2006 GMC YUKON XL engine overheat

Engine Coolant Heater
Your vehicle may be equipped with an engine
coolant heater.
In very cold weather, 0°F (−18°C) or colder, the engine
coolant heater can help. You will get easier starting
and better fuel economy during engine warm-up.
Usually, the coolant heater should be plugged in a
minimum of four hours prior to starting your vehicle.
At temperatures above 32°F (0°C), use of the coolant
heater is not required. Your vehicle may also have
an internal thermostat in the plug end of the cord.
This will prevent operation of the engine coolant heater
when the temperature is at or above 0°F (−18°C) as
noted on the cord.
To Use the Engine Coolant Heater
1. Turn off the engine.
2. Open the hood and unwrap the electrical cord.
The cord is located on the driver’s side of the
engine compartment, near the power steering
uid reservoir.
3. Plug it into a normal, grounded 110-volt AC outlet.
{CAUTION:
Plugging the cord into an ungrounded outlet
could cause an electrical shock. Also, the
wrong kind of extension cord could overheat
and cause a re. You could be seriously
injured. Plug the cord into a properly grounded
three-prong 110-volt AC outlet. If the cord
will not reach, use a heavy-duty three-prong
extension cord rated for at least 15 amps.
4. Before starting the engine, be sure to unplug and
store the cord as it was before to keep it away
from moving engine parts. If you do not, it could
be damaged.
How long should you keep the coolant heater plugged
in? The answer depends on the outside temperature,
the kind of oil you have, and some other things.
Instead of trying to list everything here, we ask that
you contact your dealer in the area where you will
be parking your vehicle. The dealer can give you the
best advice for that particular area.
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Leaving Your Vehicle With the Engine
Running
{CAUTION:
It can be dangerous to leave your vehicle
with the engine running. Your vehicle could
move suddenly if the shift lever is not fully in
PARK (P) with the parking brake rmly set.
If you have four-wheel drive and your transfer
case is in NEUTRAL, your vehicle will be free
to roll, even if your shift lever is in PARK (P).
So be sure the transfer case is in a drive
gear — not in NEUTRAL.
And, if you leave the vehicle with the engine
running, it could overheat and even catch re.
You or others could be injured. Do not leave
your vehicle with the engine running unless
you have to.If you have to leave your vehicle with the engine running,
be sure your vehicle is in PARK (P) and the parking
brake is rmly set before you leave it. After you move
the shift lever into PARK (P), hold the regular brake pedal
down. Then, see if you can move the shift lever away
from PARK (P) without rst pulling it toward you. If you
can, it means that the shift lever was not fully locked
into PARK (P).
Torque Lock
If you are parking on a hill and you do not shift your
transmission into PARK (P) properly, the weight of
the vehicle may put too much force on the parking
pawl in the transmission. You may nd it difficult to
pull the shift lever out of PARK (P). This is called
“torque lock.” To prevent torque lock, set the parking
brake and then shift into PARK (P) properly before you
leave the driver’s seat. To nd out how, seeShifting
Into Park (P) on page 2-32.
When you are ready to drive, move the shift lever out
of PARK (P) before you release the parking brake.
If torque lock does occur, you may need to have
another vehicle push yours a little uphill to take some of
the pressure from the parking pawl in the transmission,
so you can pull the shift lever out of PARK (P).
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Anti-Lock Brake System
Warning Light
With the anti-lock brake
system, this light will come
on when you start your
engine and may stay on
for several seconds.
That’s normal. If the light doesn’t come on then, have it
xed so it will be ready to warn you if there is a problem.
If the light stays on, or comes on when you’re driving,
your vehicle needs service. You will also hear a
chime sound when the light is on steady. If the regular
brake system warning light isn’t on, you still have
brakes, but you don’t have anti-lock brakes. If the
regular brake system warning light is also on you don’t
have anti-lock brakes and there’s a problem with
your regular brakes. In addition to both lights, you will
also hear a chime sound on the rst occurrence of
a problem and each time the vehicle is shut off and
then restarted. SeeBrake System Warning Light
on page 3-42.
Engine Coolant Temperature Gage
This gage shows the engine coolant temperature.
It also provides an indicator of how hard your vehicle is
working. During a majority of the operation, the gage
will read 210°F (100°C) or less. If you are pulling a load
or going up hills, it is normal for the temperature to
uctuate and approach the 250°F (122°C) mark. If the
gage reaches the 260°F (125°C) mark, it indicates
that the cooling system is working beyond its capacity.
SeeEngine Overheating on page 5-28.
United StatesCanada
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DRIVER DOOR AJAR
If the driver’s door is not fully closed, this message
will appear on the display and you will hear a chime.
Stop and turn off the vehicle, check the door for
obstacles, and close the door again. Check to see if the
message still appears on the DIC. Pressing any of the
four DIC buttons will acknowledge the message and clear
it from the DIC display. If your vehicle does not have the
four DIC buttons, pressing the trip odometer reset stem
will acknowledge the message and clear it from the
DIC display.
ENGINE COOLANT HOT
If the cooling system temperature gets hot, this message
will appear in the DIC. Turn off the air conditioning. If the
message is still on, or if the engine coolant temperature
gage continues to rise, pull the vehicle over when it is
safe to do so. SeeEngine Coolant Temperature Gage on
page 3-43for more information. Stop the vehicle and let
the engine idle in PARK (P) for a few minutes to allow the
coolant to reach a safe temperature. This message will
clear when the coolant temperature drops to a safe
operating temperature. Pressing any of the four DIC
buttons will acknowledge the message and clear it
from the DIC display. If your vehicle does not have the
four DIC buttons, pressing the trip odometer reset stem
will acknowledge the message and clear it from the
DIC display.
ENGINE OVERHEATED
Notice:If you drive your vehicle while the engine
is overheating, severe engine damage may occur.
If an overheat warning appears on the instrument
panel cluster and/or DIC, stop the vehicle as soon as
possible. Do not increase the engine speed above
normal idling speed. SeeEngine Overheating
on page 5-28for more information.
If the engine cooling system reaches unsafe
temperatures for operation, this message will appear in
the DIC and you will hear a chime. Stop and turn off
the vehicle as soon as it is safe to do so to avoid severe
damage. This message will clear when the engine
has cooled to a safe operating temperature.
FUEL LEVEL LOW
If the fuel level is low, this message will appear on the
DIC and you will hear a chime. Refuel as soon as
possible. Pressing any of the four DIC buttons will
acknowledge the message and clear it from the
DIC display. If your vehicle does not have the four DIC
buttons, pressing the trip odometer reset stem will
acknowledge the message and clear it from the DIC
display. SeeFuel Gage on page 3-51,Fuel on page 5-4,
andLow Fuel Warning Light on page 3-51.
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KEYFOB X BATTERY LOW
If a remote keyless entry transmitter battery is low,
this message will appear on the DIC. The battery
needs to be replaced in the transmitter. See “Battery
Replacement” underRemote Keyless Entry System
Operation on page 2-5. Pressing any of the four DIC
buttons will acknowledge the message and clear it from
the DIC display. If your vehicle does not have the
four DIC buttons, pressing the trip odometer reset stem
will acknowledge the message and clear it from the
DIC display.
LEFT REAR DOOR AJAR
If the driver’s side rear door is not fully closed, this
message will appear on the display and you will hear a
chime. Stop and turn off the vehicle, check the door
for obstacles, and close the door again. Check to see if
the message still appears on the DIC. Pressing any
of the four DIC buttons will acknowledge the message
and clear it from the DIC display. If your vehicle does not
have the four DIC buttons, pressing the trip odometer
reset stem will acknowledge the message and clear
it from the DIC display.
LOW COOLANT LEVEL
Notice:Engine damage from running your engine
without coolant is not covered by your warranty.
See “Overheated Engine Protection Operating
Mode” in the Index for information on driving to a
safe place in an emergency.
If your vehicle has a low coolant level sensor, this
message will appear on the DIC if the engine coolant
level is low. Adding coolant will clear the message.
SeeCooling System on page 5-30. Pressing any of the
four DIC buttons will acknowledge the message and
clear it from the DIC display. If your vehicle does
not have the four DIC buttons, pressing the trip
odometer reset stem will acknowledge the message
and clear it from the DIC display.
OIL LIFE RESET
This message will appear on the DIC for about
10 seconds after resetting the change engine oil
message. See “Engine Oil Life System” underDIC
Operation and Displays on page 3-53andEngine Oil
on page 5-15for more information.
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OIL PRESSURE LOW
Notice:If you drive your vehicle while the engine
oil pressure is low, severe engine damage may
occur. If a low oil pressure warning appears on the
Driver Information Center (DIC), stop the vehicle
as soon as possible. Do not drive the vehicle until
the cause of the low oil pressure is corrected.
SeeEngine Oil on page 5-15for more information.
If low oil pressure levels occur, this message will
be displayed on the DIC and a chime will sound.
Stop the vehicle as soon as safely possible and do not
operate it until the cause of the low oil pressure has
been corrected. Check your oil as soon as possible and
have your vehicle serviced by your GM dealer. See
Engine Oil on page 5-15.
PASSENGER DOOR AJAR
If the passenger’s door is not fully closed, this message
will appear on the display and you will hear a chime.
Stop and turn off the vehicle, check the door for
obstacles, and close the door again. Check to see if the
message still appears on the DIC. Pressing any of
the four DIC buttons will acknowledge the message and
clear it from the DIC display. If your vehicle does not
have the four DIC buttons, pressing the trip odometer
reset stem will acknowledge the message and clear
it from the DIC display.
REAR ACCESS OPEN
If the liftgate is open while the ignition is in RUN, this
message will appear on the DIC and you will hear
a chime. Turn off the vehicle and check the liftgate.
Restart the vehicle and check for the message on the
DIC display. Pressing any of the four DIC buttons
will acknowledge the message and clear it from the
DIC display. If your vehicle does not have the four DIC
buttons, pressing the trip odometer reset stem will
acknowledge the message and clear it from the
DIC display.
REDUCED ENGINE POWER
This message is displayed when the cooling system
temperature gets too hot and the engine further enters
the engine coolant protection mode. SeeEngine
Overheating on page 5-28for further information.
REPLACE LIFTGATE FUSE
This message will be displayed if the liftgate lock
malfunctions and/or the liftgate fuse blows. For more
information on fuses, seeFuses and Circuit Breakers on
page 5-106. If the message returns after replacing the
fuse, see your GM dealer for service.
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There are several conditions that can cause this
message to appear.
One condition is overheating, which could occur if
StabiliTrak®activates continuously for an extended
period of time.
The message will also be displayed if the brake
system warning light is on. SeeBrake System
Warning Light on page 3-42.
The message could be displayed if the stability
system takes longer than usual to complete its
diagnostic checks due to driving conditions.
If an engine or vehicle related problem has been
detected and the vehicle needs service, the
message will appear. See your GM dealer.
The message will also appear if the vehicle is
shifted into 4LO.
The message will turn off as soon as the conditions
that caused the message to be displayed are no longer
present.
TIGHTEN FUEL CAP
If the vehicle’s fuel cap is not tightened properly, this
message may appear along with the check engine light
on the instrument panel cluster. SeeMalfunction
Indicator Lamp on page 3-46. Reinstall the fuel cap
fully. SeeFilling the Tank on page 5-8. The diagnostic
system can determine if the fuel cap has been left off or
improperly installed. A loose or missing fuel cap will
allow fuel to evaporate into the atmosphere. A few
driving trips with the cap properly installed should turn
this light and message off.
TRACTION ACTIVE
When the traction control system has detected that
any of the vehicle’s wheels are slipping, the traction
control system will activate and this message will appear
on the DIC. SeeStabiliTrak
®System on page 4-9for
more information.
TRACTION SYS (System) LIMITED
If the brake traction control system activates constantly
or if the brakes have heated up due to high-speed
braking, brake traction control will be disabled and the
TRACTION SYS LIMITED message will be displayed.
The system will return to normal operation after the
brakes have cooled. SeeStabiliTrak
®System on
page 4-9for more information.
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TRANS (Transmission) HOT IDLE
ENGINE
Notice:If you drive your vehicle while the
transmission uid is overheating and the
transmission temperature warning is displayed on
the instrument panel cluster and/or DIC, you
can damage the transmission. This could lead to
costly repairs that would not be covered by
your warranty. Do not drive your vehicle with
overheated transmission uid or while the
transmission temperature warning is displayed.
If the transmission uid in the vehicle gets hot,
this message will appear on the DIC along with a
continuous chime. Driving with the transmission uid
temperature high can cause damage to the vehicle.
Stop the vehicle and let it idle to allow the transmission
to cool. This message will clear and the chime will
stop when the uid temperature reaches a safe level.
SeeTransmission Temperature Gage on page 3-44.
TRANSMISSION HOT
Notice:If you drive your vehicle while the
transmission uid is overheating and the
transmission temperature warning is displayed on
the instrument panel cluster and/or DIC, you
can damage the transmission. This could lead to
costly repairs that would not be covered by
your warranty. Do not drive your vehicle with
overheated transmission uid or while the
transmission temperature warning is displayed.
If the transmission uid temperature becomes high,
this message will appear on the DIC.
When the transmission enters the protection mode,
you may notice a change in the transmission shifting
patterns. When the transmission uid temperature
returns to normal, the display will turn off and the
transmission shifting patterns will return to normal.
If the vehicle has the Tow/Haul mode, use this feature if
the transmission is operating at higher temperatures
and/or the following situations exist, which can cause the
transmission to operate at higher temperatures:
Towing a trailer
Hot outside air temperatures
Hauling a large or heavy load
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