brake light GMC SIERRA 2007 Owner's Guide

Maintenance When Trailer Towing
Your vehicle will need service more often when
you’re pulling a trailer. SeeScheduled
Maintenance (Gasoline Engine) on page 623for
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 a seven-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.
If you need to tow a light-duty trailer with a
standard four-way round pin connector, you can
also get an adapter from your dealer.
478

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 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 your vehicle has an auxiliary battery. If your
vehicle does not have an auxiliary battery, have
your dealer or authorized service center install the
required fuse.
If you are 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, you
can turn on the headlamps as a second way to
boost the vehicle system and charge the battery.
479

Camper/Fifth-Wheel Trailer Wiring Package
The seven-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 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 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 is
located at the rear of the vehicle and is tied to the
vehicle’s frame.
480

Electric Brake Control Wiring
Provisions
These wiring provisions are included with your
vehicle as part of the trailer wiring package. These
provisions are for an electric brake controller.
The instrument panel contains blunt cut wires near
the data link connector 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: GroundIt should be installed by your dealer or a qualied
service center.
If your vehicle is equipped with an ITBC, the blunt
cuts exist, but are not connected further in the
harness. If you install an aftermarket trailer brake
controller, 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
you may choose to add, such as a slide-in
camper. If your vehicle has this provision, this
relay will be located on the driver’s side of
the vehicle, next to the underhood electrical center.
481

Brake Wear
Your 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 your vehicle is moving, except when you
are pushing on 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 you hear
the brake wear warning sound, have your
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 Specications on
page 616.
If you have rear drum brakes, they do not have
wear indicators, but if you ever hear a rear brake
rubbing noise, 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 you have
the front brake pads replaced, have the rear
brakes inspected, too.
Brake linings should always be replaced as
complete axle sets.
530

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 PARK (P) 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 your radio or other
accessories on during the jump starting
procedure, they could be damaged. The repairs
would not be covered by your warranty.
Always turn off your radio and other
accessories when jump starting your 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!
533

Fuses Usage
52 Rear Defogger
53 Heated Mirrors
54 SEO B1 Uptter Usage (Battery)
55 Cigarette Lighter, Auxiliary Power Outlet
56Automatic Level Control Compressor
Relay, SEO Uptter Usage
57 Climate Controls (Ignition)
58Engine Control Module, Secondary Fuel
Pump (Ignition)
J-Case Fuses Usage
59 Cooling Fan 1
60 Automatic Level Control Compressor
61 Heavy Duty Anti-lock Brake System
62 Cooling Fan 2
63 Anti-lock Brake System 1
64 Starter
65 Stud 2 (Trailer Brakes)
66 Left Bussed Electrical Center 1
67 Not Used
68 Heated Windshield Washer System
69 Four-Wheel Drive System
J-Case Fuses Usage
70Stud 1 (Trailer Connector Battery
Power) (Optional - 40A Fuse
Required)
71 Mid-Bussed Electrical Center 1
72 Climate Control Blower
73 Tailgate Open/Close Assist
74 Left Bussed Electrical Center 2
Relays Usage
FAN HI Cooling Fan High Speed
FAN LO Cooling Fan Low Speed
ENG EXH VLV Not Used
FAN CNTRL Cooling Fan Control
HDLP LO/HID Low-Beam Headlamp
FOG LAMP Front Fog Lamps
A/C CMPRSR Air Conditioning Compressor
STRTR Starter
PWR/TRN Powertrain
FUEL PMP Fuel Pump
PRK LAMP Parking Lamps
REAR DEFOG Rear Defogger
RUN/CRANK Switched Power
615

A
Accessories and Modications..................... 486
Adding a Snow Plow or Similar
Equipment................................................ 432
Adding Equipment to Your Airbag-Equipped
Vehicle..................................................... 102
Additives, Fuel............................................ 490
Add-On Electrical Equipment....................... 608
Adjustable Throttle and Brake Pedal............ 136
Air Cleaner/Filter, Engine............................. 505
Air Conditioning.........................234, 237, 238
Airbag
Off Light.................................................. 250
Passenger Status Indicator....................... 252
Readiness Light....................................... 250
Airbag Sensing and Diagnostic
Module (SDM).......................................... 656
Airbag System............................................... 83
What Will You See After an Airbag
Inates?................................................. 92
When Should an Airbag Inate?................. 89
Where Are the Airbags?............................. 86
Airbag Systems
Adding Equipment to Your
Airbag-Equipped Vehicle....................... 102
Airbag Off Switch....................................... 93Airbag Systems (cont.)
How Does an Airbag Restrain?.................. 91
Passenger Sensing System....................... 97
Servicing Your Airbag-Equipped Vehicle.... 102
What Makes an Airbag Inate?.................. 91
AM-FM Radio.............................................. 304
Antenna, Fixed Mast................................... 371
Antenna, XM™ Satellite Radio Antenna
System.................................................... 371
Anti-Lock Brake System.............................. 379
Anti-Lock Brake, System Warning Light....... 257
Appearance Care
Aluminum or Chrome-Plated Wheels........ 603
Care of Safety Belts................................ 601
Chemical Paint Spotting........................... 605
Cleaning Exterior Lamps/Lenses.............. 602
Cleaning the Inside of Your Vehicle.......... 597
Fabric/Carpet........................................... 599
Finish Care.............................................. 602
Finish Damage......................................... 605
Instrument Panel, Vinyl, and Other
Plastic Surfaces.................................... 600
Leather.................................................... 600
Sheet Metal Damage............................... 604
Tires........................................................ 604
Underbody Maintenance........................... 605
Vehicle Care/Appearance Materials.......... 606
665

Appearance Care (cont.)
Washing Your Vehicle.............................. 601
Weatherstrips........................................... 601
Windshield and Wiper Blades................... 603
Ashtray....................................................... 233
Audio System.............................................. 300
AM-FM Radio.......................................... 304
Audio Steering Wheel Controls................. 368
Care of Your CD and DVD Player............ 371
Care of Your CDs and DVDs................... 370
Fixed Mast Antenna................................. 371
Navigation/Radio System, see Navigation
Manual................................................. 355
Radio with CD................................306, 312
Rear Seat Audio (RSA)............................ 366
Setting the Time...................................... 301
Theft-Deterrent Feature............................ 368
Understanding Radio Reception............... 369
XM™ Satellite Radio Antenna System...... 371
Audio System(s)
Radio with CD and DVD.......................... 322
Automatic Headlamp System....................... 223
Automatic Transmission
Fluid........................................................ 508
Operation................................................. 138
Auxiliary Roof Mounted Lamp Switch.......... 225B
Battery........................................................ 531
Electric Power Management..................... 227
Run-Down Protection............................... 228
Before Leaving on a Long Trip.................... 414
Brake
Emergencies............................................ 381
Parking.................................................... 162
Brakes........................................................ 528
System Warning Light.............................. 256
Braking....................................................... 378
Braking in Emergencies............................... 381
Break-In, New Vehicle................................. 132
Bulb Replacement....................................... 543
Center High-Mounted Stoplamp (CHMSL)
and Cargo Lamp.................................. 545
Halogen Bulbs......................................... 544
Headlamps............................................... 544
License Plate Lamps................................ 548
Pickup Box Identication and Fender
Marker Lamps...................................... 546
Replacement Bulbs.................................. 549
Taillamps, Turn Signal, Stoplamps and
Back-up Lamps..................................... 546
Buying New Tires........................................ 568
666

K
Keyless Entry System................................. 110
Keys........................................................... 109
L
Labeling, Tire Sidewall................................. 551
Lamps
Auxiliary Roof Mounted Lamp.................. 225
Cargo...................................................... 227
Dome....................................................... 226
Dome Lamp Override............................... 226
Exterior.................................................... 221
Puddle..................................................... 224
Reading................................................... 226
LATCH System
Child Restraints......................................... 58
Latches, Seatback......................................... 19
License Plate Lamps................................... 548
Light
Airbag Off................................................ 250
Airbag Readiness..................................... 250
Anti-Lock Brake System Warning............. 257
Brake System Warning............................. 256
Charging System..................................... 254Light (cont.)
Cruise Control.......................................... 265
Fog Lamp................................................ 265
Four-Wheel-Drive..................................... 265
Highbeam On.......................................... 265
Low Fuel Warning.................................... 267
Malfunction Indicator................................ 260
Oil Pressure............................................. 264
Passenger Airbag Status Indicator............ 252
Passenger Safety Belt Reminder.............. 249
Safety Belt Reminder............................... 249
Security................................................... 264
StabiliTrak
®Indicator................................ 258
Tire Pressure........................................... 259
Tow/Haul Mode........................................ 266
Lighting
Entry........................................................ 226
Exit.......................................................... 226
Loading Your Vehicle................................... 425
Locking Rear Axle....................................... 381
Lockout Protection....................................... 120
Locks
Delayed Locking...................................... 119
Door........................................................ 118
Lockout Protection................................... 120
672