1998 GMC ENVOY wiring

Resynchronization Resynchronization may be necessary due to the security
method used by this system. The transmitter does not
send the
same signal twice to the receiver. The receiver
will
not respond to a signal it has been sent previously.
This prevents anyone
from recording and playing back
the signal from the transmitter.
To resynchronize your transmitter, stand close to your
vehicle and press and hold the LOCK and UNLOCK
buttons on the transmitter at the same time for seven
seconds. The door locks should cycle to confirm
synchronization.
If the locks do not cycle. see your
dealer for service.
LiftgateLiftglass
It can be dangerous to drive with the liftgate or
liftglass open because carbon monoxide (CO) gas
can come into your vehicle. You can’t see or smell
CO. It can cause unconsciousness and even death.
If‘ you must drive with the liftgate or liftglass
open or if electrical wiring or other cable
connections must pass through the seal between
the body and the liftgate
or liftglass:
Make sure all windows are shut.
Turn the fan on your heating or cooling
system to its highest speed with the setting
on any airflow selection except
RECIRCULATION. That will force outside
air into your vehicle. See “Comfort
Controls” in the Index.
If you have air outlets on or under the
instrument panel, open them
all the way.
See “Engine Exhaust” in the Index.
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Air Bag Readiness Light
There is an air bag readiness light on the instrument
panel, which shows
the air bag symbol. The system
checks the air bag’s electrical system for malfunctions.
The light tells you
if there is an electrical problem. The
system check includes
the air bag sensors, the air bag
module, the wiring and the diagnostic module. For more
information
on the air bag system, see “Air Bag” in
the Index.
This light will come on
when you start your engine,
and
it will flash for a few
seconds. Then the light
should go out. This means
the system is ready.
If the air bag readiness light stays on after you start the
engine or comes on when you are driving, your air bag
system may
not work properly. Have your vehicle
serviced right away.
The air bag readiness light should flash for a few
seconds when
you turn the ignition key to RUN. If the
light doesn’t come
on then, have it fixed so it will be
ready to warn
you if there is a problem.
Charging System Indicator Light
The charging system light
will come on briefly when
you turn on the ignition, but
’ the engine is not running,
as a check to show you it
is working.
It should go out once the engine
is running. If it stays
on, or comes on while you are driving, you may have a
problem with the charging system.
It could indicate that
you have problems with
a generator drive belt, or
another electrical problem. Have
it checked right away.
Driving while this light
is on could drain your battery.
If you must drive a short distance with the light on, be
certain to turn off all your accessories, such as the radio
and air conditioner.
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Passing
You’ll need more passing distance up ahead when
you’re towing a trailer. And, because you’re
a good deal
longer,
you’ll need to go much farther beyond the
passed vehicle before you can return to your lane.
Backing Up
Hold the bottom of the steering wheel with one hand.
Then,
to move the trailer to the left, just move that hand
to the left. To move the trailer to the right, move your
hand to the right. Always back up slowly and,
if
possible, have someone guide you.
Making Turns
NOTICE:
~~
Making very sharp turns while trailering could
cause the trailer to come in contact with the
vehicle. Your vehicle could be damaged. Avoid
making very sharp turns while trailering.
When you’re turning with a trailer, make wider turns than
normal.
Do this so your trailer won’t strike soft shoulders,
curbs, road signs, trees or other objects.
Avoid jerky or
sudden maneuvers. Signal well
in advance.
Turn Signals When Towing a Trailer
When you tow a trailer, your vehicle has to have extra
wiring and a heavy-duty turn signal flasher.
The arrows on your instrument panel will flash
whenever you signal a
turn or lane change. Properly
hooked up,
the trailer lamps will also flash, telling other
drivers you’re about to
turn, change lanes or stop.
When towing a trailer, the arrows
on your instrument
panel will flash for turns even
if the bulbs on the trailer
are burned out. Thus, you may think drivers behind you
are seeing your signal when
they are not. It’s important
to check occasionally
to be sure the trailer bulbs are
still working.
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Trailer Wiring Harness
The heavy-duty trailer wiring is an eight-wire harness
assembly. The harness is stored under the vehicle, on the
driver’s side corner frame rear crossmember. The
heavy-duty trailer wiring has a 30-amp feed wire
with
an in-line fuse located by the junct.ion block. See “Fuses
and Circuit Breakers”
in the Index. The harness does not
have a cannector 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.
0
0
0
0
0
0
0
0
Dark Blue: Use for electric trailer brakes or
auxiliary wiring.
Red: Use for battery charging;
it connects to the
starter solenoid.
Light Green: Back-up lamps.
Brown: Taillamps and parking lamps.
Yellow: Left stoplamp and turn signal.
Dark Green: Right stoplamp
and turn signal.
White (Heavy Gage): Ground wire.
White (Light Gage): 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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.dshield Wipers
I he windshield wiper motor is protected by a circuit
breaker and
a fuse. If the motor overheats due to heavy
snow or ice, the wipers 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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Tires (Continued)
Uniform Quality Grading
. . . . . . . . . . . . . . . . . . . . . . . 6-41
Wear Indicators
. . . . . . . . . . . . . . . . . . . . , . . . . . . . . . 6-40
When It’s Time for New
. . . . . . . . . . . . . . . . . . . . . . 6-40
TopStrap
..................................... 1-43
TorqueLock
.,..................................2-23
Torque, Wheel Nut . . . . . . . . . . . . . . . . . . . . . . . . . 5-29,6-60
Towing a Trailer
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-43
Towing, Recreational Vehicle
. . . . . . . . . . . . . . . . . . . . . 4-39
Towing Your Vehicle
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-7
Trailer Brakes
.....................................4-47
Driving on Grades . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-50
Driving with a Trailer . . . . . . . . . , , . . . . . . . . . . . . . . . 4-48
Hitches
.........................................
Maintenance When Towing . . . . . . . . . . . . . . . . . . . . . 4-5 1
Parking on Hills . . . . . . . . . . . . , . . . . . . . . . . . . . . . . . 4-50
Safety Chains
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-47
Tongueweight
...............................4-45
Total Weight on Tires . . . . , . . . . . . . . . . . . . . . . . . . . . 4-46
Towing
.........................................
TurnSignals .....................................
Weight .....................................4-45
Wiring Harness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-52
Transfer Case
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-20
Electronic
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-26
Transmission Fluid, Automatic
. . . . . . . . . . . . , . . . . . . . 6- 15
Transmitters, Keyless Entry . . . . . . . . . . . . . . . . . . . . . . . . 2-6
Transportation, Courtesy
. . . . . . . . . . . . . . . . . . . . . . . . . . 8-8
Trip, Before Leaving . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-33 Trip Odometer
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-61
TTYUsers
..................................... 8-4
Turn Signal and Lane Change Signals . . . . . . . . . . . . . . . 2-31
Turn Signals When Towing a Trailer
. . . . . . . . . . . . . . . . 4-49
Underbody Flushing
. . . . . . . . . . . . . . . . . . . . . . . . . . . 7-42
Underbody Maintenance
......................... 6-52
Universal Transmitter
. . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-53
Accessories
.....................................
Erasing Channels . . . . . . . . . . . . . . . . . . . . . , . . . . . . . 2-57
Operation
. . . . . . . . . . . . . . , . . . . . . . . . . . . . . . . , . . . 2-55
Programming
................................2-54
Rolling Code Openers . . . . . . . . . . . . . . . . . . . . . . . . . 2-56
Used Replacement Wheels
. . . . . . . . . . . . . . . . . . . . . . . . 6-44
Vehicle Control
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-6
Vehicle Damage Warnings
. . . . . . . . . . . . . . . . . . . . . . . . . . iv
Vehicle Dimensions
. . . . , . . . . . . . . . . . . . . . . . . . . . . . . 6-62
Vehicle Identification Number
. . . . . . . . . . . . . . . . . . . . . 6-54
Vehicle Loading
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-40
Vehiclestorage
....................................
Ventilation System . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . . 3-5
Visors, Sun
. . . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-50
Voltmeter
........,............................2-64
warning Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-2
Warning Lights, Gages and Indicators
. . . . . . . . . . . . . . . 2-62
Washer Fluid, Windshield
. . . . . . . . . . . . . . . . . . . . , . . . 6-26
Washing Your Vehicle
. . . . . . . , . . . . . . . . . . . . . . . . , . . 6-5 1
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