Page 391 of 584

Black plate (105,1)Chevrolet Silverado Owner Manual - 2012
Driving and Operating 9-105
If towing a light‐duty trailer with a
standard four‐way round pin
connector, an adapter is available
from your dealer.
Heavy-DutyTrailer Wiring Harness
Package
For vehicles equipped with heavy
duty trailering, the harness
connector is mounted in the bumper.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
qualified 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 or authorized service
center install the required fuse.
If charging a remote (non-vehicle)
battery, press the Tow/Haul Mode
button, if equipped, 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, or the vehicle is not
equipped with Tow/Haul, turn on
the headlamps as a second way
to boost the vehicle system and
charge the battery.
Page 392 of 584

Black plate (106,1)Chevrolet Silverado Owner Manual - 2012
9-106 Driving and Operating
Camper/Fifth-Wheel Trailer
Wiring Package
The seven-wire camper harness is
located under the front edge of the
pickup box on the driver 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 Brake
If 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, a seven-wire
harness with a seven-pin connector
is located at the rear of the vehicle
and is tied to the vehicle's frame.
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
The harness should be installed by
your dealer or a qualified service
center.
If the vehicle is equipped with an
Integrated Trailer Brake Control
(ITBC) System, the blunt cuts exist,
but are not connected further in the
Page 407 of 584

Black plate (1,1)Chevrolet Silverado Owner Manual - 2012
Vehicle Care 10-1
Vehicle Care
General Information
General Information . . . . . . . . . . 10-2
California Proposition65 Warning . . . . . . . . . . . . . . . . . 10-3
California Perchlorate Materials Requirements . . . . 10-3
Accessories and Modifications . . . . . . . . . . . . . . . 10-3
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 10-4
Hood . . . . . . . . . . . . . . . . . . . . . . . . 10-5
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . 10-6
Engine Oil . . . . . . . . . . . . . . . . . . . 10-7
Engine Oil Life System . . . . . 10-10
Automatic Transmission Fluid (4-Speed Transmission) . . . 10-11
Automatic Transmission Fluid (6-Speed
Transmission) . . . . . . . . . . . . . 10-14
Manual Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . 10-17
Hydraulic Clutch . . . . . . . . . . . . 10-17 Engine Air Cleaner/Filter . . . . 10-17
Cooling System . . . . . . . . . . . . 10-19
Engine Coolant . . . . . . . . . . . . . 10-20
Engine Overheating . . . . . . . . 10-23
Overheated Engine
Protection
Operating Mode . . . . . . . . . . . 10-26
Engine Fan . . . . . . . . . . . . . . . . . 10-26
Power Steering Fluid . . . . . . . 10-27
Washer Fluid . . . . . . . . . . . . . . . 10-28
Brakes . . . . . . . . . . . . . . . . . . . . . 10-28
Brake Fluid . . . . . . . . . . . . . . . . . 10-30
Battery . . . . . . . . . . . . . . . . . . . . . 10-31
Four-Wheel Drive . . . . . . . . . . . 10-32
Front Axle . . . . . . . . . . . . . . . . . . 10-33
Rear Axle . . . . . . . . . . . . . . . . . . 10-34
Noise Control System . . . . . . 10-36
Starter Switch Check . . . . . . . 10-36
Automatic Transmission Shift Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . 10-37
Ignition Transmission Lock Check . . . . . . . . . . . . . . . . . . . . . 10-38
Park Brake and P (Park) Mechanism Check . . . . . . . . 10-38
Wiper Blade Replacement . . . . . . . . . . . . . . 10-39
Glass Replacement . . . . . . . . 10-39
Headlamp Aiming
Headlamp Aiming . . . . . . . . . . 10-39
Bulb Replacement
Bulb Replacement . . . . . . . . . . 10-42
Halogen Bulbs . . . . . . . . . . . . . . 10-42
Headlamps, Front Turn Signal, Sidemarker, and
Parking Lamps . . . . . . . . . . . . 10-42
Pick-Up Box Identification and Fender Marker
Lamps . . . . . . . . . . . . . . . . . . . . 10-43
Taillamps (Chassis Cab Models) . . . . . . . . . . . . . . . . . . . 10-43
Taillamps, Turn Signal, Stoplamps, and Back-Up
Lamps . . . . . . . . . . . . . . . . . . . . 10-44
Center High-Mounted
Stoplamp (CHMSL) and
Cargo Lamp . . . . . . . . . . . . . . 10-44
License Plate Lamp . . . . . . . . 10-45
Replacement Bulbs . . . . . . . . . 10-45
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 449 of 584
Black plate (43,1)Chevrolet Silverado Owner Manual - 2012
Vehicle Care 10-43
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.
4. Install a new bulb into the socket, turn it clockwise, and
press it in until it is tight.
5. Reinstall the lens and the four screws.
Page 450 of 584
Black plate (44,1)Chevrolet Silverado Owner Manual - 2012
10-44 Vehicle Care
Taillamps, Turn Signal,
Stoplamps, and
Back-Up Lamps
To replace one of these bulbs:
1. Open the tailgate. SeeTailgate
on page 2‑10 for more
information.
2. Remove the two rear lamp assembly screws near the
tailgate latch strikerpost and pull
rearward until disengaging the
two outer pins on the taillamp
assembly from the vehicle.
A. Stoplamp/Taillamp/TurnSignal Lamp
B. Back-up Lamp
3. Turn the bulb socket counterclockwise to remove it
from the taillamp assembly.
4. Pull the old bulb straight out from the socket.
5. Press a new bulb into the socket and turn the socket clockwise
into the taillamp assembly.
6. Reinstall the taillamp assembly.
Center High-Mounted
Stoplamp (CHMSL) and
Cargo Lamp
To replace one of these bulbs:
1. Remove the two screws and lift off the lamp assembly.
A. Cargo Lamp
B. Center High-MountedStoplamp (CHMSL) Bulb
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 457 of 584
Black plate (51,1)Chevrolet Silverado Owner Manual - 2012
Vehicle Care 10-51
Instrument Panel Fuse
Block
The instrument panel fuse block
access door is located on the driver
side edge of the instrument panel.
Pull off the cover to access the
fuse block.
The vehicle may not be equipped
with all of the fuses, relays, and
features shown.Fuses Usage1 Rear Seats
2 Rear Accessory
Power Outlet Fuses Usage
3 Steering Wheel
Controls Backlight
4 Driver Door Module
5 Dome Lamps, Driver
Side Turn Signal