2012 GMC SIERRA 1500 headlamp

Black plate (40,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
10-40 Vehicle Care
3. When replacing a bulb on thepassenger side, remove the
Engine Air Cleaner cover. See
Engine Air Cleaner/Filter on
page 10‑17 for more information.
4. Reach in and access the bulb sockets from inside the engine
compartment.
5. Turn the bulb socket counterclockwise to remove it
from the headlamp assembly
and pull it straight out.
6. Unplug the electrical connector from the old bulb by releasing
the clips on the bulb socket.
7. Replace it with a new bulb.
8. Plug in the electrical connector.
9. Reinstall the new bulb socket into the headlamp assembly and
turn it clockwise to secure.Pick-Up Box Identification
and Fender Marker
Lamps
The pick-up box identification lamps
are LEDs. For replacement of the
LED lighting assembly contact your
dealer.
To replace a pickup box fender
marker lamp bulb:
1. Press the tab from the back toremove the lamp.
2. Turn the bulb socket counterclockwise to remove
from the lamp assembly.
3. Gently pry the bulb from the socket.
4. Install the new bulb in socket.
5. Reinstall socket into lamp assembly.
6. Reinstall the lamp assembly.
Taillamps (Chassis Cab
Models)
A. Backup Lamp
B. Stoplamp/Taillamp/Turn Signal Lamp
To replace one of these bulbs:
1. Remove the four screws.
2. Lift the lens off the lamp assembly.
3. Turn the old bulb counterclockwise and pull the
it straight out from the socket.

Black plate (43,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Vehicle Care 10-43
3. Turn the bulb socket (C)one‐quarter turn to release the
bulb socket from the lamp
housing (A).
4. Pull the bulb (B) from the bulb socket (C).
5. Reverse the steps to install.
Replacement Bulbs
Exterior Lamp Bulb Number
Back-up Lamp 921
Back-up Lamp* 1156
Cargo Lamp
and Center
High-Mounted
Stoplamp
(CHMSL) 912
Fender Marker W5WLL
Front Turn Signal
Lamp, Sidemarker
Lamp, and
Parking Lamp 3157AExterior Lamp Bulb
Number
High-Beam
Headlamp 9005
Low-Beam
Headlamp H11
License
Plate Lamp 168
Stoplamp/Taillamp/
Turn Signal Lamp 3047K
Sidemarker Lamp 194
Stoplamp/Turn
Signal Lamp/
Taillamp* 1157
* Chassis Cab Models
For replacement bulbs not listed
here, contact your dealer.
Electrical System
Electrical System
Overload
The vehicle has fuses and circuit
breakers to protect against an
electrical system overload.
When the current electrical load is
too heavy, the circuit breaker opens
and closes, protecting the circuit
until the current load returns to
normal or the problem is fixed.
This greatly reduces the chance of
circuit overload and fire caused by
electrical problems.
Fuses and circuit breakers protect
power devices in the vehicle.
Replace a bad fuse with a new one
of the identical size and rating.
If there is a problem on the road
and a fuse needs to be replaced,
the same amperage fuse can be
borrowed. Choose some feature of
the vehicle that is not needed to use
and replace it as soon as possible.

Black plate (44,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
10-44 Vehicle Care
Headlamp Wiring
An electrical overload may cause
the lamps to go on and off, or in
some cases to remain off. Have
the headlamp wiring checked right
away if the lamps go on and off or
remain off.
Windshield Wipers
If the wiper motor overheats due to
heavy snow or ice, the windshield
wipers will stop until the motor cools
and will then restart.
Although the circuit is protected
from electrical overload, overload
due to heavy snow or ice may
cause wiper linkage damage.
Always clear ice and heavy snow
from the windshield before using the
windshield wipers.
If the overload is caused by an
electrical problem and not snow or
ice, be sure to get it fixed.
Fuses and Circuit
Breakers
If the vehicle is a hybrid, see the
hybrid supplement for more
information.
The wiring circuits in the vehicle
are protected from short circuits
by a combination of fuses, circuit
breakers and fusible thermal links.
This greatly reduces the chance of
fires caused by electrical problems.
Look at the silver-colored band
inside the fuse. If the band is broken
or melted, replace the fuse. Be sure
you replace a bad fuse with a new
one of the identical size and rating.If you ever have a problem on the
road and don't have a spare fuse,
you can borrow one that has the
same amperage. Just pick some
feature of your vehicle that you can
get along without–
like the radio or
accessory power outlet– and use its
fuse, if it is the correct amperage.
Replace it as soon as you can.
Engine Compartment
Fuse Block
If the vehicle has a diesel engine,
see the Duramax Diesel supplement
for more information.
If the vehicle is a hybrid, see the
hybrid supplement for more
information.

Black plate (46,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
10-46 Vehicle Care
FusesUsage
9 Antilock Brakes System 2
10 Trailer Back-up Lamps
11 Driver Side Low-Beam
Headlamp
12 Engine Control Module
(Battery)
13 Fuel Injectors, Ignition
Coils (Right Side)
14 Transmission Control
Module (Battery)
15 Vehicle Back-up Lamps
16 Passenger Side
Low-Beam Headlamp
17 Air Conditioning
Compressor
18 Oxygen Sensors
19 Transmission Controls
(Ignition)
20 Fuel Pump
21 Fuel System Control
Module Fuses
Usage
22 Not Used
23 Not Used
24 Fuel Injectors, Ignition
Coils (Left Side)
25 Trailer Park Lamps
26 Driver Side Park Lamps
27 Passenger Side Park
Lamps
28 Fog Lamps
29 Horn
30 Passenger Side
High-Beam Headlamp
31 Daytime Running
Lamps (DRL)
32 Driver Side High-Beam
Headlamp
33 Daytime Running Lamps 2
34 Sunroof
35 Key Ignition System, Theft
Deterrent System Fuses
Usage
36 Windshield Wiper
37 SEO B2 Upfitter Usage
(Battery)
38 Electric Adjustable Pedals
39 Climate Controls (Battery)
40 Airbag System (Ignition)
41 Amplifier
42 Audio System
43 Miscellaneous (Ignition),
Cruise Control
44 Not Used
45 Airbag System (Battery)
46 Instrument Panel Cluster
47 Power Take-Off
48 Auxiliary Climate Control
(Ignition)
49 Center High-Mounted
Stoplamp (CHMSL)
50 Rear Defogger

Black plate (47,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Vehicle Care 10-47
FusesUsage
51 Heated Mirrors
52 SEO B1 Upfitter Usage
(Battery)
53 Accessory Power Outlet
54 SEO Upfitter Usage
55 Climate Controls (Ignition)
56 Engine Control Module,
Secondary Fuel Pump
(Ignition)
J-Case Fuses Usage
57 Cooling Fan 1
58 Not Used
59 Heavy Duty Antilock
Brake System
60 Cooling Fan 2
61 Antilock Brake
System 1 J-Case
Fuses Usage
62 Starter
63 Stud 2 (Trailer Brakes)
64 Left Bussed Electrical
Center 1
65 Not Used
66 Not Used
67 Transfer Case
68 Stud 1 (Trailer
Connector
Battery Power)
(Optional - 40A Fuse
Required)
69 Mid-Bussed Electrical
Center 1
70 Climate Control Blower
71 Not Used
72 Left Bussed Electrical
Center 2 Relays
Usage
FAN HI Cooling Fan High
Speed
FAN LO Cooling Fan Low
Speed
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/CRNK Switched Power

Black plate (73,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Vehicle Care 10-73
{WARNING
Using the wrong replacement
wheels, wheel bolts, or wheel
nuts can be dangerous. It could
affect the braking and handling of
the vehicle. Tires can lose air,
and cause loss of control, causing
a crash. Always use the correct
wheel, wheel bolts, and wheel
nuts for replacement.Notice:
The wrong wheel can
also cause problems with
bearing life, brake cooling,
speedometer or odometer
calibration, headlamp aim,
bumper height, vehicle ground
clearance, and tire or tire chain
clearance to the body and
chassis.
Whenever a wheel, wheel bolt,
or wheel nut is replaced on a dual
wheel setup, check the wheel
nut torque after 160, 1 600 and
10 000 km (100, 1,000 and 6,000 mi)
of driving. For proper torque,
see “Wheel Nut Torque” under
Capacities and Specifications on
page 12‑2.
See If a Tire Goes Flat on
page 10‑75 for more information. Used Replacement Wheels{WARNING
Replacing a wheel with a used
one is dangerous. How it has
been used or how far it has been
driven may be unknown. It could
fail suddenly and cause a crash.
When replacing wheels, use a
new GM original equipment
wheel.

Black plate (10,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
11-10 Service and Maintenance
Hoses
Hoses transport fluids and should
be regularly inspected to ensure
that there are no cracks or leaks.
With a multi‐point inspection, your
dealer can inspect the hoses and
advise if replacement is needed.
Lamps
Properly working headlamps,
taillamps, and brake lamps are
important to see and be seen on
the road.
.Signs that the headlamps need
attention include dimming, failure
to light, cracking, or damage.
The brake lamps need to be
checked periodically to ensure
that they light when braking.
.With a multi‐point inspection,
your dealer can check the lamps
and note any concerns.Shocks and Struts
Shocks and struts help aid in control
for a smoother ride.
.Signs of wear may include
steering wheel vibration,
bounce/sway while braking,
longer stopping distance,
or uneven tire wear.
.As part of the multi‐point
inspection, trained dealer
technicians can visually inspect
the shocks and struts for
signs of leaking, blown seals,
or damage, and can advise
when service is needed.
Tires
Tires need to be properly inflated,
rotated, and balanced. Maintaining
the tires can save money, fuel, and
can reduce the risk of tire failure.
.Signs that the tires need to be
replaced include three or more
visible treadwear indicators; cord
or fabric showing through the rubber; cracks or cuts in the
tread or sidewall; or a bulge or
split in the tire.
.Trained dealer technicians can
inspect and recommend the
right tires. Your dealer can also
provide tire/wheel balancing
services to ensure smooth
vehicle operation at all speeds.
Your dealer sells and services
name brand tires.
Vehicle Care
To help keep the vehicle looking
like new, vehicle care products are
available from your dealer. For
information on how to clean and
protect the vehicle’s interior and
exterior, see Interior Care on
page 10‑101 andExterior Care on
page 10‑98.

Black plate (1,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
INDEX i-1
A
Accessories andModifications . . . . . . . . . . . . . . . . . 10-3
Accessory Power . . . . . . . . . . . . . . 9-29
Active Fuel Management
®. . . . . 9-32
Add-On Electrical Equipment . . . . . . . . . . . . . . . . . . 9-105
Adding a Snow Plow or Similar Equipment . . . . . . . . . . . 9-106
Additional Information, OnStar
®. . . . . . . . . . . . . . . . . . . . . . 14-5
Adjustable Throttle and Brake Pedal . . . . . . . . . . . . . . . . . . 9-25
Adjustments Lumbar, Front Seats . . . . . . . . . . . 3-4
Air Cleaner/Filter, Engine . . . . . 10-17
Air Vents . . . . . . . . . . . . . . . . . . . . . . 8-10
Airbag System
Check . . . . . . . . . . . . . . . . . . . . . . . . 3-38
How Does an AirbagRestrain? . . . . . . . . . . . . . . . . . . . 3-27
Passenger Sensing System . . . . . . . . . . . . . . . . . . . . . . 3-32
What Makes an Airbag Inflate? . . . . . . . . . . . . . . . . . . . . . . 3-27 Airbag System (cont'd)
What Will You See after an
Airbag Inflates? . . . . . . . . . . . . . 3-27
When Should an Airbag
Inflate? . . . . . . . . . . . . . . . . . . . . . . 3-25
Where Are the Airbags? . . . . . . 3-23
Airbags Adding Equipment to theVehicle . . . . . . . . . . . . . . . . . . . . . . 3-37
Light On-Off . . . . . . . . . . . . . . . . . . 5-19
On-Off Light . . . . . . . . . . . . . . . . . . 5-19
On-Off Switch . . . . . . . . . . . . . . . . 3-29
Passenger Status Indicator . . . 5-21
Readiness Light . . . . . . . . . . . . . . 5-18
Servicing Airbag-Equipped Vehicles . . . . . . . . . . . . . . . . . . . . . 3-36
System Check . . . . . . . . . . . . . . . . 3-21
Alarm System
Anti-theft . . . . . . . . . . . . . . . . . . . . . . 2-11
AM-FM Radio . . . . . . . . . . . . . . . . . . . 7-9
Antenna Satellite Radio . . . . . . . . . . . . . . . . 7-15
Anti-theft
Alarm System . . . . . . . . . . . . . . . . 2-11
Alarm System Messages . . . . . 5-45 Antilock Brake
System (ABS) . . . . . . . . . . . . . . . . 9-53
Warning Light . . . . . . . . . . . . . . . . . 5-26
Appearance Care Exterior . . . . . . . . . . . . . . . . . . . . . 10-98
Interior . . . . . . . . . . . . . . . . . . . . . 10-101
Ashtrays . . . . . . . . . . . . . . . . . . . . . . . 5-11
Assistance Program,
Roadside . . . . . . . . . . . . . . . 13-7, 13-9
Audio Players . . . . . . . . . . . . . . . . . 7-15 CD . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-15
CD/DVD . . . . . . . . . . . . . . . . . . . . . . 7-21
Audio System Fixed Mast Antenna . . . . . . . . . . 7-15
Radio Reception . . . . . . . . . . . . . . 7-14
Rear Seat (RSA) . . . . . . . . . . . . . 7-46
Theft-Deterrent Feature . . . . . . . . 7-2
Automatic Door Locks . . . . . . . . . . . . . . . . . . . . 2-8
Headlamp System . . . . . . . . . . . . . 6-4
Transmission . . . . . . . . . . . . . . . . . 9-35
TransmissionFluid . . . . . . . . . . . . . . . 10-11, 10-14