2020 Lexus GX460 cooling

GX460_OM_OM60R27U_(U)
3775-1. Using the air conditioning system and defogger
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Interior features
■Adjusting the temperature setting
Press to increase the temperature and to decrease the tempera-
ture.
If the “A/C” indicator is turned off, the system will blow ambient temperature air or
heated air.
■Adjusting the fan speed setting
Press to increase the fan speed and to decrease the fan speed.
Press the “OFF” button to turn the fan off.
■Changing the air flow mode
Select an air outlet switch.
: Air flows to the upper body
: Air flows to the upper body and feet
: Air flows to the feet
■Option control screen
Touch on the climate screen to display the option control screen. The
functions can be switched on and off.Select to set cooling and dehu-
midification function on/off
Adjust the temperature for driver
and passenger seats separately
(“DUAL” mode)/driver, passen-
ger and rear seats separately (“3-
ZONE” mode) ( P. 378)
Prevent ice from building up on
the windshield and wiper blades
(if equipped) ( P. 381)
Remove pollen from the air ( P. 381)
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GX460_OM_OM60R27U_(U)
4496-3. Do-it-yourself maintenance
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Maintenance and care
WARNING
The engine compartment contains many mechanisms and fluids that may move suddenly,
become hot, or become electrically energize d. 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 or rags, in the engine com-
partment.
●Do not smoke, cause sparks or expose an open flame to fuel or the battery. Fuel and
battery fumes are flammable.
●Be extremely cautious when working on the battery. It contains poisonous and corro-
sive sulfuric acid.
■When working near the electric cooling fans or radiator grille
Be sure the engine switch is off. With the engine switch in IGNITION ON mode, the
electric cooling fans may auto matically start to run if the air conditioning is on and/or
the coolant temperature is high. ( P. 457)
■When working on or under the vehicle
Do not get under the vehicle with just the jack supporting it.
Always use automotive jack stands or other solid supports.
■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 f ilter removed may cause excessive engine wear due to dirt
in the air.

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GX460_OM_OM60R27U_(U)6-3. Do-it-yourself maintenance
6
Maintenance and care
Engine compartment
Power steering fluid reservoir
(P. 459)
Engine oil level dipstick (P. 453)
Engine oil filler cap ( P. 454)
Brake fluid reservoir ( P. 457)
Fuse box ( P. 486)Battery
(P. 460)
Radiator ( P. 457)
Condenser ( P. 457)
Cooling fans
Engine coolant reservoir (P. 455)
Washer fluid tank ( P. 463)1
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GX460_OM_OM60R27U_(U)6-3. Do-it-yourself maintenance
■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-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 % 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 engine coolant, contact your Lexus dealer.
■If the coolant level drops within a short time of replenishing
Visually check the radiator, hoses, engine c oolant reservoir cap, radiator cap, drain cock
and water pump. If you cannot find a leak, have your Lexus dealer test the cap and check
for leaks in the cooling system.
WARNING
■When the engine is hot
Do not remove the radiator 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 straight antifreeze. The correct mixture of water and
antifreeze must be used to provide proper lubrication, corrosion protection and cool-
ing. Be sure to read the antifreeze or coolant label.
■If you spill coolant
Be sure to wash it off with water to pr event it from damage to parts or paint.

5457-2. Steps to take in an emergency
GX460_OM_OM60R27U_(U)
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When trouble arises
WARNING
■Avoiding battery fires or explosions
Observe the following precautions to preven t accidentally igniting the flammable gas
that may be emitted from the battery:
●Make sure the jumper cable is connected to the correct terminal and that it is not
unintentionally in contact with any other than the intended terminal.
●Do not allow the + and - clamps of the jump er cables to come into contact with each
other.
●Do not smoke, use matches, cigarette lighters or allow open flame near the battery.
■Battery precautions
The battery contains poisonous and corrosive acidic electrolyte, while related parts
contain lead and lead compounds. Observ e the following precautions when handling
the battery:
●When working with the battery, always wear safety glasses and take care not to allow
any battery fluids (acid) to come into cont act with 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 medical attention can be
received.
●Always wash your hands afte r handling the battery support, terminals, and other bat-
tery-related parts.
●Do not allow childre n near the battery.
NOTICE
■When handling jumper cables
When connecting the jumper cables, ensure that they do not become entangled in the
cooling fans or belt.

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GX460_OM_OM60R27U_(U)7-2. Steps to take in an emergency
If your vehicle overheats
Stop the vehicle in a safe place and tu
rn off the air conditioning system, 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 suff iciently, inspect the hoses and radiator
core (radiator) for any leaks.
Radiator
Cooling fans
If a large amount of coolant leaks,
immediately contact your Lexus
dealer.
The following may indicate that your vehicle is overheating.
●The needle of the engine coolant temperature gauge ( P. 88) enters the
red zone or a loss of engine power is experienced. (For example, the vehicle
speed does not increase.)
●Steam is coming from under the hood.
Correction procedures
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5477-2. Steps to take in an emergency
GX460_OM_OM60R27U_(U)
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When trouble arises
The coolant level is satisfactory if it is between the “F” and “L” lines on the res-
ervoir. Reservoir
“F”
“L”
Radiator cap
Add coolant if necessary.
Water can be used in an emergency if
coolant is unavailable.
Start the engine and turn the air conditio ning system on to check that the radi-
ator cooling fans operate and to check for coolant leaks from the radiator or
hoses.
The fans operate when the air conditioning system is turned on immediately after a
cold start. Confirm that the fans are operating by checking the fan sound and air flow.
If it is difficult to check these, turn the air conditioning system on and off repeatedly.
(The fans may not operate in freezing temperatures.)
If the fans are not operating:
Stop the engine immediately an d contact your Lexus dealer.
If the fans are operating:
Have the vehicle inspected at the nearest Lexus dealer.
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5487-2. Steps to take in an emergency
GX460_OM_OM60R27U_(U)
WARNING
■When inspecting under the hood of your vehicle
Observe the following precautions.
Failure to do so may result in serious injury such as burns.
●If steam is seen coming from under the h ood, do not open the hood until the steam
has subsided. The engine compartment may be very hot.
●Keep hands and clothing (especially a tie, a scarf or a muffler) away from the fans and
belts. Failure to do so may cause the hands or clothing to be caught, resulting in seri-
ous injury.
●Do not loosen the radiator cap or the cool ant reservoir cap while the engine and radi-
ator are hot. High temperature steam or coolant could spray out.
NOTICE
■When adding engine coolant
Add coolant slowly after the engine has cool ed down sufficiently. Adding cool coolant
to a hot engine too quickly can cause damage to the engine.
■To prevent damage to the cooling system
Observe the following precautions:
●Avoid contaminating the coolant with foreig n matter (such as sand or dust etc.).
●Do not use any coolant additive.