2003 GMC ENVOY brake light

Indicator Light
The indicator light on the in¯ator switch in the rear
passenger compartment also serves as an indicator for
internal system error. If the indicator light is ¯ashing
without the load leveling function or the in¯ator being
active, turn off the ignition. The next day turn on
the ignition and check the indicator light. The vehicle
can be driven with the light ¯ashing, but if it is you
should have the vehicle serviced as soon as possible.
Adding a Snow Plow or Similar
Equipment
Your vehicle was neither designed nor intended for a
snow plow.
Notice:Adding a snow plow or similar equipment
to your vehicle can damage it, and the repairs
wouldn't be covered by warranty. Do not install a
snow plow or similar equipment on your vehicle.
Towing a Trailer
{CAUTION:
If you don't use the correct equipment and
drive properly, you can lose control when you
pull a trailer. For example, if the trailer is too
heavy, the brakes may not work well -- or even
at all. You and your passengers could be
seriously injured. Pull a trailer only if you have
followed all the steps in this section. Ask your
dealer for advice and information about towing
a trailer with your vehicle.
Notice:Pulling a trailer improperly can damage
your vehicle and result in costly repairs not covered
by your warranty. To pull a trailer correctly, follow
the advice in this part, and see your dealer for
important information about towing a trailer with
your vehicle. Additional rear axle maintenance
is required for a vehicle used to tow a trailer. See
ªScheduled Maintenance Servicesº in the Index.
To identify the trailering capacity of your vehicle,
you should read the information in ªWeight of the Trailerº
that appears later in this section.
4-50

Trailer Wiring Harness
Your vehicle may be equipped with the seven-wire
trailer towing harness. This harness has a seven-pin
universal heavy-duty trailer connector that 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: Running Lamps
·White: Ground
·Light Green: Back-up Lamps
·Red: Battery Feed
·Dark Blue: Electric Brakes
If you need to tow a light-duty trailer with a standard
four-way round pin connector, an adapter connector is
available from your dealer.
Your vehicle may also be equipped with wiring for an
electric trailer brake controller. These wires are located
inside the vehicle on the driver's side under the
instrument panel. These wires should be connected to
an electric trailer brake controller by your dealer or
a quali®ed service center.
4-60

Brake Wear
Your vehicle has four-wheel disc brakes.
Disc brake pads have built-in wear indicators that make
a high-pitched warning sound when the brake pads
are worn and new pads are needed. The sound
may come and go or be heard all the time your vehicle
is moving (except when you are pushing on the
brake pedal ®rmly).
{CAUTION:
The brake wear warning sound means that
soon your brakes won't work well. That could
lead to an accident. When you hear the brake
wear warning sound, have your vehicle
serviced.
Notice:Continuing to drive with worn-out brake
pads could result in costly brake repair.Some driving conditions or climates may cause a brake
squeal when the brakes are ®rst applied or lightly
applied. This does not mean something is wrong with
your brakes.
Properly torqued wheel nuts are necessary to help
prevent brake pulsation. When tires are rotated, inspect
brake pads for wear and evenly tighten wheel nuts in
the proper sequence to GM torque speci®cations.
Brake linings should always be replaced as complete
axle sets.
See
Brake System Inspection on page 6-17.
Brake Pedal Travel
See your dealer if the brake pedal does not return to
normal height, or if there is a rapid increase in
pedal travel. This could be a sign of brake trouble.
Brake Adjustment
Every time you make a brake stop, your disc brakes
adjust for wear.
5-40

Notice:Ignoring these steps could result in costly
damage to your vehicle that wouldn't be covered
by your warranty.
Trying to start your vehicle by pushing or pulling it
won't work, and it could damage your vehicle.
1. Check the other vehicle. It must have a 12-volt
battery with a negative ground system.
Notice:If the other system isn't a 12-volt system
with a negative ground, both vehicles can be
damaged.
2. Get the vehicles close enough so the jumper cables
can reach, but be sure the vehicles aren't touching
each other. If they are, it could cause a ground
connection you don't want. You wouldn't be able to
start your vehicle, and the bad grounding could
damage the electrical systems.
To avoid the possibility of the vehicles rolling, set
the parking brake ®rmly on both vehicles involved in
the jump start procedure. Put an automatic
transmission in PARK (P) or a manual transmission
in NEUTRAL before setting the parking brake. If
you have a four-wheel-drive vehicle, be sure
the transfer case is not in NEUTRAL.
Notice:If you leave your radio on, it could be badly
damaged. The repairs wouldn't be covered by
your warranty.
3. Turn off the ignition on both vehicles. Unplug
unnecessary accessories plugged into the cigarette
lighter or accessory power outlets (if equipped).
Turn off the radio and all lamps that aren't needed.
This will avoid sparks and help to save both
batteries. And it could save your radio!
4. Open both hoods and locate the batteries. Find the
positive (+) and negative (-) terminals on each
battery. Your vehicle has a remote negative (-) jump
starting terminal. You should always use this
remote terminal instead of the terminal on the
battery. The remote negative (-) terminal is located
on the front engine lift bracket on vehicles with
the L6 engine or the engine accessory drive bracket
for vehicles with the V8 engine, and is marked
ªGND.º See
Engine Compartment Overview
on page 5-12for more information on location.
5-43

Fuses Usage
1Electrically-Controlled Air
Suspension
2Passenger's Side High-Beam
Headlamp
3Passenger's Side Low-Beam
Headlamp
4 Back-Up-Trailer Lamps
5 Driver's Side High-Beam Headlamp
6 Driver's Side Low-Beam Headlamp
7 Wash
8 Automatic Transfer Case
9 Windshield Wipers
10 Powertrain Control Module B
11 Fog Lamps
12 Stop Lamp
13 Cigarette Lighter
14 Ignition Coils
15 Air Suspension Ride
16 TBD-Ignition 1Fuses Usage
17 Crank
18 Air Bag
19 Electric Brake
20 Cooling Fan
21 Horn
22 Ignition E
23 Electronic Throttle Control
24Instrument Panel Cluster, Driver
Information Center
25 Automatic Shift Lock Control System
26 Engine 1
27 Back-Up
28 Powertrain Control Module 1
29 Oxygen Sensor
30 Air Conditioning
31 Truck Body Controller
32 Trailer
33 Anti-Lock Brakes (ABS)
5-93

Fuses Usage
1Electrically-Controlled Air
Suspension
2Passenger's Side High-Beam
Headlamp
3Passenger's Side Low-Beam
Headlamp
4 Back-Up-Trailer Lamps
5 Driver's Side High-Beam Headlamp
6 Driver's Side Low-Beam Headlamp
7 Wash
8 Automatic Transfer Case
9 Windshield Wipers
10 Powertrain Control Module B
11 Fog Lamps
12 Stop Lamp
13 Cigarette Lighter
14 Ignition Coils
15 Cannister Vent
16 TBD-Ignition 1
17 Crank
18 Air Bag
19 Electric Brake
20 Cooling Fan
21 HornFuses Usage
22 Ignition E
23 Electronic Throttle Control
24Instrument Panel Cluster, Driver
Information Center
25 Automatic Shift Lock Control System
26 Engine 1
27 Back-Up
28 Powertrain Control Module 1
30 Air Conditioning
31 Truck Body Controller 1
32 Trailer
33 Anti-Lock Brakes (ABS)
34 Ignition A
35 Blower Motor
36 Ignition B
50 Passenger's Side Trailer Turn
51 Driver's Side Trailer Turn
52 Hazard Flashers
53 Oxygen Sensor Bank A
54 Oxygen Sensor Bank B
55 Injector Bank A
56 Injector Bank B
Relays Usage
37 Headlamp Washer
5-96

Scheduled Maintenance
The services shown in this schedule up to 100,000 miles
(166 000 km) should be repeated after 100,000 miles
(166 000 km) at the same intervals for the life of
this vehicle. The services shown at 150,000 miles
(240 000 km) should be repeated at the same interval
after 150,000 miles (240 000 km) for the life of this
vehicle.
See
Part B: Owner Checks and Services on page 6-11andPart C: Periodic MaintenanceInspections on
page 6-16.
Footnotes
²The U.S. Environmental Protection Agency or the
California Air Resources Board has determined that the
failure to perform this maintenance item will not nullify
the emission warranty or limit recall liability prior to
the completion of the vehicle's useful life. We, however,
urge that all recommended maintenance services be
performed at the indicated intervals and the
maintenance be recorded.
+A good time to check your brakes is during tire
rotation. See Brake System Inspection on page 6-17.
Engine Oil Scheduled Maintenance
Change engine oil and ®lter as indicated by the GM
Oil Life System (or every 12 months, whichever
occurs ®rst). Reset the system.
Your vehicle has a computer system that lets you know
when to change the engine oil and ®lter. This is
based on engine revolutions and engine temperature,
and not on mileage. Based on driving conditions,
the mileage at which an oil change will be indicated can
vary considerably. For the oil life system to work
properly, you must reset the system every time the oil is
changed.
When the system has calculated that oil life has been
diminished, it will indicate that an oil change is
necessary. A CHANGE ENGINE OIL light will come on.
Change your oil as soon as possible within the next
two times you stop for fuel. It is possible that, if you are
driving under the best conditions, the oil life system
may not indicate that an oil change is necessary for over
a year. However, your engine oil and ®lter must be
changed at least once a year and at this time the system
must be reset. Your dealer has GM-trained service
people who will perform this work using genuine GM
parts and reset the system.
It is also important to check your oil regularly and keep
it at the proper level.
6-5

A
Accessory In¯ator...........................................5-62
Accessory Power Outlets.................................3-19
Adding a Snow Plow or Similar Equipment.........4-50
Adding Washer Fluid.......................................5-37
Additional Program Information........................... 7-8
Additives, Fuel................................................. 5-6
Add-On Electrical Equipment............................5-89
Adjusting the Speakers
(Balance/Fade)............................3-66, 3-74, 3-83
After Off-Road Driving.....................................4-28
Air Bag Systems.............................................1-51
How Does an Air Bag Restrain?....................1-58
Servicing Your Air Bag-Equipped Vehicle.........1-60
What Makes an Air Bag In¯ate?....................1-57
What Will You See After an
Air Bag In¯ates?......................................1-58
When Should an Air Bag In¯ate?...................1-56
Where Are the Air Bags?..............................1-54
Air Bag .........................................................3-37
Readiness Light..........................................3-37
Air Cleaner/Filter, Engine.................................5-20
All Overseas Locations...................................... 7-4
AM .............................................................3-105
Antenna, Fixed Mast......................................3-107
Anti-Lock Brake, System Warning Light..............3-41
Anti-lock Brake System..................................... 4-6
Appearance Care............................................5-80
Care of Safety Belts....................................5-83Appearance Care (cont.)
Chemical Paint Spotting...............................5-86
Cleaning the Inside of Your Vehicle................5-80
Cleaning the Outside of Your Vehicle..............5-83
Finish Damage............................................5-86
Sheet Metal Damage...................................5-85
Underbody Maintenance...............................5-86
Vehicle Care/Appearance Materials................5-86
Weatherstrips..............................................5-83
Approaching a Hill..........................................4-20
Ashtrays........................................................3-20
Audio Speakers..............................................3-94
Audio System(s).............................................3-63
Audio Steering Wheel Controls....................3-105
Care of Your Cassette Tape Player...............3-106
Care of Your CD and DVD Player................3-107
Care of Your CDs and DVDs.......................3-107
Chime Level Adjustment.............................3-107
Fixed Mast Antenna...................................3-107
Audio Systems..............................................3-104
Radio Personalization.................................3-104
Audio System(s).............................................3-71
Radio with Cassette and CD.........................3-71
Radio with CD............................................3-64
Radio with Six-Disc CD................................3-81
Rear Seat Audio (RSA)...............................3-103
Setting the Time..........................................3-63
Theft-Deterrent Feature...............................3-104
Understanding Radio Reception...................3-105
Automatic Headlamp System............................3-15
1