fuse GMC ENVOY 2001 User Guide

4-46
The compressor should operate for brief periods of time.
If the sound continues for an extended period of time,
your vehicle needs service. To keep your battery from
being drained, you may want to remove the LD LEV
fuse in the engine compartment fuse block until you
can get your vehicle serviced (see ªFuses and Circuit
Breakersº in the Index).
Using heavier suspension components to get added
durability might not change your weight ratings. Ask
your dealer to help you load your vehicle the right way.
Add-On Equipment
When you carry removable items, you may need to put a
limit on how many people you carry inside your vehicle.
Be sure to weigh your vehicle before you buy and install
the new equipment.
NOTICE:
Your warranty doesn't cover parts or components
that fail because of overloading.
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.
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4-58 Trailer Wiring Harness
The light-duty trailer wiring is a six-wire harness
assembly. The optional heavy
-duty trailer wiring is an
eight
-wire harness assembly. The harnesses are stored
under the vehicle, along the passenger
-side frame
crossmember on two
-door vehicles or on the driver's
side corner frame rear crossmember on four
-door
vehicles. The heavy
-duty trailer wiring is fused in the
engine compartment fuse block. See ªFuses and Circuit
Breakersº in the Index. Both harnesses have no
connector and should be wired by a qualified
electrical technician. The technician can use the
following color code chart when connecting the
wiring harness to your trailer.
Dark Blue: Use for electric trailer brakes or auxiliary
wiring (eight
-wire harness only).

Red: Use for battery charging; it connects to the
starter solenoid (eight
-wire harness only).

Light Green: Back
-up lamps.

Brown: Taillamps and parking lamps.

Yellow: Left stoplamp and turn signal.

Dark Green: Right stoplamp and turn signal.

White: Ground wire.

Light Blue: Auxiliary stoplamp.
Securely attach the harness to the trailer, then tape or
strap it to your vehicle's frame rail. Be sure you leave it
loose enough so the wiring doesn't bend or break,
but not so loose that it drags on the ground. Store the
harness in its original place. Wrap the harness together
and tie it neatly so it won't be damaged.
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6-3
CAUTION:
You can be injured and your vehicle could be
damaged if you try to do service work on a
vehicle without knowing enough about it.

Be sure you have sufficient knowledge,
experience, the proper replacement parts
and tools before you attempt any vehicle
maintenance task.

Be sure to use the proper nuts, bolts and
other fasteners. ªEnglishº and ªmetricº
fasteners can be easily confused. If you use
the wrong fasteners, parts can later break
or fall off. You could be hurt.
Adding Equipment to the Outside of
Your Vehicle
Things you might add to the outside of your vehicle can
affect the airflow around it. This may cause wind noise
and affect windshield washer performance. Check with
your dealer before adding equipment to the outside of
your vehicle.
Fuel
Use regular unleaded gasoline rated at 87 octane or
higher. It is recommended that the gasoline meet
specifications which were developed by the American
Automobile Manufacturers Association (AAMA) and
endorsed by the Canadian Motor Vehicle Manufacturers
Association for better vehicle performance and engine
protection. Gasolines meeting the AAMA specification
could provide improved driveability and emission control
system performance compared to other gasolines.
In Canada, look for the
ªAuto Makers' Choiceº
label on the fuel pump.
Canada Only
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6-10 Engine Compartment Overview
When you lift the hood, you'll see these items:
A. Battery
B. Coolant Recovery Tank
C. Engine Oil Dipstick
D. Engine Oil FillE. Automatic
Transmission Dipstick
F. Power Steering Reservoir
G. Brake Master CylinderH. Engine Air Cleaner/Filter
I. Fuse Block
J. Windshield Washer
Fluid Reservoir
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6-63
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.
Headlamps
The headlamp wiring is protected by an internal circuit
breaker. 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 Wipers
The windshield wiper motor is protected by a circuit breaker
and a fuse. If the motor overheats due to heavy snow or ice,
the wiper will stop until the motor cools. If the overload is
caused by some electrical problem, be sure to get it fixed.
Power Windows and Other Power Options
Circuit breakers 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.
Fuses and Circuit Breakers
The wiring circuits in your 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.
If you ever have a problem on the road and don't have
a spare fuse, you can borrow one that has the same
amperage. Just pick some feature of your vehicle that
you can get along without
-- like the radio or cigarette
lighter
-- and use its fuse, if it is the correct amperage.
Replace it as soon as you can.
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6-64 Instrument Panel Fuse Block
The instrument panel fuse
block is located at the
driver's end of the
instrument panel.
Remove the cover by turning the fastener
counterclockwise. Extra fuses and the fuse extractor are
provided in the cover. To reinstall the fuse panel cover,
push in and turn the fastener clockwise.
Fuse/Circuit
BreakerUsage
A Not Used
B Not Used
1 Not Used
2 Cigarette Lighter,
Data Link Connector
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6-65
Fuse/Circuit
BreakerUsage
3 Cruise Control Module and
Switch, Body Control Module,
Heated Seats
4 Gages, Body Control Module,
Instrument Panel Cluster
5 Parking Lamps, Power Window
Switch, Body Control Module,
Ashtray Lamp
6 Steering Wheel Radio Controls
7 Headlamps Switch, Body Control
Module, Headlamp Relay
8 Courtesy Lamps, Battery
Run
-Down Protection
9 HVAC Control Head (Manual)
10 Turn Signal
11 Cluster, Engine Control Module
12 Interior LightsFuse/Circuit
BreakerUsage
13 Auxiliary Power
14 Power Locks Motor
15 4WD Switch, Engine Controls
(VCM, PCM, Transmission)
16 Supplemental Inflatable Restraint
17 Front Wiper
18 Steering Wheel Radio Controls
19 Radio, Battery
20 Amplifier
21 HVAC (Manual),
HVAC I (Automatic),
HVAC Sensors (Automatic)
22 Anti
-Lock Brakes
23 Rear Wiper
24 Radio, Ignition
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6-66 Engine Compartment Fuse Block
The fuse block is located under the hood at the
driver's side of the engine compartment. See ªEngine
Compartment Overviewº in the Index for more
information on location. Before using this fuse block
picture and chart, check to see that it matches the fuse
block in your vehicle. If the fuse block pictured here is
different than your vehicle's, use the fuse block picture
and chart located later in this section.
Remove the cover by turning the fastener
counterclockwise. To reinstall the fuse panel cover,
push in and turn the fastener clockwise.
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6-67
Name Usage
TRL TRN Trailer Left Turn
TRR TRN Trailer Right Turn
TRL B/U Trailer Back Up Lamps
VEH B/U Vehicle Back Up Lamps
RT TURN Right Turn Signal Front
LT TURN Left Turn Signal Front
HDLP W/W Not UsedName Usage
LT TRN Left Turn Signal Rear
RT TRN Right Turn Signal Rear
RR PRK Right Rear Parking Lamps
TRL PRK Trailer Park Lamps
LTHDLP Left Headlamp
RTHDLP Right Headlamp
FRPRK Front Parking Lamps
INT BAT I/P Fuse Block Feed
ENG I Engine Sensors/Solenoids, MAF,
CAM, PURGE, VENT
ECM B Engine Control Module, Fuel
Pump Module, Oil Pressure
ABS Anti
-Lock Brake System
ECM I Engine Control Module Injectors
A/C Air Conditioning
W/W PMP Not Used
HORN Horn
BTSI Automatic Transmission Shift
Lock Control System
B/U LP Back Up Lamps
IGN B Column Feed, IGN 2, 3, 4
RAP Retained Accessory Power
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6-69 Engine Compartment Fuse Block
(Vehicles with HID Headlamps)
The fuse block is located under the hood at the driver's
side of the engine compartment. See ªEngine
Compartment Overviewº in the Index for more
information on location. Before using this fuse block
picture and chart, check to see that it matches the fuse
block in your vehicle. If the fuse block pictured here is
different than your vehicle's, use the fuse block picture
and chart located earlier in this section.
Remove the cover by turning the fastener
counterclockwise. To reinstall the fuse panel cover,
push in and turn the fastener clockwise.
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