2008 CHEVROLET TAHOE wiring

Servicing Your Airbag-Equipped
Vehicle
Airbags affect how your vehicle should be serviced.
There are parts of the airbag system in several places
around your vehicle. Your dealer/retailer and the
service manual have information about servicing your
vehicle and the airbag system. To purchase a service
manual, seeService Publications Ordering Information
on page 7-16.
{CAUTION:
For up to 10 seconds after the ignition is
turned off and the battery is disconnected,
an airbag can still inate during improper
service. You can be injured if you are close
to an airbag when it inates. Avoid yellow
connectors. They are probably part of the
airbag system. Be sure to follow proper
service procedures, and make sure the person
performing work for you is qualied to do so.
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 your 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, overhead console, front sensors, side
impact sensors, rollover sensor module, or airbag
wiring can affect the operation of the airbag system.
In addition, your vehicle has a passenger sensing
system for the right front passenger’s position, which
includes sensors that are part of the passenger’s
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
1-90

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 the passenger
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 1-85.
If you have any questions about this, you should
contact Customer Assistance before you modify
your 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 7-2.
If your vehicle has rollover roof-rail airbags, see
Different Size Tires and Wheels on page 5-84
for additional important information.Q:What if I added a snow plow? Will it keep
the airbags from working properly?
A:We have designed our airbag systems to work
properly under a wide range of conditions, including
snow plowing with vehicles that have the optional
Snow Plow Prep Package (RPO VYU). But do
not change or defeat the snow plow’s “tripping
mechanism.” If you do, it can damage your snow
plow and your vehicle, and it may cause an
airbag ination.
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 7-2.
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.
1-91

When you want to open a rear door when the security
lock is on, do the following:
1. Unlock the door by lifting the rear door manual lock,
using the power door lock switch, or the Remote
Keyless Entry (RKE) transmitter, if the vehicle
has one.
2. Open the door from the outside.
To cancel the rear door security lock, do the following:
1. Unlock the door and open it from the outside.
2. Insert the key into the security lock slot and turn it
so the slot is in the vertical position.
Lockout Protection
This feature protects you from locking the key in the
vehicle when the key is in the ignition and a front door
is open.
If the driver’s side power door lock switch is pressed
when the driver’s door is open and the key is in
the ignition, all of the doors will lock and then the driver’s
door will unlock.
If the passenger’s side power door lock switch is
pressed when the front passenger’s door is open and
the key is in the ignition, all of the doors will lock
and then the front passenger’s door will unlock.
Liftgate/Liftglass
{CAUTION:
It can be dangerous to drive with the liftglass
or liftgate open because carbon monoxide
(CO) gas can come into your vehicle. You
cannot see or smell CO. It can cause
unconsciousness and even death.
If you must drive with the liftglass or liftgate
open, or if electrical wiring or other cable
connections must pass through the seal
between the body and the liftglass or liftgate:
Make sure all other windows are shut.
Turn the fan on your heating or cooling
system to its highest speed with the
recirculation mode off. That will force
outside air into your vehicle. SeeClimate
Control System on page 3-22orDual
Automatic Climate Control System on
page 3-24.
CAUTION: (Continued)
2-12

Both the liftglass and liftgate have an electric latch. If
the battery is disconnected or has low voltage, the
liftglass and liftgate will not open. The liftglass
and liftgate will resume operation when the battery is
reconnected and charged.
If the battery is properly connected and has adequate
voltage, and the liftgate or liftglass still will not function,
your vehicle should be taken to a dealership for
service.
Power Liftgate
Power Liftgate Operation
{CAUTION:
It can be dangerous to drive with the liftgate
open because carbon monoxide (CO) gas can
come into your vehicle. You cannot see or
smell CO. It can cause unconsciousness and
even death.
CAUTION: (Continued)
CAUTION: (Continued)
If you must drive with the liftgate open, or if
electrical wiring or other cable connections
must pass through the seal between the body
and the liftgate:
Make sure all other windows are shut.
Turn the fan on your heating or cooling
system to its highest speed with the
recirculation mode off. That will force
outside air into your vehicle. See Climate
Control System in the index.
If you have air outlets on or under the
instrument panel, open them all the way.
If your vehicle has a power liftgate, disable
the power liftgate function.
SeePower Liftgate on page 2-14.
On vehicles with a power liftgate the button is located
on the overhead console.
The vehicle must be in PARK (P) to use the power
liftgate feature.
&:Press the top of the button to open or close the
power liftgate.
2-14

Auxiliary Roof Mounted Lamp
If your vehicle has this feature, this button includes
wiring provisions for a dealer or a qualied service
center to install an auxiliary roof lamp.
This button is located on
the overhead console.
When the wiring is connected to an auxiliary roof
mounted lamp, pressing the bottom of the button will
activate the lamp and illuminate an indicator light at the
bottom of this button. Pressing the top of the button
will turn off the roof mounted lamp and indicator.
The emergency roof lamp circuit is fused at 30 amps,
so the total current draw of the attached lamps
should be less than this value. The attachment points
for the roof lamp circuits are two blunt cut wires located
above the overhead console, a dark green switched
power wire and a black ground wire.
For further information on roof mount emergency lamp
installation, please visit the GM Uptter website at
www.gmuptters.com or contact your dealer.If your vehicle has this button, your vehicle may have
the snow plow prep package. For further information see
Adding a Snow Plow or Similar Equipment on
page 4-41.
Instrument Panel Brightness
D(Instrument Panel Brightness):This feature
controls the brightness of the instrument panel lights
and is located next to the exterior lamp control.
Push the knob to extend out and then it can be turned.
Turn the knob clockwise or counterclockwise to
brighten or dim the instrument panel lights. Turning the
knob to the farthest clockwise position turns on the
dome lamps.
Dome Lamps
The dome lamps come on when any door is opened.
They turn off after all the doors are closed.
The dome lamps can also be turned on by turning the
instrument panel brightness knob, located next to
the exterior lamps control, clockwise to the farthest
position. In this position, the dome lamps remain
on whether a door is opened or closed.
3-18

The passenger safety belt light, located on the
instrument panel, will come on and stay on for
several seconds and then ash for several more.
This chime and light are
repeated if the passenger
remains unbuckled and
the vehicle is in motion.
If the passenger’s safety belt is buckled, neither the
chime nor the light will come on.
Airbag Readiness Light
There is an airbag readiness light on the instrument
panel cluster, which shows the airbag symbol. The
system checks the airbag’s electrical system for
malfunctions. The light tells you if 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 1-76.This light will come on
when you start your
vehicle, and it will ash
for a few seconds.
The light should go out
and the system is ready.
If the airbag readiness light stays on after you start
the vehicle or comes on when you are driving,
your airbag system may not work properly. Have your
vehicle serviced right away.
{CAUTION:
If the airbag readiness light stays on after you
start your vehicle, it means the airbag system
may not be working properly. The airbags in
your vehicle may not inate in a crash, or they
could even inate without a crash. To help
avoid injury to yourself or others, have your
vehicle serviced right away.
The airbag readiness light should ash for a
few seconds when you start the engine. If the light
does not come on then, have it xed immediately.
3-37

Keep in mind that reserve capacity numbers are
intended as a guide when selecting the amount of
equipment or cargo your vehicle can carry. If you are
unsure of your vehicle’s front, rear, or total weight, go to
a weigh station and weigh your vehicle. Your
dealer/retailer can also help you with this.
The total vehicle reserve capacity for your vehicle can
be found in the lower right corner of the Certication/Tire
label as shown previously.
See your dealer/retailer for additional advice and
information about using a snow plow on your vehicle.
Also, seeLoading the Vehicle on page 4-35.
Emergency Roof Lamp Provisions
Vehicles with the RPO VYU snow plow prep package
also have an emergency roof lamp provision package,
RPO TRW. Wiring for the emergency roof lamp is
provided above the overhead console. SeeAuxiliary
Roof Mounted Lamp on page 3-18for switch location.
Towing
Towing Your Vehicle
To avoid vehicle damage, a platform or atbed trailer
should be used to transport this vehicle. Consult
your dealer/retailer or a professional towing service if
you need to have your disabled vehicle towed. See
Roadside Assistance Program on page 7-8.
If you want to tow your vehicle behind another vehicle
for recreational purposes (such as behind a motorhome),
see “Recreational Vehicle Towing” following.
Recreational Vehicle Towing
Recreational vehicle towing means towing your vehicle
behind another vehicle – such as behind a motorhome.
The two most common types of recreational vehicle
towing are known as dinghy towing, towing your vehicle
with all four wheels on the ground, and dolly towing,
towing your vehicle with two wheels on the ground and
two wheels up on a device known as a “dolly”.
With the proper preparation and equipment, many
vehicles can be towed in these ways. See “Dinghy
Towing” and “Dolly Towing”, following.
4-45

Trailer Wiring Harness
Your vehicle is equipped with the following wiring
harnesses for towing a trailer.
Basic Trailer Wiring
The trailer wiring harness, with a seven-pin connector,
is located at the rear of the vehicle and is tied to
the vehicle’s frame. The harness connector can be
plugged into a seven-pin universal heavy-duty trailer
connector available through your dealer/retailer.
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/retailer or a qualied service center.
Heavy-Duty Trailer Wiring Harness
Package
Your vehicle is equipped with the seven-wire trailer
towing harness. This harness with a seven-pin universal
trailer connector is attached to a bracket on the hitch
platform.
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*
4-64