2009 GMC SIERRA 1500 light

Heavy-DutyTrailer Wiring Harness
Package
For vehicles equipped with heavy duty trailering, the
harness is connected to a bracket on the hitch platform.
The seven-wire harness contains the following trailer
circuits:
Yellow: Left Stop/Turn Signal
Dark Green: Right Stop/Turn Signal
Brown: Taillamps
White: Ground
Light Green: Back-up Lamps
Red: Battery Feed*
Dark Blue: Trailer Brake**The fuses for these two circuits are installed in the
underhood electrical center, but the wires are not
connected. They should be connected by your
dealer/retailer or a qualied service center. The fuse
and wire for the ITBC is factory installed and connected
if the vehicle is equipped with an ITBC. The fuse for
the battery feed is not required if the vehicle has
an auxiliary battery. If the vehicle does not have an
auxiliary battery, have your dealer/retailer or authorized
service center install the required fuse.
If charging a remote (non-vehicle) battery, press the
tow/haul mode button located at the end of the shift lever.
This will boost the vehicle system voltage and properly
charge the battery. If the trailer is too light for tow/haul
mode, turn on the headlamps as a second way to boost
the vehicle system and charge the battery.
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Camper/Fifth-Wheel Trailer Wiring Package
The seven-wire camper harness is located under the
front edge of the pickup box on the drivers side of
the vehicle, attached to the frame bracket. A connector
must be added to the wiring harness which connects
to the camper.
The harness contains the following camper/trailer
circuits:
Yellow: Left Stop/Turn Signal
Dark Green: Right Stop/Turn Signal
Brown: Taillamps
White: Ground
Light Green: Back-up Lamps
Red: Battery Feed
Dark Blue: Trailer BrakeIf the vehicle is equipped with the “Heavy-Duty
Trailering” option, please refer to “Heavy-Duty Trailer
Wiring Package” earlier in this section.
When the camper-wiring harness is ordered without the
heavy-duty trailering package, an eight-wire harness
with a seven-pin connector is located at the rear of the
vehicle and is tied to the vehicle’s frame.
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Electric Brake Control Wiring
Provisions
These wiring provisions are included with the vehicle as
part of the trailer wiring package. These provisions are for
an electric brake controller. The instrument panel
contains blunt cut wires behind the steering column for
the trailer brake controller. The harness contains the
following wires:
Dark Blue: Brake Signal to Trailer Connector
Red/Black: Battery
Light Blue/White: Brake Switch
White: Ground
It should be installed by your dealer/retailer or a qualied
service center.
If the vehicle is equipped with an ITBC, the blunt cuts
exist, but are not connected further in the harness. If an
aftermarket trailer brake controller is installed, the ITBC
must be disconnected. Do not power both ITBC and
aftermarket controllers to control the trailer brakes at the
same time.
Auxiliary Battery
The auxiliary battery provision can be used to supply
electrical power to additional equipment that may be
added, such as a slide-in camper. If the vehicle has this
provision, this relay will be located on the drivers side of
the vehicle, next to the underhood electrical center.Be sure to follow the proper installation instructions that
are included with any electrical equipment that is
installed.
Notice:Leaving electrical equipment on for
extended periods will drain the battery. Always turn
off electrical equipment when not in use and do not
use equipment that exceeds the maximum amperage
rating for the auxiliary battery provision.
Trailer Recommendations
Subtract the hitch loads from the Cargo Weight Rating
(CWR). CWR is the maximum weight of the load
the vehicle can carry. It does not include the weight of
the people inside, but you can gure about 150 lbs.
(68 kg) for each passenger. The total cargo load must
not be more than the vehicles CWR.
Weigh the vehicle with the trailer attached, so the
GVWR or GAWR are not exceeded. If using a
weight-distributing hitch, weigh the vehicle without the
spring bars in place.
The best performance is obtained by correctly spreading
out the weight of the load and choosing the correct
hitch and trailer brakes.
For more information seeTowing a Trailer on page 4-53.
4-84

Gasoline Octane
For all vehicles except those with the 6.2L V8 engine
(VIN Code 2), use regular unleaded gasoline with a
posted octane rating of 87 or higher. If the octane rating
is less than 87, you might notice an audible knocking
noise when you drive, commonly referred to as spark
knock. If this occurs, use a gasoline rated at 87 octane
or higher as soon as possible. If you are using gasoline
rated at 87 octane or higher and you hear heavy
knocking, the engine needs service.
If the vehicle has the 6.2L V8 engine (VIN Code 2),
use premium unleaded gasoline with a posted octane
rating of 91 or higher. You can also use regular unleaded
gasoline rated at 87 octane or higher, but the vehicle’s
acceleration could be slightly reduced, and you might
notice a slight audible knocking noise, commonly referred
to as spark knock. If the octane is less than 87, you might
notice a heavy knocking noise when you drive. If this
occurs, use a gasoline rated at 87 octane or higher as
soon as possible. Otherwise, you could damage the
engine. If you are using gasoline rated at 87 octane or
higher and you hear heavy knocking, the engine needs
service.
Gasoline Specications
At a minimum, gasoline should meet ASTM specication
D 4814 in the United States or CAN/CGSB-3.5 or 3.511 in
Canada. Some gasolines contain an octane-enhancing
additive called methylcyclopentadienyl manganese
tricarbonyl (MMT). We recommend against the use of
gasolines containing MMT. SeeAdditives on page 5-8
for additional information.
California Fuel
If the vehicle is certied to meet California Emissions
Standards, it is designed to operate on fuels that meet
California specications. See the underhood emission
control label. If this fuel is not available in states adopting
California emissions standards, the vehicle will operate
satisfactorily on fuels meeting federal specications, but
emission control system performance might be affected.
The malfunction indicator lamp could turn on and the
vehicle might fail a smog-check test. SeeMalfunction
Indicator Lamp on page 3-45. If this occurs, return to your
authorized dealer/retailer for diagnosis. If it is determined
that the condition is caused by the type of fuel used,
repairs might not be covered by the vehicle warranty.
5-7

The TIGHTEN GAS CAP message displays on the
Driver Information Center (DIC) if the fuel cap is
not properly installed. SeeDIC Warnings and
Messages on page 3-66for more information.
{CAUTION:
If a re starts while you are refueling, do not
remove the nozzle. Shut off the ow of fuel by
shutting off the pump or by notifying the station
attendant. Leave the area immediately.
Notice:If you need a new fuel cap, be sure to get
the right type. Your dealer/retailer can get one
for you. If you get the wrong type, it may not t
properly. This may cause the malfunction indicator
lamp to light and may damage the fuel tank and
emissions system. SeeMalfunction Indicator Lamp
on page 3-45.
Filling a Portable Fuel Container
{CAUTION:
Never ll a portable fuel container while it is in
the vehicle. Static electricity discharge from the
container can ignite the fuel vapor. You can be
badly burned and the vehicle damaged if this
occurs. To help avoid injury to you and others:
Dispense fuel only into approved containers.
Do not ll a container while it is inside a
vehicle, in a vehicle’s trunk, pickup bed,
or on any surface other than the ground.
Bring the ll nozzle in contact with the inside
of the ll opening before operating the nozzle.
Contact should be maintained until the lling
is complete.
Do not smoke while pumping fuel.
Do not use a cellular phone while
pumping fuel.
5-13

Engine Air Cleaner/Filter
If the vehicle has a diesel engine, see “Pickup Models”
under “Engine Air Cleaner/Filter” in the DURAMAX®
Diesel Supplement for the correct inspection and
replacement procedures.
SeeEngine Compartment Overview on page 5-16for
the location of the engine air cleaner/lter.
When to Inspect the Engine Air
Cleaner/Filter
Inspect the air cleaner/lter at the MaintenanceII
intervals and replace it at the rst oil change after
each 50,000 mile (80 000 km) interval. SeeScheduled
Maintenance (Gasoline Engine) on page 6-4for
more information. If driving on dusty/dirty conditions,
inspect the lter at each engine oil change.
How to Inspect the Engine Air
Cleaner/Filter
To inspect the air cleaner/lter, remove the engine
air cleaner/lter from the vehicle by following Steps 1
through 7. When the engine air cleaner/lter is removed,
lightly shake it to release loose dust and dirt. If the engine
air cleaner/lter remains caked with dirt, a new lter is
required.
Replacing the Engine Air Cleaner/Filter
1. Locate the air cleaner/lter assembly. SeeEngine
Compartment Overview on page 5-16.
2. Loosen the four screws on the cover of the housing
and lift up the cover.
5-22

Brake Wear
This vehicle has front disc brakes and could have rear
drum brakes or rear disc brakes.
Disc brake pads have built-in wear indicators that make
a high-pitched warning sound when the brake pads are
worn and new pads are needed. The sound can come
and go or be heard all the time the vehicle is moving,
except when applying the brake pedal rmly.
{CAUTION:
The brake wear warning sound means that soon
the brakes will not work well. That could lead to an
accident. When the brake wear warning sound is
heard, have the vehicle serviced.
Notice:Continuing to drive with worn-out brake
pads could result in costly brake repair.Some driving conditions or climates can cause a brake
squeal when the brakes are rst applied or lightly applied.
This does not mean something is wrong with the brakes.
Properly torqued wheel nuts are necessary to help
prevent brake pulsation. When tires are rotated, inspect
brake pads for wear and evenly tighten wheel nuts
in the proper sequence to torque specications
inCapacities and Specifications on page 5-131.
If the vehicle has rear drum brakes, they do not have
wear indicators, but if a rear brake rubbing noise is heard,
have the rear brake linings inspected immediately. Rear
brake drums should be removed and inspected each time
the tires are removed for rotation or changing. Drum
brakes have an inspection hole to inspect lining wear
during scheduled maintenance. When the front brake
pads are replaced, have the rear brakes inspected, too.
Brake linings should always be replaced as complete
axle sets.
5-44

Notice:Ignoring these steps could result in costly
damage to the vehicle that would not be covered
by the warranty.
Trying to start the vehicle by pushing or pulling it
will not work, and it could damage the vehicle.
1. Check the other vehicle. It must have a 12-volt
battery with a negative ground system.
Notice:If the other vehicle’s system is not a 12-volt
system with a negative ground, both vehicles can
be damaged. Only use vehicles with 12-volt systems
with negative grounds to jump start your vehicle.
2. If you have a vehicle with a diesel engine with two
batteries, you should know before you begin that,
especially in cold weather, you may not be able
to get enough power from a single battery in another
vehicle to start your diesel engine. If your vehicle
has more than one battery, use the battery that
is closer to the starter -- this will reduce electrical
resistance. This is located on the passenger side,
in the rear of the engine compartment.3. Get the vehicles close enough so the jumper cables
can reach, but be sure the vehicles are not touching
each other. If they are, it could cause an unwanted
ground connection. You would not be able to
start your vehicle, and the bad grounding could
damage the electrical systems.
To avoid the possibility of the vehicles rolling,
set the parking brake rmly on both vehicles involved
in the jump start procedure. Put the automatic
transmission in P (Park) or a manual transmission
in Neutral before setting the parking brake. If you
have a four-wheel-drive vehicle, be sure the transfer
case is in a drive gear, not in Neutral.
Notice:If you leave the radio or other accessories
on during the jump starting procedure, they could
be damaged. The repairs would not be covered by
the warranty. Always turn off the radio and other
accessories when jump starting the vehicle.
4. Turn off the ignition on both vehicles. Unplug
unnecessary accessories plugged into the cigarette
lighter or the accessory power outlets. Turn off
the radio and all the lamps that are not needed.
This will avoid sparks and help save both batteries.
And it could save the radio!
5-47