2003 TOYOTA 4RUNNER cooling

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Idling for a long period with the air
conditioning on in stopandgo 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 282 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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“AUTO” button
For automatic operation of the air condi-
tioning, push 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 onoff of
the air conditioning according to the tem-
perature.
When you push the “AUTO” button with
the air intake mode at FRESH, internal
circulation may be applied for maximum
cooling.
You may use manual controls if you want
to select your own settings.
To turn off the automatic operation, push
the “OFF” button.
Fan speed selector
Select the mode button you desire to ad-
just the fan speed and push it. An indica-
tor light will illuminate to show which fan
speed mode is being selected.
In automatic operation, you do not have
to adjust the fan speed unless you desire
another fan speed mode. Temperature selector
To increase the temperature, push the
“UP” side, to decrease it, push the
“DOWN” side.
“LO” appears when you adjust to maxi-
mum cooling, and “HI” appears when you
adjust to maximum warming.
“OFF” button
Push the “OFF” button to turn off the air
conditioning system.
Air flow selector
Push one of the buttons to select the
vents used for air flow. An indicator light
will illuminate to show which air flow
mode is being selected.
In automatic operation, you do not have
to select the air flow unless you desire
another air flow mode.
1. Panel— Air flows from the instrument
panel vents and rear vents.
2. Bilevel— Air flows from both the floor
vents, the instrument panel vents and
rear vents.
3. Floor— Air flows mainly from the floor
vents.

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2003 4RUNNER from Apr. ’03 Prod. (OM 35820U)
4. Floor/Windshield—Air flows mainly
from the floor vents and windshield
vents.
5. Windshield— Air flows mainly from the
windshield vents.
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.
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” described
below.
Air intake selector
Push the button to select the air source.
An indicator light will illuminate to show
which the air source is being selected.
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, push the
“A/C” button. The
“A/C” button indicator
will come on. To turn the air conditioning
off, push the button again.
If the “A/C” button indicator flashes, there
is a problem in the air conditioning system
and the air conditioning automatically
shuts off. If this happens, take your ve-
hicle to a Toyota dealer for service.

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2003 4RUNNER from Apr. ’03 Prod. (OM 35820U)
“AUTO” button
For automatic operation of the air condi-
tioning, push 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 onoff of
the air conditioning according to the tem-
perature.
When you push the “AUTO” button with
the air intake mode at FRESH, internal
circulation may be applied for maximum
cooling.
You may use manual controls if you want
to select your own settings.
To turn off the automatic operation, push
the “OFF” button.
Fan speed selector
Select the mode button you desire to ad-
just the fan speed and push it. An indica-
tor light will illuminate to show which fan
speed mode is being selected.
In automatic operation, you do not have
to adjust the fan speed unless you desire
another fan speed mode. Temperature selector
To increase the temperature, push the “
”
side, to decrease it, push the “ ” side.
“LO” appears when you adjust to maxi-
mum cooling, and “HI” appears when you
adjust to maximum warming.
“DUAL” button
This button is used to set the tempera-
tures independently for the driver ’s seat
and front passenger seat.
Pushing the button changes the mode
from independent and linked.
Independent mode: Temperatures can be
set independently for the driver ’s seat and
front passenger ’s seat. An indicator light
will illuminated to show that the indepen-
dent mode has been selected.
Linked mode: The same temperature is
set for the driver’s seat and front passen-
ger ’s seat.
When the temperature for the front pas-
senger ’s seat is changed in linked mode,
the mode is changed automatically to in-
dependent mode.
“OFF” button
Push the “OFF” button to turn off the air
conditioning system.
Air flow selector
Push one of the buttons to select the
vents used for air flow. An indicator light
will illuminate to show which air flow
mode is being selected.
In automatic operation, you do not have
to select the air flow unless you desire
another air flow mode.

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2003 4RUNNER from Apr. ’03 Prod. (OM 35820U)
1. Panel—Air flows from the instrument
panel vents and rear vents.
2. Bilevel— Air flows from both the floor
vents, the instrument panel vents and
rear vents.
3. Floor— Air flows mainly from the floor
vents.
4. Floor/Windshield— Air flows mainly
from the floor vents and windshield
vents.
5. Windshield— Air flows mainly from the
windshield vents.
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.
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” described
below.
Air intake selector
Push the button to select the air source.
An indicator light will illuminate to show
which the air source is being selected.
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.

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2003 4RUNNER from Apr. ’03 Prod. (OM 35820U)
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 as follows:
For automatic operation—
Press in the “AUTO” button.
Temperature— To the desired
temperature
Air intake—FRESH (outside air)
Air conditioning—OFF
For manual operation—
Fan speed— To the desired fan speed
Temperature— To w a r d s WARM
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 war-
med.
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 as follows:
For automatic operation—
Press in the “AUTO” button.
Temperature— To the desired
temperature
Air intake—FRESH (outside air)
Air conditioning—ON
For manual operation—
Fan speed— To the desired fan speed
Temperature— To w a r d s COLD
Air intake—FRESH (outside air)
Air flow—PANEL
Air conditioning—ON
For quick cooling, select recirculated
air for a few minutes.

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Ventilation
For best results, set controls as follows:
For automatic operation—
Press in the “AUTO” button.
Temperature— Towards low temperature
Air intake—FRESH (outside air)
Air conditioning—OFF
For manual operation—
Fan speed— To the desired fan speed
Temperature— To w a r d s COLD
Air intake—FRESH (outside air)
Air flow—PANEL
Air conditioning—OFF
Defogging and defrosting
—The inside of the windshield
For best results, set controls as follows:
—For automatic operation
Temperature— To w a r d s high temperature
to heat; low temperature
to cool
Air intake—FRESH (outside air)
Air flow—WINDSHIELD
—For manual operation
Fan speed— To the desired fan speed
Temperature— To w a r d s high temperature
to heat; low temperature
to cool
Air intake—FRESH (outside air)
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.
If you want to return the setting to RE-
CIRCULATE mode, press the air intake
selector button once again. 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.
—The outside of the windshield
For best results, set controls as follows:
—For automatic operation
Temperature— Towards high temperature
Air intake—FRESH (outside air)
Air flow—WINDSHIELD
—For manual operation
Fan speed— To the desired fan speed
Temperature— Towards high temperature
Air intake—FRESH (outside air)
Air flow—WINDSHIELD

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2003 4RUNNER from Apr. ’03 Prod. (OM 35820U)
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.
If you want to return the setting to RE-
CIRCULATE mode, press the air intake
selector button once again.
Press the “A/C” button for dehumidified
heating or cooling. This setting clears the
front view more quickly.
To heat the vehicle interior while de-
frosting the windshield, choose
floor/windshield air flow.Center vents
Side vents
Rear vents
If air flow control is not satisfactory, check
the instrument panel vents and rear vents.
The instrument panel vents and rear vents
may be opened or closed as shown.
Instrument panel and rear
vents