cooling TOYOTA 4RUNNER 2003 N210 / 4.G Owners Manual

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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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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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“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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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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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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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

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Keep your engine in good running
order. Malfunctions in the engine
electrical system, electronic ignition
system/distributor ignition system
or fuel systems could cause an ex-
tremely high threeway catalytic
converter temperature.
 If the engine becomes difficult to
start or stalls frequently, take your
vehicle in for a checkup as soon
as possible. Remember, your Toyota
dealer knows your vehicle and its
threeway catalytic converter sys-
tem best.
 To ensure that the threeway cata-
lytic converter and the entire emis-
sion control system operate proper-
ly, your vehicle must receive the
periodic inspections required by the
Toyota Maintenance Schedule. For
scheduled maintenance information,
refer to the “Scheduled Maintenance
Guide” or “Owner ’s Manual Supple-
ment”.CAUTION
Avoid inhaling the engine exhaust.
It contains carbon monoxide, which
is a colorless and odorless gas. It
can cause unconsciousness or even
death.
Make sure the exhaust system has
no holes or loose connections. The
system should be checked from
time to time. If you hit something,
or notice a change in the sound of
the exhaust, have the system
checked immediately.
Do not run the engine in a garage
or enclosed area except for the
time needed to drive the vehicle in
or out. The exhaust gases cannot
escape, making this a particularly
dangerous situation.
Do not remain for a long time in a
parked vehicle with the engine run-
ning. If it is unavoidable, however,
do so only in an unconfined area
and adjust the heating or cooling
system to force outside air into the
vehicle.
Keep the back door and back win-
dow closed while driving. An open
or unsealed back door and back
window, may cause exhaust gases
to be drawn into the vehicle.
To allow proper operation of your
vehicle’s ventilation system, keep
the inlet grilles in front of the wind-
shield clear of snow, leaves, or oth-
er obstructions.
If you smell exhaust fumes in the
vehicle, drive with the windows
open and the back door and back
window closed. Have the cause im-
mediately located and corrected.
Engine exhaust cautions

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FUNCTIONS OF ENGINE OIL
Engine oil has the primary functions of
lubricating and cooling the inside of the
engine, and plays a major role in main-
taining the engine in proper working order.
ENGINE OIL CONSUMPTION
It is normal that an engine should con-
sume some engine oil during normal
engine operation. The causes of oil
consumption in a normal engine are as
follows.
Oil is used to lubricate pistons, piston
rings and cylinders. A thin film of oil
is left on the cylinder wall when a pis-
ton moves downwards in the cylinder.
High negative pressure generated when
the vehicle is decelerating sucks some
of this oil into the combustion chamber.
This oil as well as some part of the oil
film left on the cylinder wall is burned
by the high temperature combustion
gases during the combustion process.
Oil is also used to lubricate the stems
of the intake valves. Some of this oil
is sucked into the combustion chamber
together with the intake air and is
burned along with the fuel. High tem-
perature exhaust gases also burn the
oil used to lubricate the exhaust valve
stems.
The amount of engine oil consumed de-
pends on the viscosity of the oil, the
quality of the oil and the conditions the
vehicle is driven under.
More oil is consumed by highspeed driv-
ing and frequent acceleration and decel-
eration.
A new engine consumes more oil, since
its pistons, piston rings and cylinder walls
have not become conditioned.
Oil consumption: Max. 1.0 L per 1000
km (1.1 qt./600 miles, 0.9 lmp. qt./600
miles)
When judging the amount of oil con-
sumption, note that the oil may become
diluted and make it difficult to judge
the true level accurately. As an example, if a vehicle is used for
repeated short trips, and consumes a nor-
mal amount of oil, the dipstick may not
show any drop in the oil level at all, even
after 1000 km (600 miles) or more. This
is because the oil is gradually becoming
diluted with fuel or moisture, making it
appear that the oil level has not changed.
The diluting ingredients evaporate out
when the vehicle is then driven at high
speeds, as on an expressway, making it
appear that oil is excessively consumed
after driving at high speeds.
IMPORTANCE OF ENGINE OIL LEVEL
CHECK
One of the most important points in prop-
er vehicle maintenance is to keep the en-
gine oil at the optimum level so that oil
function will not be impaired. Therefore, it
is essential that the oil level be checked
regularly. Toyota recommends that the oil
level be checked every time you refuel
the vehicle.
NOTICE
Failure to check the oil level regularly
could lead to serious engine trouble
due to insufficient oil.
Facts about engine oil
consumption