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Overheated Engine Protection
Operating Mode
This emergency operating mode allows your vehicle to be
driven to a safe place in an emergency situation. If an
overheated engine condition exists, an overheat
protection mode which alternates ring groups of
cylinders helps prevent engine damage. In this mode, you
will notice a signi cant loss in power and engine
performance. The temperature gage will indicate an
overheat condition exists. Driving extended miles (km)
and/or towing a trailer in the overheat protection mode
should be avoided.
Notice:After driving in the overheated engine
protection operating mode, to avoid engine damage,
allow the engine to cool before attempting any repair.
The engine oil will be severely degraded. Repair the
cause of coolant loss, change the oil and reset the oil
life system. SeeEngine Oil on page 5-15.
Cooling System
When you decide it is safe to lift the hood, here is what
you will see:
A. Radiator Pressure Cap
B. Electric Engine Cooling Fans
C. Coolant Recovery Tank3.5L V6 Engine
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A. Radiator Pressure Cap
B. Electric Engine Cooling Fans
C. Coolant Recovery Tank
{CAUTION:
An electric engine cooling fan under the hood
can start up even when the engine is not
running and can injure you. Keep hands,
clothing and tools away from any underhood
electric fan.
If the coolant inside the coolant recovery tank is boiling,
do not do anything else until it cools down. The
vehicle should be parked on a level surface.
The coolant level should be at or above the full cold
mark. If it is not, you may have a leak at the pressure
cap or in the radiator hoses, heater hoses, radiator,
water pump, or somewhere else in the cooling system. 3.9L V6 Engine
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How to Add Coolant to the Coolant
Recovery Tank
If you have not found a problem yet, but the coolant
level is not at or above the full cold mark, add a
50/50 mixture of clean, drinkable water and DEX-COOL
®
engine coolant at the coolant recovery tank. See
Engine Coolant on page 5-24for more information.
{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can boil
before the proper coolant mixture will. Your
vehicle’s coolant warning system is set for the
proper coolant mixture. With plain water or the
wrong mixture, your engine could get too hot
but you would not get the overheat warning.
Your engine could catch re and you or others
could be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant.
Notice:In cold weather, water can freeze and crack
the engine, radiator, heater core and other parts.
Use the recommended coolant and the proper
coolant mixture.
When the coolant in the coolant recovery tank is at or
above the full cold mark, start your vehicle.
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