Page 205 of 388

4-27
CAUTION:
Snow can trap exhaust gases under your vehicle.
This can cause deadly CO (carbon monoxide) gas
to get inside. CO could overcome you and kill
you. You can't see it or smell it, so you might not
know it is in your vehicle. Clear away snow from
around the base of your vehicle, especially any
that is blocking your exhaust pipe. And check
around again from time to time to be sure snow
doesn't collect there.
Open a window just a little on the side of the
vehicle that's away from the wind. This will help
keep CO out.
Run your engine only as long as you must. This saves
fuel. When you run the engine, make it go a little faster
than just idle. That is, push the accelerator slightly. This
uses less fuel for the heat that you get and it keeps the
battery charged. You will need a well
-charged battery to
restart the vehicle, and possibly for signaling later on
with your headlamps. Let the heater run for a while.Then, shut the engine off and close the window almost
all the way to preserve the heat. Start the engine again
and repeat this only when you feel really uncomfortable
from the cold. But do it as little as possible. Preserve the
fuel as long as you can. To help keep warm, you can get
out of the vehicle and do some fairly vigorous exercises
every half hour or so until help comes.
Recreational Vehicle Towing
Your vehicle was not designed to be towed with all four
wheels on the ground. And, if your vehicle has all
-wheel
drive, it was not designed to be towed with only two
wheels on the ground. If your vehicle must be towed,
see ªTowing Your Vehicleº in the Index.
NOTICE:
Towing your vehicle with all four wheels on the
ground will damage drivetrain components. And,
if your vehicle has all
-wheel drive, towing with
only two wheels on the ground will also damage
drivetrain components.
Page 289 of 388
6-37 Headlamps
Sealed Beam Lamps
1. Remove the four retainer
screws and the retainer.
2. Pull the connector out
and unplug the lamp.
3. Plug the new lamp into the connector.
4. Reverse Steps 1 and 2 to reinstall the headlamp.
Page 290 of 388
6-38
Composite Headlamps
1. Open the hood.
2. Remove the two screws
from the sidemarker/turn
signal lamp.
3. Completely remove the sidemarker/turn signal lamp
by pulling out the assembly and disconnecting the
sidemarker/turn signal lamp sockets from the lamp.
Page 301 of 388

6-49 Wheel Alignment and Tire Balance
The wheels on your vehicle were aligned and balanced
carefully at the factory to give you the longest tire life
and best overall performance.
Scheduled wheel alignment and wheel balancing are not
needed. However, if you notice unusual tire wear or
your vehicle pulling one way or the other, the alignment
may need to be reset. If you notice your vehicle
vibrating when driving on a smooth road, your wheels
may need to be rebalanced.
Wheel Replacement
Replace any wheel that is bent, cracked, or badly rusted
or corroded. If wheel nuts keep coming loose, the wheel,
wheel bolts and wheel nuts should be replaced. If the
wheel leaks air, replace it (except some aluminum
wheels, which can sometimes be repaired). See your
dealer if any of these conditions exist.
Your dealer will know the kind of wheel you need.
Each new wheel should have the same load
-carrying
capacity, diameter, width, offset and be mounted the
same way as the one it replaces.
If you need to replace any of your wheels, wheel bolts
or wheel nuts, replace them only with new GM original
equipment parts. This way, you will be sure to have the
right wheel, wheel bolts and wheel nuts for your vehicle.
CAUTION:
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.
See ªChanging a Flat Tireº in the Index for
more information.
Page 312 of 388

6-60
Electrical System
Add-On Electrical Equipment
NOTICE:
Don't add anything electrical to your vehicle
unless you check with your dealer first. Some
electrical equipment can damage your vehicle
and the damage wouldn't be covered by your
warranty. Some add
-on electrical equipment
can keep other components from working as
they should.
Your vehicle has an air bag system. Before attempting to
add anything electrical to your vehicle, see ªServicing
Your Air Bag
-Equipped Vehicleº in the Index.
Headlamp Wiring
The headlamp wiring is protected by a circuit breaker in
the lamp switch. An electrical overload will cause the
lamps to go 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. If
the overload is caused by some electrical problem and
not snow, etc., be sure to get it fixed.
Power Windows and Other Power Options
Circuit breakers in the fuse panel protect the power
windows and other power accessories. When the current
load is too heavy, the circuit breaker opens and closes,
protecting the circuit until the problem is fixed or
goes away.
Page 315 of 388

6-63
Fuse/Circuit
BreakerUsage
4 DRL Relay, Instrument
Panel Cluster
5 Rear Defogger
6 Cruise Module, TBC Module,
Instrument Panel Cluster,
Cruise Control Switch,
Electrochromic Mirror
7 Power Outlets, DLC,
Subwoofer Amplifier
8 Crank Circuit Fuse, Park/Neutral
Switch, Starter Enable Relay
9 License Plate Lamp, Taillamps,
Parking Lamps, Ashtray Lamp,
Panel Lights, Trailer Taillamps,
Front and Rear Sidemarker
Lamps, Door Switch Illumination,
Headlamp Switch Illumination,
Rear Seat Audio Illumination,
TBC Module
10 Air Bag System
11 Not UsedFuse/Circuit
BreakerUsage
12 L, M1, M2 Blower Motor, Rear
A/C Relay Coil, Front Cont.
Temp. Door Motor, HI Blower
Relay, Defogger Timer Coil
13 Cigarette Lighter, Door
Lock Switches, Dutch Door
Release Module
14 Cluster Illum, HVAC Controls,
Chime Module, Radio
Illumination, Rear Heat Switch
Illumination, Rear Wiper/Washer
Switch Illumination, Rear Liftgate
Switch Illumination, Remote
Cassette Illumination, O/H
Console, TBC Illumination
15 TBC Module, Headlamp Relay
16 Front Turn Signals, Rear Turn
Signals, Trailer Turn Signals,
Back
-Up Lamps, BTSI Solenoid
17 Front Wipers, Front Washer Pump
18 VCM
-Ign 3, VCM-Brake,
Cruise Stepper Motor Signal,
ATC Module
Page 317 of 388
6-65
Feed Usage
AUX B Upfitter Battery Feed
AUX A Upfitter Accessory FeedRelay Usage
A/C Relay Rear Heat and Air Conditioning
Upfitter
-ACCY
RelayUpfitter Accessory
Starter
Enable RelayStarter
A/C
Enable RelayAir Conditioning
Headlamps
RelayHeadlamps
Fuel Pump Relay Fuel Pump
Fuse/Circuit
BreakerUsage
UPFITTER
-
BATTUpfitter Battery Power Stud,
Trailer Wiring Harness
UPFITTER
-
ACCYUpfitter Accessory Relay
Spare Not used
Spare Not used
Spare Not used
ECM
-1B Fuel Pump Relay and Motor,
VCM, Oil Pressure Switch/Sender
Page 318 of 388
6-66
Fuse/Circuit
BreakerUsage
HORN Horn Relay and Horn
A/C COMP A/C Enable Relay and Compressor
RR HTR/AC Rear Heater and A/C
ATC Active Transfer Case
-L Van
FRT HVAC Front Heater and A/C
ENG
-I Oxygen Sensors, Camshaft
Position Sensor, Mass Air Flow
Sensor, Evaporative Emission
Canister Vent Solenoid
IGN
-E A/C Enable Relay Coil
ECM
-I Fuel Injectors 1-6, Crankshaft
Position Sensor, VCM, Coil
Driver Module (EST),
Ignition Coil
Blank Not Used
RH HDLMP Right Headlamp
LH Headlamp Left HeadlampFuse/Circuit
BreakerUsage
Blank Not Used
Blank Not Used
DIODE
-1 A/C
Blank Not Used
Blank Not Used
Blank Not Used
LIGHTING Courtesy Fuse, Pwr. Adj. Mirrors
Fuse, TBC
-Battery Fuse
BATT Power ACCY CB, Stop/Hazard
Fuse, Auxiliary Power Fuse,
Cigarette Lighter Fuse, Radio
Battery Fuse
IGN A Starter Relay, Ignition Switch
IGN B Ignition Switch
ABS Electronic Brake Control Module
Blank Not Used
RAP Radio Accy, Power Windows
HTD MIR/RR
DEFOGRear Window Defogger, HVAC
Control Head