ecu GMC YUKON 2012 Service Manual

Black plate (60,1)GMC Yukon/Yukon XL Owner Manual - 2012
5-60 Instruments and Controls
7. Immediately release the buttonwhen the garage door moves.
The indicator light will blink
rapidly until programming is
complete.
8. Press and release the same button again. The garage door
should move, confirming that
programming is successful and
complete.
To program another Fixed Code
device such as an additional garage
door opener, a security device,
or home automation device, repeat
Steps 1-8, choosing a different
button in Step 6 than what was used
for the garage door opener.Universal Remote System
Operation
Press and hold the appropriate
button for at least half of a second.
The indicator light will come on
while the signal is being transmitted.
Reprogramming Universal
Home Remote Buttons
Any of the three buttons can be
reprogrammed by repeating the
instructions.
Erasing Universal Home
Remote Buttons
The programmed buttons should be
erased when the vehicle is sold or
the lease ends.
To erase either Rolling Code or
Fixed Code settings on the
Universal Home Remote device:
1. Press and hold the two outside buttons at the same time for
approximately 20 seconds, until
the indicator lights, located
directly above the buttons, begin
to blink rapidly.
2. Once the indicator lights begin to blink, release both buttons. The
codes from all buttons will be
erased.
For help or information on the
Universal Home Remote System,
call the customer assistance phone
number under Customer Assistance
Offices on page 13‑3.

Black plate (12,1)GMC Yukon/Yukon XL Owner Manual - 2012
7-12 Infotainment System
No CAT Info:No category
information is available at this time
on this channel. The system is
working properly.
No Information: No text or
informational messages are
available at this time on this
channel. The system is working
properly.
No Subscription Please Renew:
The XM subscription needs to be
reactivated. Contact XM at
www.xmradio.com or call
1-800-929-2100 in the U.S.
and www.xmradio.ca or call
1-877-438-9677 in Canada.
CAT Not Found: There are no
channels available for the selected
category. The system is working
properly.
XM Theftlocked: The XM receiver
in the vehicle could have previously
been in another vehicle. For security
purposes, XM receivers cannot be
swapped between vehicles. If this message is received after having
the vehicle serviced, check with
your dealer.
XM Radio ID:
If tuned to channel 0,
this message alternates with the XM
Radio eight‐digit radio ID label. This
label is needed to activate the
service.
Unknown: If this message is
received when tuned to channel 0,
there could be a receiver fault.
Consult with your dealer.
Check Antenna: If this message
does not clear within a short period
of time, the receiver or antenna
could have a fault. Consult with your
dealer.
Check XM Receivr: If this
message does not clear within a
short period of time, the receiver
could have a fault. Consult with your
dealer.
XM Not Available: If this message
does not clear within a short period
of time, the receiver could have a
fault. Consult with your dealer.Radio Reception
Frequency interference and static
can occur during normal radio
reception if items such as cell phone
chargers, vehicle convenience
accessories, and external electronic
devices are plugged into the
accessory power outlet. If there is
interference or static, unplug the
item from the accessory power
outlet.
AM
The range for most AM stations is
greater than for FM, especially at
night. The longer range can cause
station frequencies to interfere with
each other. For better radio
reception, most AM radio stations
boost the power levels during the
day, and then reduce these levels
during the night. Static can also
occur when things like storms and
power lines interfere with radio
reception. When this happens, try
reducing the treble on the radio.

Black plate (7,1)GMC Yukon/Yukon XL Owner Manual - 2012
Driving and Operating 9-7
Loading the Vehicle for
Off-Road Driving
{WARNING
.Unsecured cargo on the load
floor can be tossed about
when driving over rough
terrain. You or your
passengers can be struck by
flying objects. Secure the
cargo properly.
.Keep cargo in the cargo area
as far forward and as low as
possible. The heaviest things
should be on the floor,
forward of the rear axle.
.Heavy loads on the roof raise
the vehicle's center of gravity,
making it more likely to roll
over. You can be seriously or
fatally injured if the vehicle
rolls over. Put heavy loads
inside the cargo area, not on
the roof.For more information about loading
the vehicle, see Vehicle Load Limits
and Tires.
Environmental Concerns
.Always use established trails,
roads, and areas that have been
set aside for public off-road
recreational driving and obey all
posted regulations.
.Do not damage shrubs, flowers,
trees, or grasses or disturb
wildlife.
.Do not park over things that
burn. See Parking Over Things
that Burn..
Driving on Hills
Driving safely on hills requires good
judgment and an understanding of
what the vehicle can and cannot do.
{WARNING
Many hills are simply too steep
for any vehicle. Driving up hills
can cause the vehicle to stall.
Driving down hills can cause loss
of control. Driving across hills can
cause a rollover. You could be
injured or killed. Do not drive on
steep hills.
Before driving on a hill, assess
the steepness, traction, and
obstructions. If the terrain ahead
cannot be seen, get out of the
vehicle and walk the hill before
driving further.

Black plate (20,1)GMC Yukon/Yukon XL Owner Manual - 2012
9-20 Driving and Operating
And, if you do have a heavy
load, you should spread it out.
{WARNING
Do not load the vehicle any
heavier than the Gross
Vehicle Weight Rating
(GVWR), or either the
maximum front or rear Gross
Axle Weight Rating (GAWR).
This can cause systems to
break and change the way the
vehicle handles. This could
cause loss of control and a
crash. Overloading can also
shorten the life of the vehicle.
Notice: Overloading the
vehicle may cause damage.
Repairs would not be covered
by the vehicle warranty. Do
not overload the vehicle. The label will help you decide
how much cargo and installed
equipment your truck can carry.
Using heavier suspension
components to get added
durability might not change your
weight ratings. Ask your dealer
to help you load your vehicle the
right way.
If you put things inside your
vehicle
—like suitcases, tools,
packages, or anything
else —they go as fast as the
vehicle goes. If you have to stop
or turn quickly, or if there is a
crash, they will keep going.
{WARNING
Things you put inside the
vehicle can strike and injure
people in a sudden stop or
turn, or in a crash.
.Put things in the cargo
area of the vehicle. Try to
spread the weight evenly.
.Never stack heavier
things, like suitcases,
inside the vehicle so that
some of them are above
the tops of the seats.
.Do not leave an
unsecured child restraint
in the vehicle.
(Continued)

Black plate (21,1)GMC Yukon/Yukon XL Owner Manual - 2012
Driving and Operating 9-21
WARNING (Continued)
.When you carry something
inside the vehicle, secure
it whenever you can.
.Do not leave a seat folded
down unless you need to.
There is also important loading
information for off-road driving in
this manual. See “Loading Your
Vehicle for Off-Road Driving”
under Off-Road Driving on
page 9‑6.
Starting and
Operating
New Vehicle Break-In
Notice: The vehicle does not
need an elaborate break-in. But it
will perform better in the long run
if you follow these guidelines:
.Keep the vehicle speed at
88 km/h (55 mph) or less for
the first 805 km (500 miles).
.Do not drive at any one
constant speed, fast or
slow, for the first 805 km
(500 miles). Do not make
full-throttle starts. Avoid
downshifting to brake or
slow the vehicle.
.Avoid making hard stops for
the first 322 km (200 miles) or
so. During this time the new
brake linings are not yet
broken in. Hard stops with
new linings can mean
premature wear and earlier
replacement. Follow this
breaking-in guideline every
time you get new brake
linings.
.Do not tow a trailer during
break-in. See Trailer Towing
on page 9‑72 for the trailer
towing capabilities of the
vehicle and more
information.
Following break‐in, engine speed
and load can be gradually
increased.

Black plate (26,1)GMC Yukon/Yukon XL Owner Manual - 2012
9-26 Driving and Operating
Engine Heater
The engine coolant heater can
provide easier starting and better
fuel economy during engine
warm-up in cold weather conditions
at or below−18°C (0°F). Vehicles
with an engine heater should be
plugged in at least four hours before
starting. An internal thermostat in
the plug-end of the cord may exist
which will prevent engine coolant
heater operation at temperatures
above −18°C (0°F).
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
(Continued)
WARNING (Continued)
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.

Black plate (69,1)GMC Yukon/Yukon XL Owner Manual - 2012
Driving and Operating 9-69
WARNING (Continued)
To maximize safety when towing
a trailer:
.Have the exhaust system
inspected for leaks and make
necessary repairs before
starting a trip.
.Never drive with the liftgate,
trunk/hatch, or rear-most
window open.
.Fully open the air outlets on
or under the instrument
panel.
.Adjust the Climate Control
system to a setting that
brings in only outside air and
set the fan speed to the
highest setting. See Climate
Control System in the Index.
For more information about
Carbon Monoxide, see Engine
Exhaust on page 9‑30. Towing a trailer requires a certain
amount of experience. The
combination you are driving is
longer and not as responsive as the
vehicle itself. Get acquainted with
the handling and braking of the rig
before setting out for the open road.
Before starting, check all trailer
hitch parts and attachments, safety
chains, electrical connectors,
lamps, tires and mirrors. If the
trailer has electric brakes, start the
combination moving and then apply
the trailer brake controller by hand
to be sure the brakes work.
During the trip, check occasionally
to be sure that the load is secure
and the lamps and any trailer
brakes still work.
Following Distance
Stay at least twice as far behind the
vehicle ahead as you would when
driving the vehicle without a trailer.
This can help to avoid heavy
braking and sudden turns.
Passing
More passing distance is needed
when towing a trailer. The
combination will not accelerate as
quickly and is longer so it is
necessary to go much farther
beyond the passed vehicle before
returning to the lane.
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.

Black plate (87,1)GMC Yukon/Yukon XL Owner Manual - 2012
Driving and Operating 9-87
Some vehicles are built with a
special snow plow prep package,
called RPO VYU. If the vehicle has
this option, you can add a plow to it,
provided certain weights, such as
the weights on the vehicle's axles
and the Gross Vehicle Weight
(GVW), are not exceeded.
The plow the vehicle can carry
depends on many things, such as:
.The options the vehicle came
with, and the weight of those
options.
.The weight and number of
passengers intended to be
carried.
.The weight of items added to the
vehicle.
.The total weight of any
additional cargo intended to be
carried.Say, for example, you have a 318 kg
(700 lb) snow plow. The total weight
of all occupants and cargo inside
the cab should not exceed 135 kg
(300 lb). This means that you may
only be able to carry one passenger.
But, even this may be too much if
there is other equipment already
adding to the weight of the vehicle.
Here are some guidelines for safely
carrying a snow plow on the vehicle:
.Make sure the weight on the
front and rear axles does not
exceed the axle rating for each.
.For the front axle, if more cargo
or passengers must be carried,
appropriate counter ballast must
be installed rear of the rear axle.
Counter ballast must be properly
secured so it will not move
during driving.
.Follow the snow plow
manufacturer's
recommendations regarding
rear ballast. Rear ballast may be
required to ensure a proper front
and rear weight distribution ratio,
even though the actual weight at
the front axle may be less than
the front axle rating.
.The snow plow manufacturer or
installer can assist in
determining the amount of rear
ballast required, to help make
sure the snowplow/vehicle
combination does not exceed
the GVW rating, the front and
rear axle ratings, and the front
and rear weight distribution ratio.
.The total vehicle must not
exceed the GVW rating.

Black plate (21,1)GMC Yukon/Yukon XL Owner Manual - 2012
Vehicle Care 10-21
4. With the coolant surge tankpressure cap off, start the
engine and let it run until the
upper radiator hose can be felt
getting hot. Watch out for the
engine cooling fan.
By this time, the coolant level
inside the coolant surge tank
may be lower. If the level is
lower, add more of the proper
mixture to the coolant surge tank
until the level reaches the FULL
COLD mark. 5. Replace the pressure cap. Be
sure the pressure cap is
hand-tight and fully seated.
6. Verify coolant level after engine is shut off and the coolant is
cold. If necessary, repeat coolant
fill procedure Steps 1 through 6.
Notice: If the pressure cap is not
tightly installed, coolant loss and
possible engine damage may
occur. Be sure the cap is properly
and tightly secured.
Engine Overheating
The vehicle has several indicators
to warn of engine overheating.
There is a coolant temperature
gauge on your vehicle's instrument
panel. See Engine Coolant
Temperature Gauge on page 5‑16. In addition, ENGINE OVERHEATED
STOP ENGINE, ENGINE
OVERHEATED IDLE ENGINE, and
an ENGINE POWER IS REDUCED
message comes on in the Driver
Information Center (DIC) on the
instrument panel. See
Engine
Cooling System Messages on
page 5‑39 andEngine Power
Messages on page 5‑41.
If the decision is made not to lift the
hood when this warning appears,
but instead get service help right
away. See Roadside Assistance
Program on page 13‑5.
If the decision is made to lift the
hood, make sure the vehicle is
parked on a level surface.

Black plate (70,1)GMC Yukon/Yukon XL Owner Manual - 2012
10-70 Vehicle Care
Tire Chains
If your vehicle is a Hybrid, see the
Hybrid Supplement for more
information.
{WARNING
If the vehicle has P265/65R18 or
P275/55R20 size tires, do not use
tire chains. There is not enough
clearance. Tire chains used on a
vehicle without the proper amount
of clearance can cause damage
to the brakes, suspension,
or other vehicle parts. The area
damaged by the tire chains could
cause loss of control and a crash.(Continued)
WARNING (Continued)
Use another type of traction
device only if its manufacturer
recommends it for the vehicle's
tire size combination and
road conditions. Follow that
manufacturer's instructions. To
avoid vehicle damage, drive slow
and readjust or remove the
traction device if it is contacting
the vehicle. Do not spin the
wheels.
If traction devices are used, install
them on the rear tires. Notice:
If the vehicle has
P265/70R17 size tires, use tire
chains only where legal and only
when necessary. Use chains that
are the proper size for the tires.
Install them on the rear tires only.
Do not use chains on the front
tires.
Tighten them as tightly as
possible with the ends securely
fastened. Drive slowly and
follow the chain manufacturer's
instructions. If the chains contact
the vehicle, stop and retighten
them. If the contact continues,
slow down until it stops. Driving
too fast or spinning the wheels
with chains on will damage the
vehicle.