2006 GMC SIERRA wiring

Headlamps
The control on the driver’s side of your instrument panel
operates the headlamps.
Turn the control clockwise to operate the lamps.
The headlamp control has four positions:
9(Off):Turning the control to this position turns off
the Daytime Running Lamps (DRL) and the automatic
headlamps.
AUTO (Automatic):Turning the control to this position
puts the system into automatic headlamp mode.
;(Parking Lamps):Turning the control to this
position turns on the parking lamps, together with
the following:
Sidemarker Lamps
Taillamps
License Plate Lamps
Instrument Panel Lights
Roof Marker Lamps (If Equipped)
5(Headlamps):Turning the control to this position
turns on the headlamps, together with the previously
listed lamps and lights.
You can switch your headlamps from high to low-beam
by pushing the turn signal/high-beam lever towards the
instrument panel.
A circuit breaker protects your headlamps. If you have an
electrical overload, your headlamps will icker on and off.
Have your headlamp wiring checked right away if this
happens.
Headlamps on Reminder
A reminder chime will sound when your headlamps or
parking lamps are manually turned on and your ignition is
off, in LOCK, ACCESSORY, or a door is open. To disable
the chime, turn the light off then back on.
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Auxiliary Roof Mounted Lamp
If your vehicle has this feature, this button includes
wiring provisions for a dealer or a qualied service
center to install an auxiliary roof lamp.
This button is located
on the center of the
instrument panel near
the climate controls.
When the wiring is connected to an auxiliary roof
mounted lamp, pressing the button will activate the lamp
and illuminate an indicator light near the button. Pressing
the button again will turn off the roof mounted lamp.
If your vehicle has this button, your vehicle may have the
snow plow prep package. For further information see
Adding a Snow Plow or Similar Equipment on page 4-54.
Instrument Panel Brightness
D(Instrument Panel Brightness):This feature
controls the brightness of the instrument panel lights.
The thumbwheel for this feature is located next to
the headlamp control.
Turn the thumbwheel up to adjust the instrument panel
lights. Turn the thumbwheel up to return the radio display
to full brightness when the headlamps or parking lamps
are on. To turn on the dome lamps, turn the thumbwheel
all the way up.
Dome Lamps
The dome lamps will come on when you open a door.
You can also turn the dome lamps on by turning the
thumbwheel, located next to the exterior lamps control,
all the way up. In this position, the dome lamps will
remain on whether a door is opened or closed.
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Airbag Readiness Light
There is an airbag readiness light on the instrument panel
cluster, which shows the airbag symbol. The system
checks the airbag’s electrical system for malfunctions.
The light tells you if there is an electrical problem. The
system check includes the airbag sensors, the airbag
modules, the passenger sensing system (if equipped),
the wiring and the crash sensing and diagnostic module.
For more information on the airbag system, seeAirbag
System on page 1-70.
This light will come on
when you start your
vehicle, and it will ash
for a few seconds. This
means the system is ready.
If the airbag readiness light stays on after you start the
vehicle or comes on when you are driving, your airbag
system may not work properly. Have your vehicle
serviced right away.
Airbag Off Light
If your vehicle has an airbag off switch, it also has an
airbag off light. SeeAirbag Off Switch on page 1-78for
more on this, including important safety information.
United StatesCanada
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Q:What is total vehicle reserve capacity?
A:This is the difference between your GVWR and the
weight of your truck 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 truck 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 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 for additional advice and information
about using a snow plow on your vehicle. Also, see
Loading Your Vehicle on page 4-48.
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 in the B-pillar as shown. SeeAuxiliary Roof
Mounted Lamp on page 3-18for switch location.
A. Body Side Inner Panel
B. Emergency Roof Lamp Harness
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When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the pedal down
while you:
Start your engine
Shift into a gear
Release the parking brake
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the
chocks.
Maintenance When Trailer Towing
Your vehicle will need service more often when you’re
pulling a trailer. SeeScheduled Maintenance (Gasoline
Engine) on page 6-4for more information. Things that
are especially important in trailer operation are automatic
transmission uid (don’t overll), engine oil, axle
lubricant, belt, cooling system and brake system. Each of
these is covered in this manual, and the Index will help
you nd them quickly. If you’re trailering, it’s a good idea
to review these sections before you start your trip.
Check periodically to see that all hitch nuts and bolts
are tight.
Trailer Wiring Harness
Your vehicle is equipped with one of the following wiring
harnesses for towing a trailer or hauling a slide-in
camper.
Basic Trailer Wiring
All regular, extended cab and crew cab pickups have an
eight-wire trailer towing harness.
For vehicles not equipped with heavy duty trailering, the
harness is clipped to the vehicle’s frame behind the spare
tire mount. The harness requires the installation of a
trailer connector, which is available through your dealer.
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If your trailer is equipped with electric brakes, you can
get a jumper harness (electric trailer brake control)
with a trailer battery feed fuse from your dealer.
If you need to tow a light-duty trailer with a standard
four-way round pin connector, you can also get an
adapter form your dealer.
Heavy-DutyTrailer Wiring Harness
Package
For vehicles equipped with heavy duty trailering, the
harness is connected to the trailer plug mounted to the
hitch platform.The eight-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
Light Blue: CHMSL*
Red: Battery Feed**
Dark Blue: Trailer Brake
* The Center High-Mounted Stoplamp (CHMSL) wire
is tied next to the trailer wiring harness for use with
a trailer, slide-in camper or cap.
**If you are charging a remote (non-vehicle) battery,
turn on the headlamps to boost the vehicle system
voltage and properly charge the battery.
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Camper/Fifth-Wheel Trailer Wiring Package
The eight-wire camper harness is located under the front
edge of the pickup box on the driver’s side of the vehicle,
attached to the frame bracket. A connector will have to be
added to the wiring harness which connects to the
camper.
The eight-wire 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
Light Blue: Center High-Mounted
Stoplamp (CHMSL)
Red: Battery Feed
Dark Blue: Trailer BrakeIf your 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 and separate CHMSL connector
are located at the rear of the vehicle and are tied to the
vehicle’s frame.
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Electric Brake Control Jumper
{CAUTION:
Be sure to use only the correct trailer brake
harness, the one intended for use on your
vehicle. If you use some other trailer brake
harness, even if it seems to t, your trailer
brakes may not work at all. You could have a
crash in which you or others could be injured.
Use only the trailer brake harness intended for
your vehicle. If it is no longer available to you,
be sure to get a proper replacement from your
dealer.This harness is included with your vehicle as part of the
heavy-duty trailer wiring package.
This harness is for an electric brake controller and
includes a trailer battery feed fuse. It should be installed
by your dealer or a qualied service center.
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