engine overheat GMC YUKON 2010 Owner's Manual

Starting Procedure
1. With your foot off the accelerator pedal, turn theignition key to START. When the engine starts, let
go of the key. The idle speed will go down as the
engine gets warm. 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 for many seconds, 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, do the
same thing. 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. If you do
not, the engine might not perform properly.
Any resulting damage would not be covered
by the vehicle warranty.
3-30

To Use the Engine Coolant Heater
1. Turn off the engine.
2. Open the hood and unwrap the electrical cord.The cord is secured to the Engine Compartment
Fuse Block with a clip. Carefully remove the wire
tie which secures the electrical cord. Do not cut the
electrical cord.
3. Plug the cord into a normal, grounded 110-volt AC 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 in the area
where you will be parking the vehicle for the best advice
on this.
3-32

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.
If you have four-wheel drive and the transfer case
is in N (Neutral), the vehicle will be free to roll,
even if the shift lever is in P (Park). So be sure
the transfer case is in a drive gear—not in
N (Neutral).
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 unless you
have to.
If you have to leave the vehicle with the engine running,
be sure your vehicle is in P (Park) and the parking
brake is firmly set before you leave it. After you move the shift lever 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).
Torque Lock
If you are parking on a hill and you do not shift your
transmission into P (Park) properly, the weight of the
vehicle may put too much force on the parking pawl
in the transmission. You may find it difficult to pull the
shift lever out of P (Park). This is called torque lock.
To prevent torque lock, set the parking brake and then
shift into P (Park) properly before you leave the driver
seat. To find out how, see
Shifting Into Park
on
page 3‑49.
When you are ready to drive, move the shift lever out of
P (Park) 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,
then you will be able to pull the shift lever out of
P (Park).
3-50

StabiliTrak®Indicator Light
For vehicles with the
StabiliTrak®system, this
light comes on briefly
while starting the engine.
If it does not, have the vehicle serviced by your dealer.
If the system is working normally the indicator light then
goes off.
If the light comes on and stays on while driving, there
could be a problem with the StabiliTrak
®system and the
vehicle might need service. When this warning light is
on, the StabiliTrak
®system is off and does not limit
wheel spin.
The light flashes if the system is active and is working
to assist the driver with directional control of the vehicle
in difficult driving conditions.
See StabiliTrak
®Systemon page 5‑6for more
information.
Engine Coolant Temperature Gauge
United StatesCanada
This gauge shows the engine coolant temperature.
It also provides an indicator of how hard the vehicle is
working. During a majority of the operation, the gauge
reads 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
gauge reaches the 260°F (125°C) mark, it indicates that
the cooling system is working beyond its capacity.
See Engine Overheating on page 6‑36.
If the vehicle is a Two-mode Hybrid, see the Two-mode
Hybrid manual for more information.
4-38

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 6‑36for
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 Gauge on page 4‑38.
See Overheated Engine Protection Operating Mode
on
page 6‑39for 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 6‑36for
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 6‑36for 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 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
Gauge
on page 4‑46and Fuelon page 6‑6for
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.
4-63

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. SeeBrake System Warning
Light on page 4‑36.
.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.
.The message also displays if the vehicle is shifted
into 4LO (Two Speed Transfer Case Only).
The message turns off as soon as the conditions that
caused the message to be displayed are no longer
present.
TIGHTEN GAS CAP
This message may display along with the check engine
light on the instrument panel cluster if the vehicle's fuel
cap is not tightened properly. See Malfunction Indicator
Lamp
on page 4‑39. Reinstall the fuel cap fully.
See Filling the Tankon page 6‑11. The diagnostic
system can determine if the fuel cap has been left off or
improperly installed. A loose or missing fuel cap allows
fuel to evaporate into the atmosphere. A few driving
trips with the cap properly installed should turn this light
and message off.
TIRE LEARNING ACTIVE
On vehicles with the Tire Pressure Monitor System
(TPMS), this message displays when the TPMS is
re-learning the tire positions on your vehicle. The tire
positions must be re-learned after rotating the tires or
after replacing a tire or sensor. See Tire Inspection and
Rotation
on page 6‑78, Tire Pressure Monitor Systemon page 6‑73, and Inflation - Tire Pressureon
page 6‑72for more information.
4-69

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 6‑16for the location of the windshield washer
fluid reservoir. Also, see Windshield Washer Fluidon
page 6‑41for more information.
4-71

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.
5-20

WARNING: (Continued)
You cannot see it or smell it, so you might not
know it is in your vehicle. Clear away snow from
around the base of your vehicle, especially any
that is blocking the exhaust.
Run the engine for short periods only as needed to
keep warm, but be careful.
To save fuel, run the engine for only short periods as
needed to warm the vehicle and then shut the engine
off and close the window most of the way to save heat.
Repeat this until help arrives but only when you feel
really uncomfortable from the cold. Moving about to
keep warm also helps.
If it takes some time for help to arrive, now and then
when you run the engine, push the accelerator pedal
slightly so the engine runs faster than the idle speed.
This keeps the battery charged to restart the vehicle
and to signal for help with the headlamps. Do this as
little as possible to save fuel.
If Your Vehicle is Stuck in Sand,
Mud, Ice, or Snow
Slowly and cautiously spin the wheels to free the
vehicle when stuck in sand, mud, ice, or snow.
See Rocking Your Vehicle to Get It Out on page 5‑30.
If the vehicle has a traction system, it can often help
to free a stuck vehicle. Refer to the vehicle's traction
system in the Index. If stuck too severely for the traction
system to free the vehicle, turn the traction system off
and use the rocking method.
{WARNING:
If the vehicle's tires spin at high speed, they can
explode, and you or others could be injured.
The vehicle can overheat, causing an engine
compartment fire or other damage. Spin the
wheels as little as possible and avoid going above
55 km/h (35 mph) as shown on the speedometer.
For information about using tire chains on the vehicle,
see Tire Chains on page 6‑86.
5-29

Backing Up
Hold the bottom of the steering wheel with one hand.
Then, to move the trailer to the left, move that hand to
the left. To move the trailer to the right, move your hand
to the right. Always back up slowly and, if possible,
have someone guide you.
Making Turns
Notice:Making very sharp turns while trailering
could cause the trailer to come in contact with the
vehicle. The vehicle could be damaged. Avoid
making very sharp turns while trailering.
When turning with a trailer, make wider turns than
normal. Do this so the trailer will not strike soft
shoulders, curbs, road signs, trees or other objects.
Avoid jerky or sudden maneuvers. Signal well in
advance.
If the trailer turn signal bulbs burn out, the arrows on the
instrument panel will still flash for turns. It is important to
check occasionally to be sure the trailer bulbs are still
working.
Driving On Grades
Reduce speed and shift to a lower gear beforestarting
down a long or steep downgrade. If the transmission
is not shifted down, the brakes might get hot and no
longer work well.
Vehicles can tow in D (Drive). Shift the transmission to
a lower gear if the transmission shifts too often under
heavy loads and/or hilly conditions.
The tow/haul mode may be used if the transmission
shifts too often. See Tow/Haul Mode on page 3‑39.
When towing at high altitude on steep uphill grades,
consider the following: Engine coolant will boil at a
lower temperature than at normal altitudes. If the engine
is turned off immediately after towing at high altitude on
steep uphill grades, the vehicle may show signs similar
to engine overheating. To avoid this, let the engine run
while parked, preferably on level ground, with the
automatic transmission in P (Park) for a few minutes
before turning the engine off. If the overheat warning
comes on, see Engine Overheating on page 6‑36.
5-65