2005 GMC SIERRA DENALI 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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Shifting Into Park (P)
{CAUTION:
It can be dangerous to get out of your vehicle
if the shift lever is not fully in PARK (P) with
the parking brake rmly set. Your vehicle can
roll. If you have left the engine running, the
vehicle can move suddenly. You or others
could be injured. To be sure your vehicle will
not move, even when you are on fairly level
ground, use the steps that follow. If you are
pulling a trailer, seeTowing a Trailer on
page 4-52.
1. Hold the brake pedal down with your right foot and
set the parking brake with your left foot.
2. Move the shift lever into PARK (P) by pulling the
shift lever toward you and moving it up as far as it
will go.
3. Turn the ignition key to LOCK.
4. Remove the key and take it with you. If you can
leave your vehicle with the ignition key in your
hand, your vehicle is in PARK (P).
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.
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.
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).
2-25

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 5-26.
Transmission Temperature Gage
Your vehicle may be equipped with a transmission
temperature gage.
When your ignition is on, the gage shows the
temperature of the transmission uid. The normal
operating range is from 180°F (82°C) to about
200°F (93°C).
At approximately 265°F (130°C), the message center
will display a TRANSMISSION HOT message and
the transmission will enter a transmission protection
mode. When the transmission enters the protection
mode, you may notice a change in the transmission
shifting patterns. The transmission will return to normal
shifting patterns when the transmission uid temperature
falls below 260°F (127°C). United States
CanadaUnited StatesCanada
3-34

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, if equipped, will acknowledge the
message and clear it from the DIC display. If your
vehicle is not equipped with 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. Stop the vehicle and let the
engine idle in PARK (P) to allow the coolant to reach a
safe temperature. This message will clear when the
coolant temperature drops to safe operating
temperature. Also, pressing any of the four DIC buttons,
if equipped, will acknowledge the message and clear
it from the DIC display. If your vehicle is not equipped
with the four DIC buttons, pressing the trip odometer
reset stem will acknowledge the message and clear it
from the DIC display.
ENGINE OVERHEATED
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.
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 5-26for more information.
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. The message will be displayed for 10 seconds
at the start of each ignition cycle when the fuel level is
low. Pressing any of the four DIC buttons, if equipped, will
acknowledge the message and clear it from the DIC
display. If your vehicle is not equipped with 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 3-41andFuel on
page 5-5.
3-48

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 2-4. Pressing any of the four DIC buttons, if
equipped, will acknowledge the message and clear it
from the DIC display. If your vehicle is not equipped with
the four DIC buttons, pressing the trip odometer reset
stem will acknowledge the message and clear it from the
DIC display.
LOW COOLANT LEVEL
If your vehicle is equipped with 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. See
Cooling System on page 5-29. Pressing any of the
four DIC buttons, if equipped, will acknowledge the
message and clear it from the DIC display. If your vehicle
is not equipped with the four DIC buttons, pressing the
trip odometer reset stem will acknowledge the message
and clear it from the DIC display.
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.
OIL LIFE RESET
This message will appear on the display for about
10 seconds after resetting the change engine oil
message. See “Engine Oil Life System” underDIC
Operation and Displays on page 3-43andEngine Oil on
page 5-14for more information.
OIL PRESSURE LOW
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.
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 5-14for more information.
3-49

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, if equipped, will acknowledge the
message and clear it from the DIC display. If your
vehicle is not equipped with 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 5-26for more information.
SERVICE 4WD
If a problem occurs with the four-wheel-drive system, this
message will appear on the DIC. If this message
appears, stop as soon as possible and turn off the
vehicle. Restart the vehicle and check for the message
on the DIC display. If the message is still displayed or
appears again when you begin driving, the
four-wheel-drive system needs service. See your
GM dealer. Pressing any of the four DIC buttons, if
equipped, will acknowledge the message and clear it
from the DIC display. If your vehicle is not equipped with
the four DIC buttons, pressing the trip odometer reset
stem will acknowledge the message and clear it from the
DIC display.
SERVICE AIRBAG
If there is a problem with the airbag system, this message
will be displayed on the DIC. Have your GM dealer
inspect the system for problems. SeeAirbag Readiness
Light on page 3-29andAirbag System on page 1-48for
more information. Pressing any of the four DIC buttons, if
equipped, will acknowledge the message and clear it
from the DIC display. If your vehicle is not equipped with
the four DIC buttons, pressing the trip odometer reset
stem will acknowledge the message and clear it from the
DIC display.
3-50

TRANS HOT IDLE ENGINE
If the transmission uid in the vehicle gets hot, this
message will appear on the DIC and you will hear a
chime. The chime will stop when the transmission uid
temperature is less that 265°F (129°C). 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 when the uid temperature reaches a safe level.
SeeTransmission Temperature Gage on page 3-34.
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 transmission
temperature warning is displayed.
TRANSMISSION HOT
If the transmission uid temperature becomes high, this
message will appear on the DIC display.
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.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 transmission
temperature warning is displayed.
The following situations can cause the transmission to
operate at higher temperatures:
Towing a trailer
Hot outside air temperatures
Hauling a large or heavy load
Over-loading
Low transmission uid level
High transmission uid level
Restricted air ow to the radiator and the auxiliary
transmission oil cooler
A temporary solution to hotter transmission operating
temperatures may be to let the transmission cool down.
If the transmission is operated at higher temperatures
on a frequent basis, seeScheduled Maintenance
on page 6-4for the proper transmission maintenance
intervals.
3-53

Driving Downhill
When off-roading takes you downhill, you will want to
consider a number of things:
How steep is the downhill? Will I be able to maintain
vehicle control?
What is the surface like? Smooth? Rough?
Slippery? Hard-packed dirt? Gravel?
Are there hidden surface obstacles? Ruts? Logs?
Boulders?
What is at the bottom of the hill? Is there a hidden
creek bank or even a river bottom with large rocks?
If you decide you can go down a hill safely, then try to
keep your vehicle headed straight down, and use a
low gear. This way, engine drag can help your brakes
and they will not have to do all the work. Descend
slowly, keeping your vehicle under control at all times.
{CAUTION:
Heavy braking when going down a hill can
cause your brakes to overheat and fade. This
could cause loss of control and a serious
accident. Apply the brakes lightly when
descending a hill and use a low gear to keep
vehicle speed under control.
Q:Are there some things I should not do when
driving down a hill?
A:Yes! These are important because if you ignore
them you could lose control and have a serious
accident.
When driving downhill, avoid turns that take you
across the incline of the hill. A hill that is not too
steep to drive down may be too steep to drive
across. You could roll over if you do not drive
straight down.
Never go downhill with the transmission in
NEUTRAL (N). This is called “free-wheeling.” Your
brakes will have to do all the work and could
overheat and fade.
4-21