Page 446 of 584

Black plate (40,1)Chevrolet Silverado Owner Manual - 2012
10-40 Vehicle Care
The vehicle should:
.Be placed so the headlamps
are 7.6 m (25 ft) from a
light‐colored wall.
.Have all four tires on a level
surface which is level all the way
to the wall.
.Be placed so it is perpendicular
to the wall.
.Not have any snow, ice, or mud
on it.
.Be fully assembled and all other
work stopped while headlamp
aiming is being performed.
.Be loaded with a full tank of
fuel and one person or 75 kg
(160 lbs) sitting on the
driver seat.
.Have the tires properly inflated.
.Have the spare tire in its proper
location in the vehicle.Headlamp aiming is done with the
vehicle's low-beam headlamps.
The high-beam headlamps will be
correctly aimed if the low-beam
headlamps are aimed properly.
To adjust the vertical aim:
1. Open the hood. See
Hood on
page 10‑52. Locate the aim dot on the lens of the low‐beam headlamp. 3. Record the distance from the
ground to the aim dot on the
low‐beam headlamp.
4. At a wall, measure from the
ground upward (A) to the
recorded distance from
Step 3 and mark it.
5. Draw or tape a horizontal line (B) on the wall the width of the
vehicle at the height of the
mark in Step 4.
Page 447 of 584

Black plate (41,1)Chevrolet Silverado Owner Manual - 2012
Vehicle Care 10-41
Notice:Do not cover a headlamp
to improve beam cut-off when
aiming. Covering a headlamp may
cause excessive heat build-up
which may cause damage to the
headlamp.
6. Turn on the low-beam
headlamps and place a piece
of cardboard or equivalent in
front of the headlamp not being
adjusted. This allows only the
beam of light from the headlamp
being adjusted to be seen on the
flat surface.
7. Locate the vertical headlampaiming screws, which are under
the hood near each headlamp
assembly.
The adjustment screw can be
turned with an E8 Torx
®socket.
8. Turn the vertical aiming screw until the headlamp beam is
aimed to the horizontal tape
line. Turn it clockwise or
counterclockwise to raise or
lower the angle of the beam.
9. Make sure that the light from theheadlamp is positioned at the
bottom edge of the horizontal
tape line. The lamp on the
left (A) shows the correct
headlamp aim. The lamp on the
right (B) shows the incorrect
headlamp aim.
10. Repeat Steps 7 through 9 for the opposite headlamp.
Page 448 of 584

Black plate (42,1)Chevrolet Silverado Owner Manual - 2012
10-42 Vehicle Care
Bulb Replacement
For the proper type of replacement
bulbs, seeReplacement Bulbs on
page 10‑45.
For any bulb‐changing procedure
not listed in this section, contact
your dealer.
Halogen Bulbs
{WARNING
Halogen bulbs have pressurized
gas inside and can burst if you
drop or scratch the bulb. You or
others could be injured. Be sure
to read and follow the instructions
on the bulb package.
Headlamps, Front Turn
Signal, Sidemarker, and
Parking Lamps
A. Park/Turn Signal/
Sidemarker Lamp
B. Low‐Beam Headlamp
C. High‐Beam Headlamp 1. Open the hood. See
Hood on
page 10‑5
2. If you are replacing the bulb on the passenger side, remove the
Engine Air Cleaner cover.
See Engine Air Cleaner/Filter on
page 10‑17 for more information.
3. Reach in and access the bulb sockets from inside the engine
compartment.
4. Turn the bulb socket counterclockwise to remove it
from the headlamp assembly
and pull it straight out.
5. Unplug the electrical connector from the old bulb by releasing
the clips on the bulb socket.
6. Replace it with a new bulb.
7. Plug in the electrical connector.
8. Reinstall the new bulb socket into the headlamp assembly and
turn it clockwise to secure.
Page 451 of 584

Black plate (45,1)Chevrolet Silverado Owner Manual - 2012
Vehicle Care 10-45
2. On the reverse side of the lampassembly, remove the bulb
socket by turning it one quarter
turn counterclockwise and pull it
straight out.
3. Remove the bulb by pulling it straight out of the socket.
4. Install the bulb by pushing the bulb straight into the socket.
5. Install the bulb socket into the lamp asembly by turning it
one quarter turn clockwise.
6. Reinstall the lamp assembly and tighten the screws.License Plate Lamp
To replace one of these bulbs:
1. Reach under the rear bumper forthe bulb socket.
2. Turn the bulb socketcounterclockwise and pull the
bulb socket out of the lamp
assembly.
3. Pull the old bulb straight out from the bulb socket.
4. Install the new bulb.
5. Reverse Steps 1 and 2 to reinstall the bulb socket.
Replacement Bulbs
Exterior Lamp Bulb Number
Back-up Lamp 921LL
Back-up Lamp* 1156
Cargo Lamp
and Center
High-Mounted
Stoplamp
(CHMSL) 912LL
Fender Marker
Lamp (If Equipped) W5WLL
High-Beam
Headlamp 9005
Low-Beam
Headlamp H11
Page 452 of 584

Black plate (46,1)Chevrolet Silverado Owner Manual - 2012
10-46 Vehicle Care
Exterior Lamp BulbNumber
License
Plate Lamp 168
Sidemarker Lamp/
Stoplamp/Taillamp/
Turn Signal Lamp 3047K
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.
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.
Page 454 of 584
Black plate (48,1)Chevrolet Silverado Owner Manual - 2012
10-48 Vehicle Care
FusesUsage
1 Right Trailer
Stop/Turn Lamp
2 Electronic
Suspension Control,
Automatic Level
Control Exhaust Fuses
Usage
3 Left Trailer
Stop/Turn Lamp
4 Engine Controls
5 Engine Control
Module, Throttle
Control Fuses
Usage
6 Trailer Brake
Controller
7 Front Washer
8 Oxygen Sensor
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
Page 455 of 584

Black plate (49,1)Chevrolet Silverado Owner Manual - 2012
Vehicle Care 10-49
FusesUsage
17 Air Conditioning
Compressor
18 Oxygen Sensors
19 Transmission
Controls (Ignition)
20 Fuel Pump
21 Fuel System Control
Module
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 Fuses
Usage
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
36 Windshield Wiper
37 SEO B2 Upfitter
Usage (Battery)
38 Electric Adjustable
Pedals
39 Climate Controls
(Battery) Fuses
Usage
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
51 Heated Mirrors
Page 456 of 584

Black plate (50,1)Chevrolet Silverado Owner Manual - 2012
10-50 Vehicle Care
FusesUsage
52 SEO B1 Upfitter
Usage (Battery)
53 Cigarette Lighter,
Auxiliary 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