2010 CHEVROLET EXPRESS wiring

Adding Equipment to Your
Airbag-Equipped Vehicle
Q:Is there anything I might add to or change
about the vehicle that could keep the airbags
from working properly?
A:Yes. If you add things that change the vehicle’s
frame, bumper system, height, front end or side
sheet metal, they may keep the airbag system from
working properly. Changing or moving any parts
of the front seats, safety belts, the airbag sensing
and diagnostic module, steering wheel, instrument
panel, roof-rail airbag modules, ceiling headliner
or pillar garnish trim, front sensors, or airbag wiring
can affect the operation of the airbag system.
In addition, the vehicle may have a passenger
sensing system for the right front passenger
position, which includes sensors that are part of the
passenger seat. The passenger sensing system
may not operate properly if the original seat trim is
replaced with non-GM covers, upholstery or
trim, or with GM covers, upholstery or trim designed
for a different vehicle. Any object, such as an
aftermarket seat heater or a comfort enhancing pad
or device, installed under or on top of the seat
fabric, could also interfere with the operation of thepassenger sensing system. This could either
prevent proper deployment of the passenger
airbag(s) or prevent the passenger sensing system
from properly turning off the passenger airbag(s).
SeePassenger Sensing System on page 2-73.
If you have any questions about this, you should
contact Customer Assistance before you modify the
vehicle. The phone numbers and addresses for
Customer Assistance are in Step Two of the
Customer Satisfaction Procedure in this manual.
SeeCustomer Satisfaction Procedure on page 8-2.
If the vehicle has rollover roof-rail airbags, see
Different Size Tires and Wheels on page 6-80for
additional important information.
Q:Because I have a disability, I have to get my
vehicle modied. How can I nd out whether
this will affect my airbag system?
A:If you have questions, call Customer Assistance.
The phone numbers and addresses for Customer
Assistance are in Step Two of the Customer
Satisfaction Procedure in this manual. See
Customer Satisfaction Procedure on page 8-2.
In addition, your dealer/retailer and the service manual
have information about the location of the airbag sensors,
sensing and diagnostic module and airbag wiring.
2-79

This chime and light are
repeated if the passenger
remains unbuckled and
the vehicle is in motion.
If the passenger safety belt is buckled, neither the
chime nor the light comes on.
The front passenger safety belt warning light and chime
may turn on if an object is put on the seat such as a
briefcase, handbag, grocery bag, laptop or other
electronic device. To turn off the warning light and or
chime, remove the object from the seat or buckle
the safety belt.
Airbag Readiness Light
The system checks the airbag’s electrical system for
possible malfunctions. If the light stays on it indicates
there is an electrical problem. The system check
includes the airbag sensor, the pretensioners, the airbag
modules, the wiring and the crash sensing and
diagnostic module. For more information on the airbag
system, seeAirbag System on page 2-60.The airbag readiness light
flashes for a few seconds
when the engine is
started. If the light does
not come on then, have it
fixed immediately.
{WARNING:
If the airbag readiness light stays on after the
vehicle is started or comes on while driving, it
means the airbag system might not be working
properly. The airbags in the vehicle might not
inflate in a crash, or they could even inflate
without a crash. To help avoid injury, have the
vehicle serviced right away.
For vehicles with a remote start, the airbag readiness
light will stay on until the driver places the ignition switch
to the ON/RUN position.
If there is a problem with the airbag system, an airbag
Driver Information Center (DIC) message can also come
on. SeeDIC Warnings and Messages on page 4-44
for more information.
4-23

Audio System(s)
If the vehicle came without a radio, the wiring provisions
for a radio and an antenna were installed at the
assembly plant, so that if you want, a radio can be
installed at the dealer/retailer.
Determine which radio the vehicle has and read the
following pages to become familiar with its features.
{WARNING:
Taking your eyes off the road for extended periods
could cause a crash resulting in injury or death to
you or others. Do not give extended attention to
entertainment tasks while driving.
This system provides access to many audio and non
audio listings.
To minimize taking your eyes off the road while driving,
do the following while the vehicle is parked:
•Become familiar with the operation and controls of
the audio system.
•Set up the tone, speaker adjustments, and preset
radio stations.For more information, seeDefensive Driving on
page 5-2.
Notice:Contact your dealer/retailer before adding
any equipment.
Adding audio or communication equipment could
interfere with the operation of the vehicle’s engine,
radio, or other systems, and could damage them.
Follow federal rules covering mobile radio and
telephone equipment.
Notice:The chime signals related to safety belts,
parking brake, and other functions of your vehicle
operate through the radio/entertainment system.
If that equipment is replaced or additional equipment
is added to your vehicle, the chimes may not
work. Make sure that replacement or additional
equipment is compatible with your vehicle before
installing it. SeeAccessories and Modifications
on page 6-3.
The vehicle has Retained Accessory Power (RAP).
With RAP, the audio system can be played even after
the ignition is turned off. SeeRetained Accessory
Power (RAP) on page 3-23for more information.
4-59

Weight-Distributing Hitches and Weight
Carrying Hitches
A:Body to Ground Distance
B:Front of Vehicle
When using a weight-distributing hitch, the hitch must
be adjusted so the distance (A) remains the same both
before and after coupling the trailer to the tow vehicle.
If a step-bumper hitch will be used, the bumper could be
damaged in sharp turns. Make sure there is ample
room when turning to avoid contact between the trailer
and the bumper.If the loaded trailer being pulled will weigh more than
5,000 lbs (2 270 kg), be sure to use a properly mounted
weight-distributing hitch and sway control of the proper
size. This equipment is very important for proper vehicle
loading and good handling when driving. Always use a
sway control if the trailer will weigh more than these
limits. Ask a hitch dealer about sway controls.
Will any holes need to be made in the body of the
vehicle when a trailer hitch is installed?
If using the wiring provided with the factory-installed
trailering package, no holes need to be made in
the body of the vehicle. However, if an aftermarket hitch
is installed, holes may need to be made in the body.
If holes are made in the body, then be sure to seal the
holes later when the hitch is removed. If the holes
are not sealed, deadly carbon monoxide (CO) from the
engine’s exhaust can get into the vehicle as well as
dirt and water. See “Carbon Monoxide” underEngine
Exhaust on page 3-40.
Safety Chains
Always attach chains between the vehicle and the
trailer. Cross the safety chains under the tongue of the
trailer to help prevent the tongue from contacting
the road if it becomes separated from the hitch. Always
leave just enough slack so the rig can turn. Never
allow safety chains to drag on the ground.
5-37

Trailer Wiring Harness
The optional heavy-duty trailer wiring package includes
a wiring harness, with a seven-pin connector at the
rear of the vehicle and a four-wire harness assembly
under the driver side of the instrument panel. The
four-wire harness assembly comes without a connector.
If the vehicle does not have a trailer hitch, the
seven-wire harness assembly with connector is taped
together and located in a frame pocket at the driver side
rear left corner of the frame.
If the vehicle has a trailer hitch, the seven-wire harness
assembly with connector is attached to a bracket on
the hitch platform. In both cases, the seven-wire harness
has a connector and includes a 30-amp feed wire.
The seven-wire harness connector contains the following
trailer circuits:
•Light Green: Back-up Lamps (10A fuse)**
•White: Ground
•Dark Blue: Trailer Brake Signal
•Dark Green: Right Rear Stop and Turn Signal*
•Red/Black Stripe: Battery Feed (30A Fuse)
•Brown: Trailer Park Lamp Supply Voltage
(15A fuse)**
•Yellow: Left Rear Stop and Turn Signal *
The four-wire harness (without connector) contains the
following circuits:
•Black: Ground
•Red/White: Battery Feed
•Dark Blue: Trailer Brake Signal
•Light Blue: CHMSL/Stoplamp Supply Voltage
* If the vehicle is a cutaway with trailer provisions, a
15 amp fuse will be shared for both left/stop trailer turn
and right/stop trailer turn signals. However, the
cutaway lighting connector will have a 10 amp fuse for
each signal.
** If the vehicle is a cutaway with trailer provisions, a
15 amp fuse will be shared for trailer park lamps
and cutaway rear lighting connector park lamps. Also, a
10 amp fuse will be shared for trailer back-up lamps
and cutaway rear lighting connector back-up lamps.
5-42

Tires..............................................................6-60
Tire Sidewall Labeling...................................6-61
Tire Terminology and Definitions.....................6-65
Inflation - Tire Pressure.................................6-68
Dual Tire Operation.......................................6-70
Tire Pressure Monitor System.........................6-70
Tire Pressure Monitor Operation.....................6-72
Tire Inspection and Rotation...........................6-75
When It Is Time for New Tires.......................6-78
Buying New Tires.........................................6-79
Different Size Tires and Wheels......................6-80
Uniform Tire Quality Grading..........................6-81
Wheel Alignment and Tire Balance..................6-82
Wheel Replacement......................................6-82
Tire Chains..................................................6-84
If a Tire Goes Flat........................................6-85
Changing a Flat Tire.....................................6-86
Removing the Spare Tire and Tools................6-87
Removing the Flat Tire and Installing the
Spare Tire................................................6-90
Secondary Latch System...............................6-97
Storing a Flat or Spare Tire and Tools...........6-100
Spare Tire.................................................6-101
Appearance Care..........................................6-102
Interior Cleaning.........................................6-102
Fabric/Carpet..............................................6-103Instrument Panel, Vinyl, and Other Plastic
Surfaces.................................................6-104
Care of Safety Belts....................................6-104
Weatherstrips.............................................6-105
Washing Your Vehicle..................................6-105
Cleaning Exterior Lamps/Lenses....................6-105
Finish Care................................................6-106
Windshield and Wiper Blades.......................6-106
Aluminum Wheels.......................................6-107
Tires.........................................................6-107
Sheet Metal Damage...................................6-107
Finish Damage...........................................6-108
Underbody Maintenance...............................6-108
Chemical Paint Spotting...............................6-108
Vehicle Identication.....................................6-109
Vehicle Identification Number (VIN)................6-109
Service Parts Identification Label...................6-109
Electrical System..........................................6-109
Add-On Electrical Equipment.........................6-109
Headlamp Wiring........................................6-110
Windshield Wiper Fuses...............................6-110
Fuses and Circuit Breakers..........................6-110
Floor Console Fuse Block............................6-111
Engine Compartment Fuse Block...................6-112
Capacities and Specications........................6-116
Section 6 Service and Appearance Care
6-2

The vehicle has an airbag system. Before attempting
to add anything electrical to the vehicle, seeServicing
Your Airbag-Equipped Vehicle on page 2-78andAdding
Equipment to Your Airbag-Equipped Vehicle on
page 2-79.
Headlamp Wiring
The headlamp wiring is protected by fuses in the engine
compartment fuse block. An electrical overload will cause
the lamps to flicker on and off, or in some cases to remain
off. If this happens, have your headlamp wiring checked
right away.
Windshield Wiper Fuses
The windshield wiper motor is protected by a circuit
breaker and a fuse. If the motor overheats due to heavy
snow, etc., the wiper will stop until the motor cools.Although the circuit is protected from electrical overload,
overload due to heavy snow, etc., 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 some electrical problem and not
snow, etc., 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 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.
6-110

Mini Fuse Usage
3 Right Stop/Turn Trailer
4 Spare
5 Spare
6 Fuel System Control Module Ignition
7 Body Control Module 5
8 Body Control Module 7
9 Body Control Module 4
10 Instrument Panel Cluster
11 Trailer Wiring
12 Spare
13 Brake Switch
14 Windshield Washer
16 Horn
17 Transmission
18 Air Conditioning Compressor
19 Engine Control Module Battery
20 Spare
21 Left Stop/Turn Trailer
22 Spare
23 Spare
24 Fuel Pump
25 Auxiliary Power Outlet
26 Body Control Module 3
6-113