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If you get the overheat warning with no sign of steam,
try this for a minute or so:
1. In heavy traffic, let the engine idle in NEUTRAL (N)
while stopped. If it is safe to do so, pull off the road,
shift to PARK (P) or NEUTRAL (N) and let the
engine idle.
2. Set the climate controls to the highest heat setting
and fan speed and open the windows as necessary.
If you no longer have the overheat warning, you
can drive. Just to be safe, drive slower for about
10 minutes. If the warning does not come back on,
you can drive normally.
If the warning continues, pull over, stop, and park your
vehicle right away.
If there is still no sign of steam, idle the engine for
three minutes while you are parked. If you still have the
warning, turn off the engine and get everyone out of
the vehicle until it cools down. Also, see “Overheated
Engine Protection Operating Mode” later in this section.
You may decide not to lift the hood but to get service
help right away.Overheated Engine Protection
Operating Mode
This operating mode allows your vehicle to be driven to
a safe place in an emergency situation. If an overheated
engine condition exists and the DIC message ENGINE
HOT, STOP ENGINE is displayed, 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. Driving extended miles (km) 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 6-16.
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Cooling System
When you decide it is safe to lift the hood, here is what
you will see:
A. Electric Engine Cooling Fan
B. Coolant Surge Tank with Pressure Cap{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 surge tank is boiling,
do not do anything else until it cools down. The vehicle
should be parked on a level surface.
A low coolant level should be indicated by a LOW
COOLANT message on the Driver Information
Center (DIC). If it is, 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.
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How to Add Coolant to the Coolant
Surge Tank
If you have not found a problem yet, check to see if
coolant is visible in the surge tank. If coolant is visible
but the coolant level is not at the FULL COLD mark
on the front of the coolant surge tank, add a 50/50
mixture of clean, drinkable water and DEX-COOL
®
coolant at the coolant surge tank, but be sure the cooling
system, including the coolant surge tank pressure
cap, is cool before you do it. SeeEngine Coolant on
page 6-24for more information.
If no coolant is visible in the surge tank, add coolant as
follows:
{CAUTION:
Steam and scalding liquids from a hot cooling
system can blow out and burn you badly. They
are under pressure, and if you turn the coolant
surge tank pressure cap — even a little — they
can come out at high speed. Never turn the
CAUTION: (Continued)
CAUTION: (Continued)
cap when the cooling system, including the
coolant surge tank pressure cap, is hot.
Wait for the cooling system and coolant surge
tank pressure cap to cool if you ever have to
turn the pressure cap.
{CAUTION:
Adding only plain water to the cooling system
can be dangerous. Plain water, or some other
liquid such as alcohol, can boil before the
proper coolant mixture will. The vehicle’s
coolant warning system is set for the proper
coolant mixture. With plain water or the
wrong mixture, the engine could get too hot
but you would not get the overheat warning.
The engine could catch re and you or others
could be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant.
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