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To replace the front turn signal, sidemarker,
and/or parking lamp bulb(s):
1. Use a small tool to unlatch the outboardclip on the lamp by pushing inboard and
prying the lamp assembly forward.
2. Remove the lamp from the grille.
3. Turn the bulb socket counterclockwise one-quarter turn and remove it from the
lamp assembly.
4. Remove the bulb from the socket by pulling it straight out.
5. Replace the bulb.
6. Turn the bulb socket clockwise to reinstall it in the lamp assembly.
7. Reinstall the lamp assembly into the grille until the outboard clip snaps into
place.
Taillamps
To replace a taillamp/turn signal lamp or
back-up lamp bulb:
1. Remove the two inboard nuts from theinside of the taillamp assembly.
2. The third nut (3) is under the appliquepiece (2) above the lamp. Remove the
two inboard applique nuts. Pull the
applique (2) straight rearward slightly to
clear the studs. Then rotate the
applique (2) just far enough to gain
access to the outer push pins (1).
3. Carefully disconnect the push pins (1) from the applique bracket.
4. Remove the third nut (3) from the upper outboard side of the lamp.
5. Remove the taillamp assembly from the vehicle.
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6. Remove the taillamp/turn signal lamp (1)or back-up lamp (2) bulb socket by
turning it counterclockwise one-quarter
turn and pulling it out of the lamp
assembly.
7. Remove the bulb by pulling it straight out.
8. Push the new bulb into the socket.
9. Reinstall the bulb socket by turning it clockwise into the lamp assembly.
10. Reverse Steps 1–5 to reinstall the taillamp assembly and applique.
Center High-Mounted Stoplamp
(CHMSL)
The Center High-Mounted Stoplamp (CHMSL)
is above the rear doors at the center of the
vehicle.
To replace a bulb:
1. Remove the two screws from the CHMSLassembly.
2. Remove the CHMSL assembly.
3. Turn the bulb socket counterclockwise one-quarter turn to remove it from the
lamp assembly. 4. Pull the old bulb straight out of the
socket and push the new bulb into the
socket.
5. Turn the bulb socket clockwise one-quarter turn to install it in the lamp
assembly.
6. Reinstall the CHMSL assembly and two screws.
Do not block or damage the CHMSL when
items are loaded on the roof of the vehicle.
License Plate Lamp
1. Bulb Socket
2. License Plate Bulb Assembly
3. Screws
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To replace one of these bulbs:1. Remove the screws (3) that secure the license plate bulb assembly (2).
2. Turn the bulb socket (1) counterclockwise and pull the bulb straight out of the
socket.
3. Install the new bulb.
4. Reverse Steps 1 and 2 to reinstall the license plate bulb assembly.
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. 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
The wiring circuits in the vehicle are
protected from short circuits by a
combination of fuses and circuit breakers.
This greatly reduces the chance of damage
caused by electrical problems.
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{Danger
Fuses and circuit breakers are marked
with their ampere rating. Do not exceed
the specified amperage rating when
replacing fuses and circuit breakers. Use
of an oversized fuse or circuit breaker can
result in a vehicle fire. You and others
could be seriously injured or killed.
{Warning
Installation or use of fuses that do not
meet GM’s original fuse specifications is
dangerous. The fuses could fail, and result
in a fire. You or others could be injured
or killed, and the vehicle could be
damaged.See
Accessories and Modifications 0178 and
General Information 0178.
To check a fuse, look at the silver-colored
band inside the fuse. If the band is broken
or melted, replace the fuse. Be sure to
replace a bad fuse with a new one of the
identical size and rating.
Fuses of the same amperage can be
temporarily borrowed from another fuse
location, if a fuse goes out. Replace the fuse
as soon as possible.
Engine Compartment Fuse Block
The fuse block is in the engine compartment
on the driver side of the vehicle.
Vehicles with Upfitter Content
See www.gmupfitter.com for upfitter
provisions and best practices.
Caution
Spilling liquid on any electrical
component on the vehicle may damage
it. Always keep the covers on any
electrical component.
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FusesUsage
68 Auxiliary stoplamps
69 External power for trailer
70 Upfitter stoplamps 71 Fuel heater/FlexFuel sensor
72 Body control module 6
73 Lighter/Data link connector
74 Front blower 75 Engine control module
76 Soot sensors (Diesel only)
77 O2 sensor 1
78 Engine control module/ Powertrain signal 1
79 Ignition coils/injectors - even Relays
Usage
15 Run/Crank
37 NOX Sensor (Diesel only)
38 Fuel pump
39 Crank
40 A/C compressor 48 Electro viscous fan clutch (Diesel only)
49 Powertrain 50 –
57 –
60 – Auxiliary Fuse Block
This component is near the fuse block in the
engine compartment
Fuses Usage
MR-1 Upfitter 1
MR-2 Upfitter 2
MR-3 Upfitter power control
Relays Usage
MR Rel 1 Upfitter 1
MR Rel 2 Upfitter 2
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Mega Fuse Holder
FuseUsage
1 Starter motor
Floor Console Fuse Block
The floor console fuse block is under the driver seat.
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The vehicle may not be equipped with all of
the fuses, relays, and features shown.Mini-Fuses Usage
F1 –
F2 Steering wheel sensor
F3 Auxiliary parking lamps
F4 Front parking lamps F5 Trailer parking lamps
F6 Upfitter/Parking lamps F7 Right rear parking lamp
F8 Left rear parking lamp
F9 Exterior rear mirror switch/ Door
lock-unlock control
upfitter/Front camera
module
F10 Airbag/Automatic occupant sensing
F11 –/OnStar
F12 –
F13 HVAC 2
F14 HVAC 1 F15 Reflected LED display Mini-Fuses Usage
F16 Upfitter aux 1/Gas ambulance
F17 Heated outside mirrors
F18 Rear window defogger
F19 Compass
F20 Radio/Chime/SiriusXM satellite radio
F21 Remote function actuator/Tire pressure
monitor
F22 Ignition switch/Discrete logic ignition sensor
F23 Instrument cluster
F24 –
F25 HVAC control
F26 Auxiliary/Trailer reverse lamps
F27 Reverse tail lamps
F28 Upfitter 2/Reading lamps/Ambulance
F29 Rear blower
F30 Upfitter/Courtesy lamps Mini-Fuses Usage
F31 Front door lock
F32 Rear door lock
F33 Cargo door unlock
F34 Front passenger door unlock
F35 Rear passenger door unlock
F36 Driver door unlock F37 –
F38 –
Relays Usage K1 Run
K2 –
K3 Parking lamps
K4 Upfitter 2 K5 Rear window defogger
K6 Retained accessory power
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Different Size Tires and Wheels
If wheels or tires are installed that are a
different size than the original equipment
wheels and tires, vehicle performance,
including its braking, ride and handling
characteristics, stability, and resistance to
rollover may be affected. If the vehicle has
electronic systems such as antilock brakes,
rollover airbags, traction control, electronic
stability control, or All-Wheel Drive, the
performance of these systems can also be
affected.
{Warning
If different sized wheels are used, there
may not be an acceptable level of
performance and safety if tires not
recommended for those wheels are
selected. This increases the chance of a
crash and serious injury. Only use GM
specific wheel and tire systems developed
for the vehicle, and have them properly
installed by a GM certified technician.
See Buying New Tires 0223 and
Accessories and Modifications 0178.
Uniform Tire Quality Grading
The following information relates to the
system developed by the United States
National Highway Traffic Safety
Administration (NHTSA), which grades
tires by treadwear, traction, and
temperature performance. This applies
only to vehicles sold in the United
States. The grades are molded on the
sidewalls of most passenger car tires.
The Uniform Tire Quality Grading
(UTQG) system does not apply to deep
tread, winter tires, compact spare tires,
tires with nominal rim diameters of
10 to 12 inches (25 to 30 cm), or to some
limited-production tires.
While the tires available on General
Motors passenger cars and light trucks
may vary with respect to these grades,
they must also conform to federal
safety requirements and additional
General Motors Tire Performance
Criteria (TPC) standards. Quality grades can be found where
applicable on the tire sidewall between
tread shoulder and maximum section
width. For example:
Treadwear 200 Traction AA Temperature A
All Passenger Car Tires Must Conform to
Federal Safety Requirements In Addition
To These Grades.
Treadwear
The treadwear grade is a comparative
rating based on the wear rate of the
tire when tested under controlled
conditions on a specified government
test course. For example, a tire graded
150 would wear one and one-half (1½)
times as well on the government course
as a tire graded 100. The relative
performance of tires depends upon the
actual conditions of their use, however,
and may depart significantly from the
norm due to variations in driving habits,
service practices and differences in road
characteristics and climate.