this function, push the
“SYNC” button. For details about the
“SYNC” button, see “Front automatic air
conditioning system” on page 304 in this
Section.
The temperature display changes between
“  C” and “ F” when the unit of the outside
temperature display is changed. (For de-
tails, see “Multi −information display” on
page 316 in Section 1 −9.)
“REAR” button
To turn on the rear air conditioning system
using the front control panel, push the
button. To turn it off, push the button
again.
“OFF” button
Push the button to turn off the rear air
conditioning system.
Air flow selectors
Push the button to select the vents used
for air flow. 1. Panel— Air flows from the roof panel
vents.
2. Bilevel— Air flows from both the roof
panel vents and floor vent.
3. Floor— Air flows from the floor vent.