2010 GMC YUKON DENALI engine overheat

Starting Procedure
1. With your foot off the accelerator pedal, turn theignition to START. When the engine starts,
let go of the key. The idle speed will slow down
as the engine warms. Do not race the engine
immediately after starting it. Operate the engine
and transmission gently to allow the oil to warm up
and lubricate all moving parts.
The vehicle has a Computer-Controlled Cranking
System. This feature assists in starting the engine
and protects components. If the ignition key is
turned to the START position, and then released
when the engine begins cranking, the engine will
continue cranking for a few seconds or until the
vehicle starts. If the engine does not start and the
key is held in START, cranking will be stopped
after 15 seconds to prevent cranking motor
damage. To prevent gear damage, this system also
prevents cranking if the engine is already running.
Engine cranking can be stopped by turning the
ignition switch to the ACC/ACCESSORY or
LOCK/OFF position.
Notice: Cranking the engine for long periods of
time, by returning the key to the START position
immediately after cranking has ended, can overheat
and damage the cranking motor, and drain the
battery. Wait at least 15 seconds between each try,
to let the cranking motor cool down. 2. If the engine does not start after 5‐10 seconds,
especially in very cold weather (below 0°F or
−18°C), it could be flooded with too much gasoline.
Try pushing the accelerator pedal all the way to the
floor and holding it there as you hold the key in
START for up to a maximum of 15 seconds. Wait at
least 15 seconds between each try, to allow the
cranking motor to cool down. When the engine
starts, let go of the key and accelerator. If the
vehicle starts briefly but then stops again, repeat
these steps. This clears the extra gasoline from the
engine. Do not race the engine immediately after
starting it. Operate the engine and transmission
gently until the oil warms up and lubricates all
moving parts.
Notice: The engine is designed to work with the
electronics in the vehicle. If you add electrical
parts or accessories, you could change the way
the engine operates. Before adding electrical
equipment, check with your dealer/retailer. If you
do not, the engine might not perform properly.
Any resulting damage would not be covered by the
vehicle warranty.
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3. Plug the cord into a normal, grounded 110-voltAC outlet.
{WARNING:
Plugging the cord into an ungrounded outlet could
cause an electrical shock. Also, the wrong kind of
extension cord could overheat and cause a fire.
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.
The length of time the heater should remain plugged in
depends on several factors. Ask a dealer/retailer in the
area where you will be parking the vehicle for the best
advice on this.
Active Fuel Management™
Vehicles with V8 engines may have Active Fuel
Management™. This system allows the engine to
operate on either all or half of its cylinders, depending
on the driving conditions.
When less power is required, such as cruising at a
constant vehicle speed, the system will operate in the
half cylinder mode, allowing the vehicle to achieve
better fuel economy. When greater power demands are
required, such as accelerating from a stop, passing,
or merging onto a freeway, the system will maintain
full-cylinder operation.
If the vehicle has an Active Fuel Management™
indicator, see DIC Operation and Displays (Using DIC
Buttons)
on page 4‑43or DIC Operation and Displays
(Using Trip Odometer Reset Stem)on page 4‑50for
more information on using this display .
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Shifting Into Park
{WARNING:
It can be dangerous to get out of the vehicle if the
shift lever is not fully in P (Park) with the parking
brake firmly set. The vehicle can roll. If you have
left the engine running, the vehicle can move
suddenly. You or others could be injured. To be
sure the 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 5‑42
.
1. Hold the brake pedal down, then set the parking brake.
2. Move the shift lever into the P (Park) position by pulling the shift lever toward you and moving it up
as far as it will go.
3. Turn the ignition key to LOCK/OFF.
4. Remove the key and take it with you. If you can leave the vehicle with the ignition key in your hand,
the vehicle is in P (Park).
Leaving the Vehicle With the Engine
Running
{WARNING:
It can be dangerous to leave the vehicle with the
engine running. The vehicle could move suddenly
if the shift lever is not fully in P (Park) with the
parking brake firmly set. And, if you leave the
vehicle with the engine running, it could overheat
and even catch fire. You or others could be
injured. Do not leave the vehicle with the engine
running.
If you have to leave the vehicle with the engine running,
be sure the vehicle is in P (Park) and the parking brake
is firmly set. After the shift lever is moved into P (Park),
hold the regular brake pedal down. Then, see if you can
move the shift lever away from P (Park) without first
pulling it toward you. If you can, it means that the shift
lever was not fully locked into P (Park).
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Engine Coolant Temperature Gage
United StatesCanada
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
fluctuate 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.
See Engine Overheating on page 6‑32.
Tire Pressure Light
For vehicles with a tire
pressure monitoring
system, this light comes
on briefly when the engine
is started. It provides
information about tire
pressures and the Tire
Pressure Monitoring
System.
When the Light is On Steady
This indicates that one or more of the tires is
significantly underinflated.
A tire pressure message in the Driver Information
Center (DIC), can accompany the light. See Driver
Information Center (DIC)
on page 4‑42for more
information. Stop and check the tires as soon as it is
safe to do so. If underinflated, inflate to the proper
pressure. See Inflation - Tire Pressure
on page 6‑64for more information.
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ENGINE OVERHEATED IDLE ENGINE
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. See Engine Overheating
on page 6‑32for
more information.
This message displays when the engine coolant
temperature is too hot. Stop and allow the vehicle to
idle until it cools down. See Engine Coolant
Temperature Gage on page 4‑34.
See Overheated Engine Protection Operating Mode
on
page 6‑35for information on driving to a safe place in
an emergency.
ENGINE OVERHEATED STOP ENGINE
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. See Engine Overheating
on page 6‑32for
more information.
This message displays and a chime sounds if the
engine cooling system reaches unsafe temperatures for
operation. Stop and turn off the vehicle as soon as it is
safe to do so to avoid severe damage. This message
clears when the engine has cooled to a safe operating
temperature.
ENGINE POWER IS REDUCED
This message displays and a chime sounds when the
cooling system temperature gets too hot and the engine
further enters the engine coolant protection mode. See
Engine Overheating
on page 6‑32for further
information.
This message also displays when the vehicle's engine
power is reduced. Reduced engine power can affect the
vehicle's ability to accelerate. If this message is on, but
there is no reduction in performance, proceed to your
destination. The performance may be reduced the next
time the vehicle is driven. The vehicle may be driven at
a reduced speed while this message is on, but
acceleration and speed may be reduced. Anytime this
message stays on, the vehicle should be taken to your
dealer/retailer for service as soon as possible.
FUEL LEVEL LOW
This message displays and a chime sounds if the fuel
level is low. Refuel as soon as possible. See Fuel Gage
on page 4‑41andFuelon page 6‑5for more
information.
HOOD OPEN
This message displays and a chime sounds if the hood
is not fully closed. Stop and turn off the vehicle, check
the hood for obstructions, and close the hood again.
Check to see if the message still appears on the DIC.
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SIDE BLIND ZONE SYSTEM
UNAVAILABLE
If your vehicle has the Side Blind Zone Alert (SBZA)
system, this message displays when the SBZA system
is disabled because the sensor is blocked and cannot
detect vehicles in your blind zone. The sensor may be
blocked by mud, dirt, snow, ice, or slush. This message
may also display during heavy rain or due to road spray.
It may also come on when driving in isolated areas
with no guardrails, trees, or road signs and light traffic.
Your vehicle does not need service. For cleaning
instructions, seeWashing Your Vehicle
on page 6‑102.
See Side Blind Zone Alert (SBZA)on page 3‑47for
more information.
STABILITRAK OFF
If your vehicle has StabiliTrak, this message displays
when you turn off StabiliTrak, or when the stability
control has been automatically disabled. To limit
wheel spin and realize the full benefits of the stability
enhancement system, you should normally leave
StabiliTrak on. However, you should turn StabiliTrak off
if your vehicle gets stuck in sand, mud, ice, or snow and
you want to rock your vehicle to attempt to free it, or if you are driving in extreme off-road conditions and
require more wheel spin. See
If Your Vehicle is Stuck in
Sand, Mud, Ice, or Snow
on page 5‑29. To turn the
StabiliTrak system on or off, see StabiliTrak®Systemon page 5‑6.
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 also displays if the brake system
warning light is on. See Brake System Warning
Light on page 4‑32.
.The message could display if the stability system
takes longer than usual to complete its diagnostic
checks due to driving conditions.
.The message displays if an engine or vehicle
related problem has been detected and the vehicle
needs service. See your dealer/retailer.
The message turns off as soon as the conditions that
caused the message to be displayed are no longer
present.
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TRAILER CONNECTED
On vehicles with the Integrated Trailer Brake
Control (ITBC) system, this message displays briefly
when a trailer with electric brakes is first connected to
the vehicle.
This message clears itself after several seconds. This
message also clears if you acknowledge it. After this
message clears, the TRAILER GAIN/OUTPUT display
appears in the DIC.
See“TRAILER GAIN/OUTPUT” underDIC Operation
and Displays (Using DIC Buttons)
on page 4‑43or DIC
Operation and Displays (Using Trip Odometer Reset
Stem)
on page 4‑50and “Integrated Trailer Brake
Control System” underTowing a Traileron page 5‑42for more information.
TRANSMISSION HOT IDLE ENGINE
Notice: If you drive your vehicle while the
transmission fluid 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 fluid or while the transmission
temperature warning is displayed. This message displays along with a sound if the
transmission fluid in the vehicle gets hot. Driving with
the transmission fluid temperature high can cause
damage to the vehicle. Stop the vehicle and let it idle to
allow the transmission to cool. This message clears and
the chime stops when the fluid temperature reaches a
safe level.
TURN SIGNAL ON
This message displays and a chime sounds if a turn
signal is left on for 3/4 of a mile (1.2 km). Move the turn
signal/multifunction lever to the off position.
WASHER FLUID LOW ADD FLUID
This message displays when the windshield washer
fluid is low. Fill the windshield washer fluid reservoir as
soon as possible. See
Engine Compartment Overview
on page 6‑14for the location of the windshield washer
fluid reservoir. Also, see Windshield Washer Fluidon
page 6‑37for more information.
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Driving Downhill
When off-roading takes you downhill, consider:
.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, try to keep
the vehicle headed straight down. Use a low gear so
engine drag can help the brakes so they do not have to
do all the work. Descend slowly, keeping the vehicle
under control at all times.
{WARNING:
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. Things not to do when driving down a hill:
.When driving downhill, avoid turns that take you
across the incline of the hill. A hill that is not too
steep to drive down might be too steep to drive
across. The vehicle could roll over.
.Never go downhill with the transmission in
N (Neutral), called free-wheeling. The brakes will
have to do all the work and could overheat
and fade.
Vehicles are much more likely to stall when going uphill,
but if it happens when going downhill: 1. Stop the vehicle by applying the regular brakes and apply the parking brake.
2. Shift to P (Park) and, while still braking, restart the engine.
3. Shift back to a low gear, release the parking brake, and drive straight down.
4. If the engine will not start, get out and get help.
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