2009 GMC YUKON fuel cap

This light comes on during a malfunction in one of
two ways:
Light Flashing:A misre condition has been detected.
A misre increases vehicle emissions and could
damage the emission control system on the vehicle.
Diagnosis and service might be required.
To prevent more serious damage to the vehicle:
Reduce vehicle speed.
Avoid hard accelerations.
Avoid steep uphill grades.
If towing a trailer, reduce the amount of cargo being
hauled as soon as it is possible.
If the light continues to ash, when it is safe to do so, stop
the vehicle. Find a safe place to park the vehicle. Turn the
key off, wait at least 10 seconds, and restart the engine.
If the light is still ashing, follow the previous steps and
see your dealer/retailer for service as soon as possible.
Light On Steady:An emission control system
malfunction has been detected on the vehicle. Diagnosis
and service might be required.An emission system malfunction might be corrected by
doing the following:
Make sure the fuel cap is fully installed. SeeFilling
the Tank on page 5-9. 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 the light off.
If the vehicle has been driven through a deep puddle
of water, the vehicle’s electrical system might be wet.
The condition is usually corrected when the electrical
system dries out. A few driving trips should turn the
light off.
Make sure to fuel the vehicle with quality fuel. Poor
fuel quality causes the engine not to run as efficiently
as designed and can cause: stalling after start-up,
stalling when the vehicle is changed into gear,
misring, hesitation on acceleration, or stumbling on
acceleration. These conditions might go away once
the engine is warmed up.
If one or more of these conditions occurs, change the
fuel brand used. It will require at least one full tank of
the proper fuel to turn the light off.
SeeGasoline Octane on page 5-5.
3-45

Fuel Gage
The fuel gage, when the ignition is on, shows how much
fuel the vehicle has left in the tank.
An arrow on the fuel gage indicates the side of the
vehicle the fuel door is on.
The gage rst indicates empty before the vehicle is out of
fuel, and the vehicle’s fuel tank should be lled soon.When the fuel tank is low, the FUEL LEVEL LOW
message appears in the Driver Information Center (DIC).
SeeDIC Warnings and Messages on page 3-64for
more information.
Here are some situations owners may experience with
the fuel gage. None of these indicate a problem
with the fuel gage.
At the gas station, the fuel pump shuts off before
the gage reads full.
It takes a little more or less fuel to ll up than the
fuel gage indicated. For example, the gage may
have indicated the tank was half full, but it actually
took a little more or less than half the tank’s
capacity to ll the tank.
The gage goes back to empty when the ignition is
turned off.
For vehicles with a Two-mode Hybrid, see the
Two-mode Hybrid manual for more information. United States
Canada
3-50

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 3-40.
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 also displays if the vehicle is shifted
into 4LO.
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. SeeMalfunction
Indicator Lamp on page 3-44. Reinstall the fuel cap fully.
SeeFilling the Tank on page 5-9. 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. SeeTire Inspection
and Rotation on page 5-78,Tire Pressure Monitor
System on page 5-72, andInflation - Tire Pressure on
page 5-70for more information.
3-72

Certication/Tire Label
A vehicle specic Certication/Tire label is found on
the rear edge of the driver’s door. The label shows
the size of your vehicle’s original tires and the
ination pressures needed to obtain the gross
weight capacity of your vehicle. This is called Gross
Vehicle Weight Rating (GVWR). The GVWR
includes the weight of the vehicle, all occupants,
fuel, and cargo.
The Certication/Tire label also tells you the
maximum weights for the front and rear axles,
called Gross Axle Weight Rating (GAWR).To nd out the actual loads on your front and rear
axles, you need to go to a weigh station and
weigh your vehicle. Your dealer can help you with
this. Be sure to spread out your load equally on
both sides of the centerline.
Never exceed the GVWR for your vehicle, or the
GAWR for either the front or rear axle.
The Certication/Tire label also contains
information about your Front Axle Reserve
Capacity.
And, if you do have a heavy load, you should
spread it out.
{CAUTION:
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). If you do, parts on
the vehicle can break, and it can change the
way your vehicle handles. These could cause
you to lose control and crash. Also,
overloading can shorten the life of the
vehicle.
4-38

Here are some guidelines for safely carrying a snow
plow on your 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
you in determining the amount of rear ballast
required, to help make sure your 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.Front axle reserve capacity is the difference between
your front Gross Axle Weight Rating (GAWR) and
the front axle weight of your vehicle with full fuel and
passengers. Basically, it is the amount of weight you can
add to your front axle before reaching your front GAWR.
The front axle reserve capacity for your vehicle can be
found in the lower right corner of the Certication/Tire
label, as shown.
United States
Canada
4-41

{CAUTION:
On some vehicles that have certain front mounted
equipment, such as a snow plow, it may be
possible to load the front axle to the front gross
axle weight rating (GAWR) but not have enough
weight on the rear axle to have proper braking
performance. If your brakes can not work properly,
you could have a crash. To help your brakes work
properly when a snow plow is installed, always
follow the snow plow manufacturer or installer’s
recommendation for rear ballast to ensure a
proper front and rear weight distribution ratio, even
though the actual front weight may be less than
the front GAWR, and the total vehicle weight is
less than the gross vehicle weight rating (GVWR).
Maintaining a proper front and rear weight
distribution ratio is necessary to provide proper
braking performance.Total vehicle reserve capacity is the difference between
your GVWR and the weight of your vehicle with full
fuel and passengers. It is the amount of weight you can
add to your vehicle before reaching your GVWR.
Keep in mind that reserve capacity numbers are
intended as a guide when selecting the amount of
equipment or cargo your vehicle can carry. If you are
unsure of your vehicle’s front, rear, or total weight, go to
a weigh station and weigh your vehicle. Your
dealer/retailer can also help you with this.
The total vehicle reserve capacity for your vehicle can
be found in the lower right corner of the Certication/Tire
label as shown previously.
See your dealer/retailer for additional advice and
information about using a snow plow on your vehicle.
Also, seeLoading the Vehicle on page 4-33.
Emergency Roof Lamp Provisions
Vehicles with the RPO VYU snow plow prep package
also have an emergency roof lamp provision package,
RPO TRW. Wiring for the emergency roof lamp is
provided above the overhead console. SeeAuxiliary
Roof Mounted Lamp on page 3-18for switch location.
4-43

Towing a Trailer
Do not tow a trailer during break-in. SeeNew Vehicle
Break-In on page 2-24for more information.
{CAUTION:
The driver can lose control when pulling a trailer if
the correct equipment is not used or the vehicle is
not driven properly. For example, if the trailer is
too heavy, the brakes may not work well — or
even at all. The driver and passengers could be
seriously injured. The vehicle may also be
damaged; the resulting repairs would not be
covered by the vehicle warranty. Pull a trailer only
if all the steps in this section have been followed.
Ask your dealer/retailer for advice and information
about towing a trailer with the vehicle.Notice:Pulling a trailer improperly can damage the
vehicle and result in costly repairs not covered
by the vehicle warranty. To pull a trailer correctly,
follow the advice in this section and see your
dealer/retailer for important information about
towing a trailer with the vehicle.
To identify the trailering capacity of the vehicle, read the
information in “Weight of the Trailer” that appears
later in this section.
Trailering is different than just driving the vehicle by itself.
Trailering means changes in handling, acceleration,
braking, durability and fuel economy. Successful, safe
trailering takes correct equipment, and it has to be used
properly.
The following information has many time-tested,
important trailering tips and safety rules. Many of these
are important for your safety and that of your passengers.
So please read this section carefully before pulling a
trailer.
4-52

Filling the Tank
{CAUTION:
Fuel vapor burns violently and a fuel re can
cause bad injuries. To help avoid injuries to you
and others, read and follow all the instructions on
the pump island. Turn off the engine when you are
refueling. Do not smoke if you are near fuel or
refueling the vehicle. Do not use cellular phones.
Keep sparks, ames, and smoking materials away
from fuel. Do not leave the fuel pump unattended
when refueling the vehicle. This is against the law
in some places. Do not re-enter the vehicle while
pumping fuel. Keep children away from the fuel
pump; never let children pump fuel.
The tethered fuel cap is located behind a hinged fuel
door on the driver side of the vehicle. If the vehicle has
E85 fuel capability, the fuel cap will be yellow and
state that E85 or gasoline can be used. SeeFuel E85
(85% Ethanol) on page 5-7.
5-9