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GX460_OM_OM60M73U_(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 sufficiently, 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. 7 9 ) e n t e r s t h e
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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5577-2. Steps to take in an emergency
GX460_OM_OM60M73U_(U)
7
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 conditioning 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 oper ating by checking the fan sound and air flow.
If it is difficult to check th ese, 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 and contact your Lexus dealer.
If the fans are operating:
Have the vehicle inspected at the nearest Lexus dealer.
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5587-2. Steps to take in an emergency
GX460_OM_OM60M73U_(U)
CAUTION
■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 hood, 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 coolant 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 cooled 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 foreign matter (such as sand or dust etc.).
●Do not use any coolant additives.