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Federal law prohibits the following acts or the causing
thereof:1. The removal or rendering inoperative by any person, other than for purposes of maintenance,
repair or replacement, of any device or element of
design incorporated into any new vehicle for the
purpose of noise control, prior to its sale or delivery
to the ultimate purchaser or while it is in use; or
2. The use of the vehicle after such device or element of design has been removed or rendered
inoperative by any person.
Among those acts presumed to constitute tampering are
the acts listed below.
Insulation:
.Removal of the noise shields or any underhood
insulation.
Engine:
.Removal or rendering engine speed governor,
if the vehicle has one, inoperative so as to allow
engine speed to exceed manufacturer
specifications.
Fan and Drive:
.Removal of fan clutch, if the vehicle has one,
or rendering clutch inoperative.
.Removal of the fan shroud, if the vehicle has one.
Air Intake:
.Removal of the air cleaner silencer.
.Modification of the air cleaner.
Exhaust:
.Removal of the muffler and/or resonator.
.Removal of the exhaust pipes and exhaust pipe
clamps.
Headlamp Aiming
The vehicle has a visual optical headlamp aiming
system. The aim of the headlamps have been preset at
the factory and should need no further adjustment.
However, if the vehicle is damaged in a crash, the aim
of the headlamps can be affected and adjustment can
be necessary.
If oncoming vehicles flash their high beams at you, this
can mean the vertical aim of your headlamps needs to
be adjusted.
It is recommended that the vehicle is taken to your
dealer for service if the headlamps need to be adjusted.
It is possible however, to re-aim the headlamps as
described.
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The vehicle should:
.Be placed so the headlamps are 25 ft. (7.6 m) 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 normally loaded with a full tank of fuel and one
person or 160 lbs (75 kg) sitting on the driver seat.
.Have tires properly inflated.
.Have the spare tire is 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 Release
on page 6‑15for more information.
2. 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.
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4. At a wall measure from the ground upward (A) tothe recorded distance from Step 3 and mark it.
5. Draw or tape a horizontal line (B) on the wall or flat surface the width of the vehicle at the height of the
mark in Step 4.
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 headlamp aiming screws, whichare under the hood near each headlamp assembly.
The adjustment screw can be turned with a
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.
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9. Make sure that the light from the headlamp ispositioned 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.
Bulb Replacement
For the proper type of replacement bulbs, see
Replacement Bulbs on page 6‑62.
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
To replace one of these bulbs:
1. Open the hood. See Hood Release
on page 6‑15for more information.
2. If you are replacing the bulb on the passenger side remove the Engine Air Cleaner cover. See Engine
Air Cleaner/Filter
on page 6‑21for more
information.
3. Reach in and access the bulb sockets from inside the engine compartment.
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4. Turn the bulb socket counterclockwise to remove itfrom 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 socket.
7. Plug in the electrical connector to the new bulb socket.
8. Reinstall the new bulb socket into the headlamp assembly and turn it clockwise to secure.
9. Close the hood.
Center High-Mounted Stoplamp
(CHMSL) and Cargo Lamp
To replace one of these bulbs:
1. Remove the screws and lift off the lamp assembly.
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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.
License Plate Lamp
To replace one of these bulbs: 1. Reach under the rear bumper for the bulb socket.
2. Turn the bulb socket counterclockwise and pull the bulb socket out of the connector.
3. Pull the old bulb from the bulb socket, keeping the bulb straight as you pull it out.
4. Install the new bulb.
5. Reverse Steps 1 through 3 to reinstall the bulb socket.
Replacement Bulbs
Exterior Lamp Bulb Number
Back-up Lamp 3047 or 921
Back-up Lamp* 1156
Cargo Lamp and Center
High-Mounted Stoplamp (CHMSL) 912
Fender Marker Lamp W5WLL
High-Beam Headlamp 9005
Low-Beam Headlamp H11
License Plate Lamp 168
Sidemarker Lamp/Stoplamp/Taillamp/
Turn Signal Lamp 3047
Stoplamp/Turn Signal Lamp/Taillamp* 1157
* Chassis Cab Models
For replacement bulbs not listed here, contact your
dealer.
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If you need to replace any of the wheels, wheel bolts,
wheel nuts or Tire Pressure Monitor System (TPMS)
sensors, replace them only with new GM original
equipment parts. This way, you will be sure to have the
right wheel, wheel bolts, wheel nuts, and TPMS sensors
for the vehicle.
{WARNING:
Using the wrong replacement wheels, wheel bolts,
or wheel nuts on your vehicle can be dangerous.
It could affect the braking and handling of your
vehicle, make your tires lose air and make you
lose control. You could have a collision in which
you or others could be injured. 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
100, 1,000 and 6,000 miles (160, 1 600 and 10 000 km)
of driving. For proper torque, see
“Wheel Nut Torque”
under Capacities and Specifications on page 6‑126.
See Changing a Flat Tire
on page 6‑90for more
information.
Used Replacement Wheels
{WARNING:
Putting a used wheel on the vehicle is dangerous.
You cannot know how it has been used or how far
it has been driven. It could fail suddenly and
cause a crash. If you have to replace a wheel, use
a new GM original equipment wheel.
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FusesUsage
5Engine Control Module, Throttle
Control
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
17 Air Conditioning Compressor
18 Oxygen Sensors
19 Transmission Controls (Ignition)
20 Fuel Pump
21 Fuel System Control Module
22 Not Used
Fuses Usage
23 Not Used
24Fuel 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 Lights 2
34 Sunroof
35 Key Ignition System, Theft Deterrent
System
36 Windshield Wiper
37 SEO B2 Upfitter Usage (Battery)
38 Electric Adjustable Pedals
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