2018 TOYOTA TUNDRA cooling

4126-1. Using the air conditioning system
Manual air conditioning system
■Adjusting the temperature setting
To adjust the temperature set-
ting, turn the temperature con-
trol dial clockwise (warm) or
counterclockwise (cool).
If is not pressed, the
system will blow ambient tem-
perature air or heated air.
For quick cooling, turn the tem-
perature control dial to the “MAX
A/C” position.
The air conditioning will automatically turn on and the air int ake selector
will be set to recirculated air mode.
: If equipped
Air conditioning controls

4176-1. Using the air conditioning system
6
Interior features
■Fogging up of the windows
●The windows will easily fog up when the humidity in the vehicle is high.
Turning on will dehumidify the air from the outlets and defog the
windshield effectively.
● If you turn off, the windows may fog up more easily.
● The windows may fog up if the recirculated air mode is used.
■ Outside/recirculated air mode
When driving on dusty roads such as tunnels or in heavy traffic, set the out-
side/recirculated air mode button to the recirculated air mode. This is effective
in preventing outside air from entering the vehicle interior. During cooling
operation, setting the recirculated air mode will also cool the vehicle interior
effectively.
■ When the outside temperature exceeds 75 F (24 C) and air conditioning
system is on
● In order to reduce the air conditioning power consumption, the air condition-
ing system may switch to recirculated air mode automatically. This may also
reduce fuel consumption.
● Recirculated air mode is selected as a default mode when the en gine switch
is in the “ON” position.
● It is possible to switch to outside air mode at any time by pre ssing .
■ When the outside tempera ture falls to nearly 32F (0 C)
The dehumidification function may not operate even when is
pressed.
■ Ventilation and air conditioning odors
●To let fresh air in, set the air conditioning system to the out side air mode.
● During use, various odors from inside and outside the vehicle m ay enter into
and accumulate in the air conditioning system. This may then ca use odor to
be emitted from the vents.
● To reduce potential odors from occurring:
It is recommended that the air conditioning system be set to ou tside air
mode prior to turning the vehicle off.
■ Air conditioning filter
P. 513

4246-1. Using the air conditioning system
■Using automatic mode
Fan speed is adjusted automatically according to the temperatur e setting and
the ambient conditions.
Therefore, the fan may stop for a while until warm or cool air is ready to flow
immediately after is pressed.
■ Fogging up of the windows
●The windows will easily fog up when the humidity in the vehicle is high.
Turning on will dehumidify the air from the outlets and defog the
windshield effectively.
● If you turn off, the windows may fog up more easily.
● The windows may fog up if the recirculated air mode is used.
■ Outside/recirculated air mode
●When driving on dusty roads such as tunnels or in heavy traffic, set the out-
side/recirculated air mode button to the recirculated air mode. This is effec-
tive in preventing outside air from entering the vehicle interi or. During
cooling operation, setting the recirculated air mode will also cool the vehicle
interior effectively.
● Outside/recirculated air mode may automatically switch dependin g on the
temperature setting or the inside temperature.
■ When the outside temperature exceeds 75°F (24°C) and the air co ndition-
ing system is on
● In order to reduce the air conditioning power consumption, the air condition-
ing system may switch to recirculated air mode automatically. This may also
reduce fuel consumption.
● Recirculated air mode is selected as a default mode when the en gine switch
is in the “ON” position.
● It is possible to switch to outside air mode at any time by pre ssing .
■ When the outside tempera ture falls to nearly 32F (0 C)
The dehumidification function may not operate even when is selected.

4837-3. Do-it-yourself maintenance
7
Maintenance and care
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.
■When working on the engine compartment
● Keep hands, clothing and tools away from the moving fan and eng ine
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 r ags, in the
engine compartment.
● Do not smoke, cause sparks or expose an open flame to fuel or t he 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 cooling fan or radiator grille
Be sure the engine switch is off.
With the engine switch in the “ON” position, the electric cooli ng fan may
automatically start to run if the air conditioning is on and/or the coolant tem-
perature is high. ( P. 490)
■ Safety glasses
Wear safety glasses to prevent flying or falling material, fluid spray, etc.,
from getting in your eyes.
NOTICE
■If you remove the air cleaner filter
Driving with the air cleaner filter removed may cause excessive engine wear
due to dirt in the air.

4857-3. Do-it-yourself maintenance
7
Maintenance and care
Engine compartment
Washer fluid tank (P. 494)
Engine oil level dipstick ( P. 486)
Engine coolant reservoir ( P. 488)
Engine oil filler cap ( P. 487)
Brake fluid reservoir ( P. 490) Fuse box (
P. 518)
Battery ( P. 492)
Radiator ( P. 490)
Cooling fan
Condenser ( P. 490)
Power steering fluid reservoir ( P. 491)1
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5
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9
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4897-3. Do-it-yourself maintenance
7
Maintenance and care
■Coolant selection
Only use “Toyota Super Long Life Coolant” or a similar high quality ethylene
glycol based non-silicate, non-amine, non-nitrite, and non-bora te coolant with
long-life hybrid organic acid technology.
U.S.A.:
“Toyota Super Long Life Coolant” is a mixture of 50% coolant and 50% deion-
ized water. (Minimum temperature: -31 F [-35 C])
Canada:
“Toyota Super Long Life Coolant” is a mixture of 55% coolant and 45% deion-
ized water. (Minimum temperature: -44 F [-42 C])
For more details about coolant, contact your Toyota dealer.
■ If the coolant level drops within a short time of replenishing
Visually check the radiator, hoses, engine coolant reservoir ca p, 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.
WARNING
■ When the engine is hot
Do not remove the radiator cap.( P. 587)
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 straight antifreeze. The cor rect 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 p arts or paint.

5848-2. Steps to take in an emergency
WARNING
■Avoiding battery fires or explosions
Observe the following precautions to prevent accidentally ignit ing the flam-
mable gas that may be emitted from the battery:
● Make sure each jumper cable is connected to the correct terminal and that
it is not unintentionally in contact with any other than the in tended terminal.
● Do not allow the + and - clamps of the jumper cables to come into contact
with each other.
● Do not smoke, use matches, cigarette lighters or allow open fla me near
the battery.
■ Battery precautions
The battery contains poisonous and corrosive acidic electrolyte , while
related parts contain lead and lead compounds. Observe the foll owing pre-
cautions when handling the battery:
● When working with the battery, always wear safety glasses and t ake care
not to allow any battery fluids (acid) to come into contact wit h skin, clothing
or the vehicle body.
● Do not lean over the battery.
● In the event that battery fluid comes into contact with the skin or eyes,
immediately wash the affected area with water and seek medical attention.
Place a wet sponge or cloth over the affected area until medica l attention
can be received.
● Always wash your hands after handling the battery support, term inals, and
other battery-related parts.
● Do not allow children near the battery.
NOTICE
■When handling jumper cables
When connecting the jumper cables, ensure that they do not beco me entan-
gled in the cooling fan or belt.

585
8
When trouble arises
8-2. Steps to take in an emergency
If your vehicle overheats
●The needle of the engine coolant temperature gauge ( P. 9 5 )
enters the red zone or a loss of engine power is experienced. ( For
example, the vehicle speed does not increase.)
● “ENGINE COOLANT OVERTEMP” is shown on the multi-informa-
tion display.
● Steam comes out f rom under the hood.
Stop the vehicle in a safe place and turn off the air condition ing sys-
tem, and then stop the engine.
If you see steam:
Carefully lift the hood after the steam subsides.
If you do not see steam:
Carefully lift the hood.
After the engine has cooled
down sufficiently, inspect the
hoses and radiator core (radia-
tor) for any leaks. Radiator
Cooling fan
If a large amount of coolant leaks,
immediately contact your Toyota
dealer.
The following may indicate that your vehicle is overheating:
Correction procedures
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