2005 GMC ENVOY turn signal

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
Dark Blue: Electric Brakes
Red: Battery Feed (The chassis wiring ring terminal
must be fastened to a stud on the underhood
electrical center before the trailer feed will
become active.)
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 qualied service center.
4-68

Service............................................................5-3
Doing Your Own Service Work.........................5-4
Adding Equipment to the Outside
of Your Vehicle...........................................5-5
Fuel................................................................5-5
Gasoline Octane............................................5-5
Gasoline Specications....................................5-5
California Fuel...............................................5-5
Additives.......................................................5-6
Fuels in Foreign Countries...............................5-6
Filling Your Tank............................................5-7
Filling a Portable Fuel Container.......................5-9
Checking Things Under the Hood....................5-10
Hood Release..............................................5-10
Engine Compartment Overview.......................5-12
Engine Oil...................................................5-16
Engine Oil Life System..................................5-19
Engine Air Cleaner/Filter................................5-20
Automatic Transmission Fluid.........................5-22
Engine Coolant.............................................5-25
Radiator Pressure Cap..................................5-28
Engine Overheating.......................................5-28
Cooling System............................................5-30Engine Fan Noise.........................................5-35
Power Steering Fluid.....................................5-36
Windshield Washer Fluid................................5-36
Brakes........................................................5-37
Battery........................................................5-41
Jump Starting...............................................5-42
Rear Axle.......................................................5-47
Four-Wheel Drive............................................5-48
Front Axle......................................................5-48
Bulb Replacement..........................................5-49
Halogen Bulbs..............................................5-49
Headlamps, Front Turn Signal, Sidemarker,
and Parking Lamps....................................5-50
Taillamps, Turn Signal, and Stoplamps............5-50
Back-Up Lamps............................................5-51
Replacement Bulbs.......................................5-51
Windshield Wiper Blade Replacement..............5-52
Tires..............................................................5-54
Tire Sidewall Labelling...................................5-55
Tire Terminology and Denitions.....................5-58
Ination - Tire Pressure.................................5-61
Tire Inspection and Rotation...........................5-62
When It Is Time for New Tires.......................5-64
Section 5 Service and Appearance Care
5-1

Headlamps, Front Turn Signal,
Sidemarker, and Parking Lamps
To replace a headlamp, front turn signal/parking or
sidemarker bulb, do the following:
1. Open the hood.Hood Release on page 5-10for
more information.
2. Lift the inner quick release clips.
3. Pull the headlamp assembly away from the vehicle.
4. Remove the cover from the headlamp bulb.
5. Disconnect the wiring harness.
6. Remove the bulb that needs to be replaced by
turning the socket counterclockwise.
7. Replace the old bulb with a new one.
8. Reinstall by reversing Steps 1 through 6.
Taillamps, Turn Signal, and
Stoplamps
To replace a stoplamp/taillamp or turn signal bulb, do
the following:
1. Open the liftgate. SeeLiftgate/Liftglass on
page 2-13for more information.
2. Remove the two
screws from the
taillamp assembly.
3. Pull the assembly away from the vehicle.
5-50

4. Unclip the wiring harness (A) and remove the
three socket retaining screws (B).
5. Remove the socket by releasing the retaining tabs.
6. Holding the socket, pull the bulb to release it from
the socket.
7. Push the new bulb into the socket until it clicks.
8. Reinstall the socket and screws.
9. Reconnect the wiring harness.
10. Reinstall the taillamp assembly and tighten
the screws.
11. Close the liftgate.
Back-Up Lamps
The back-up lamps are located in the rear bumper.
To replace a bulb, do the following:
1. Reach behind the rear bumper and locate
the bulb socket.
2. Turn it counterclockwise to remove from the bulb
assembly.
3. Pull the bulb from the bulb socket.
4. Push in a new bulb into the bulb socket.
5. Reinstall the bulb socket by lining up the tabs in the
lamp assembly and turn it clockwise to secure it.
Replacement Bulbs
Exterior Lamp Bulb Number
Back-up Lamps 3157
Front Sidemarker Lamps 194
Front Turn Signal Lamps 3457
Halogen Headlamps
High-Beam 9005 HB3
Low-Beam 9006 HB4
Rear Turn Signal, Stoplamp and
Taillamp3057
For replacement bulbs not listed here, contact
your dealer.
5-51

Fuses Usage
37 Front Parking Lamps
38 Left Turn Signal
39Heat Ventilation Air
Conditioning 1
40 Truck Body Controller 4
41 Radio
42 Trailer Park
43 Right Turn Signal
44 Heat Ventilation Air ConditioningFuses Usage
45 Rear Fog Lamps
46 Auxiliary Power 1
47 Ignition 0
48 Four-Wheel Drive
49 Blank
50 Truck Body Controller Ignition
51 Brakes
52 Truck Body Controller Run
5-109

Fuses Usage
29 Rainsense™ Wipers
30 Parking Lamps
31 Truck Body Controller Accessory
32 Truck Body Controller 5
33 Front Wipers
34 Vehicle Stop
35 Transmission Control Module
36Heat Ventilation Air
Conditioning B
37 Front Parking Lamps
38 Left Turn Signal
39Heat Ventilation Air
Conditioning 1
40 Truck Body Controller 4
41 Radio
42 Trailer Park
43 Right Turn SignalFuses Usage
44 Heat Ventilation Air Conditioning
45 Rear Fog Lamps
46 Auxiliary Power 1
47 Ignition 0
48 Four-Wheel Drive
49 Blank
50 Truck Body Controller Ignition
51 Brakes
52 Truck Body Controller Run
BLANK Blank
BLANK Blank
BLANK Blank
BLANK Blank
BLANK Blank
BLANK Blank
5-112

Audio System(s) (cont.)
Care of Your CDs and DVDs.......................3-138
Chime Level Adjustment.............................3-139
Fixed Mast Antenna...................................3-139
Navigation/Radio System.............................3-134
Radio with Cassette and CD.........................3-93
Radio with CD....................................3-66, 3-77
Radio with Six-Disc CD..............................3-107
Rear Seat Audio (RSA)...............................3-134
Setting the Time..........................................3-65
Theft-Deterrent Feature...............................3-135
Understanding Radio Reception...................3-137
XM™ Satellite Radio Antenna System...........3-139
Automatic Headlamp System............................3-16
Automatic Transmission
Fluid..........................................................5-22
Operation...................................................2-23
B
Battery..........................................................5-41
Run-Down Protection...................................3-19
Before Leaving on a Long Trip.........................4-36
Brake
Anti-Lock Brake System (ABS)........................ 4-7
Emergencies................................................ 4-9
Parking......................................................2-30
System Warning Light..................................3-40
Brake Pedal, Throttle.......................................2-21Brakes..........................................................5-37
Braking........................................................... 4-6
Braking in Emergencies..................................... 4-9
Break-In, New Vehicle.....................................2-18
Bulb Replacement...........................................5-49
Back-Up Lamps...........................................5-51
Halogen Bulbs............................................5-49
Headlamps, Front Turn Signal, Sidemarker,
and Parking Lamps..................................5-50
Replacement Bulbs......................................5-51
Taillamps, Turn Signal, and Stoplamps............5-50
Buying New Tires...........................................5-64
C
California Fuel.................................................. 5-5
Canadian Owners................................................ ii
Capacities and Specications..........................5-113
Carbon Monoxide...................2-13, 2-34, 4-39, 4-56
Care of
Safety Belts................................................5-89
Your Cassette Tape Player..........................3-137
Your CD and DVD Player...........................3-139
Your CDs and DVDs..................................3-138
Cargo Cover..................................................2-59
Center Console Storage Area...........................2-54
Chains, Tire...................................................5-68
Charging System Light....................................3-38
2

Fuses
Engine Compartment Fuse Block...................5-97
Fuses and Circuit Breakers...........................5-97
Rear Underseat Fuse Block.........................5-106
Windshield Wiper.........................................5-96
G
Gage
Check Gages Warning Light..........................3-49
Engine Coolant Temperature.........................3-41
Fuel..........................................................3-50
Oil Pressure...............................................3-45
Speedometer..............................................3-34
Tachometer.................................................3-34
Voltmeter Gage...........................................3-39
Garage Door Opener.......................................2-49
Gasoline
Octane........................................................ 5-5
Specications............................................... 5-5
Gate Ajar Light...............................................3-49
Glove Box.....................................................2-54
GM Mobility Reimbursement Program.................. 7-6
H
Hazard Warning Flashers................................... 3-6
Head Restraints............................................... 1-5
Headlamps....................................................3-15
Automatic Headlamp System.........................3-16
Bulb Replacement.......................................5-49
Daytime Running Lamps...............................3-16
Electrical System.........................................5-96
Flash-to-Pass............................................... 3-8
Halogen Bulbs............................................5-49
Headlamps, Front Turn Signal, Sidemarker,
and Parking Lamps..................................5-50
High/Low Beam Changer................................ 3-8
On Reminder..............................................3-16
Washer......................................................3-11
Heated Seats................................................... 1-3
Heater...........................................................3-21
Heater...........................................................3-23
Highbeam On Light.........................................3-48
Highway Hypnosis...........................................4-37
Hill and Mountain Roads..................................4-37
HomeLink
®Transmitter....................................2-49
HomeLink®Transmitter, Programming................2-50
Hood
Checking Things Under................................5-10
Release.....................................................5-10
Horn............................................................... 3-6
How to Use This Manual...................................... ii
How to Wear Safety Belts Properly...................1-13
6