1996 GMC SIERRA wiring

Air Bag Readiness Light
There is an air bag readiness light on the instrument
panel, which shows AIR BAG. 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.
AIR
BAG
You will see this light flash
for a few seconds when you
turn your ignition
to RUN
or START. Then the light
should go out. This means
the system is ready.
Charging System Indicator Light
If the air bag readiness light doesn’t come on when you
start your vehicle, or stays on, or comes on when you
are driving, your air bag system may not work properly.
Have your vehicle serviced right away. This
light should come
on
briefly when you turn on the
ignition, before starting the
engine, as
a check to show
you it is working.
After the engine starts,
the light should go out. If it stays
on or comes on while
you are driving, you may have a
problem with your charging system. It could indicate a
problem with the alternator drive belt,
or some other
charging system problem. Have
it checked right away.
Driving while this light is on could drain your battery.
If
you must drive a short distance with this light on, it
helps to turn off all your accessories, such
as the radio
and air conditioner.
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Trailer Recommendations
You must subtract your hitch loads from the CWR for
your vehicle. Weigh your vehicle with
the trailer attached,
so that you won’t go over the GVWR or GAM.
You’ll get the best performance if you spread out the
weight
of your load the right way, and if you choose the
correct hitch and trailer brakes.
For more information, see “Trailer Towing” in the Index.
Camper Wiring Harness (Option)
A five-wire harness is stored in the front stake pocket on
the driver’s side of the bed. The harness has
no
connector and should be wired by a qualified electrical
technician.
It must be routed out. of your vehicle and
securely attached
so that it won’t be pulled or rubbed
while you’re using it. Store the harness in it’s original
position. Wrap the harness together and tie
it neatly so it
won’t be damaged.
Pickup Conversion to Chassis Cab
General Motors is aware that some vehicle owners may
consider having the pickup box removed and
a
commercial or recreational body installed. Before you
do so, first contact the GM Zone Office for your area for
information on such conversions specific to this vehicle. (See the
“Warranty and Owner Assistance” booklet for
Zone Office.) Owners should be aware that, as
manufactured, there are differences between
a chassis
cab and a pickup with
the box removed which may
affect vehicle
safety. The components necessary to adapt
a pickup to permit its safe use with a specialized body
should be installed by a body builder in accordance with
the information available from the Zone Office.
Towing a Trail-r
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
GM dealer for
advice and information about towing a trailer
with your vehicle.
I
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When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the pedal down
while
you:
0 Start your engine;
Shift into a gear; and
0 Release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the chocks.
Maintenance When Trailer Towing
Your vehicle will need service more often when you’re
pulling
a trailer. See the Maintenance Schedule for more
on this. Things
that are especially important in trailer
operation are automatic transmission fluid (don’t
overfill), engine oil, axle lubricant, belt, cooling system
and brake adjustment. Each of these is covered
in this
manual, and the Index will help you find them quickly.
If you’re trailering, it’s a good idea
to review these
sections before you start your trip.
Check periodically
to see that all hitch nuts and bolts
are tight.
Trailer Wiring Harness
A seven-wire harness is stored under the rear end of
your vehicle. between the frame rails. An electrical
connector
will need to be installed at the trailer end of
the harness, by a qualified electrical technician. For
additional trailer wiring and towing information please
consult your
GM dealer. 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
won’t bind or break when turning with the trailer, but
not so loose that it drags on the ground. Store the
harness in its original position. Wrap the harness
together and tie
it neatly so it won’t be damaged. If you
tow a trailer, your Center High-Mounted Stoplamp
(CHMSL) may not be properly visible from behind.
You should select a trailer with
a CHMSL on it or, if
one is not available, have one installed. See your GM
dealer about how to connect your vehicle’s wiring to
a trailer CHMSL.
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Electrical System
Ac . .-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 “Servicing
Your Air Bag-Equipped Vehicle”
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, 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 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.
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Fu ~ ~ s and Circuit Breakers
The wiring circuits in your vehicle are protected from
short circuits by a combination of
fuses, circuit breakers
and fusible thermal links. 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.
Instrument Panel Fuse Block
The fuse block access door
is on the driver’s side edge
of the instrument panel. Pull
off the cover
to access the
fuse block.
You can remove fuses with a fuse extractor. The fuse
extractor
is mounted to the fuse block access door. To
remove fuses if you don’t have a fuse extractor, hold the
end of the fuse between your thumb and index finger
and
pull straight out.
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Gear Positions. Automatic Transmission ............. 2- 13
Gear Positions. Manual Transmission .......... 2- 17. 2- 18
GloveBox .................................... 2-46
Gross Axle Weight Rating
........................ 4-42
Gross Vehicle Weight Rating
...................... 4-42
Guide en FranCais
11 .. .................................
GVWR ....................................... 4-42
Halogen Bulbs
................................ 6-37
Hazard Warning Flashers
.......................... 5- 1
Headlamps .................................... 2-39
Bulb Replacement
....................... 6.38. 6.39
High/Low Beam Changer
...................... 2-34
OnReminder
................................ 2-39
Wiring
..................................... 6-68
Head Restraints
................................. 1-5
Hearing Impaired. Customer Assistance
.............. 8-3
Heating
........................................ 3-4
High-Beam Headlamps
.......................... 2-34
Highway Hypnosis
.............................. 4-36
Hill and Mountain Roads
......................... 4-36
Hitches. Trailer
................................. 4-54
Hood
Checking Things Under ......................... 6-6
Release
...................................... 6-7
Horn
......................................... 2-32
Hydraulic Clutch Fluid
........................... 6-23
Hydroplaning
.................................. 4-32 Ignition
Positions
............................... 2-9
Illuminated Entry
............................... 2-42
Inflation. Tire
.................................. 6-49
Inside Daymight Rearview Mirror
................. 2-43
Inspections
.................................... 7-46
Brakesystem
................................ 7-47
Drive Axle
.................................. 7-47
Exhaust Systems
............................. 7-46
Radiator and Heater Hose
...................... 7-46
Steering
.................................... 7-46
Suspension
.................................. 7-46
Throttle Linkage
.............................. 7-46
Transfer Case (Four-wheel Drive)
............... 7-47
Instrument Panel
............................... 2-54
Cleaning
.................................... 6-61
Cluster
..................................... 2-56
FuseBlock
.................................. 6-69
Intensity Control
............................. 2-42
Interior Lamps
................................. 2-42
.................................... J ack. Tire 5-22
Jump Starting
................................... 5-2
Key
Lock Cylinders Service ..................... 7-43
Key Release Button ............................. 2- IO
Keyless Entry System ............................ 2-5
Keys .......................................... 2-1
9'
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Tape Player Care ............................... 3-24
Temperature Control. Climate Control System
..... 3- I. 3-3
Theft
.......................................... 2-7
Theft-Deterrent Feature
.......................... 3-2 1
Thermostat .................................... 6-30
Third Door ..................................... 2-3
Tilt Steering Wheel
............................. 2-33
Time. Setting the
................................ 3-7
Tirechains
.................................... 6-57
Tire Loading
................................... 4-42
Tires
......................................... 6-48
Alignment and Balance
........................ 6-55
Buying New ................................. 6-53
Chains
..................................... 6-57
Changing
a Flat .............................. 5-2 1
Cleaning .................................... 6-64
Inflation
.................................... 6-49
Inflation Check
............................... 7-42
Inspection and Rotation
........................ 6-50
Loading .................................... 4-42
Pressure
.................................... 6-49
Temperature
................................. 6-55
Traction .................................... 6-54
Treadwear ................................... 6-54
Uniform Quality Grading
....................... 6-54
Wear Indicators
.............................. 6-52
Wheel Replacement
........................... 6-55
When It’s Time for New
....................... 6-52
TopStrap
..................................... 1-39
TorqueLock
................................... 2-28
THEFTLOCK
TM ................................ 3-2 1
Torque. Wheel Nut ......................... 5.28. 6.75
Towing
a Trailer ................................ 4-46
Trailer
Towing
Your Vehicle
............................. 5-7
Brakes
..................................... 4-55
Driving on Grades
............................ 4-57
Drivingwith
................................. 4-55
Hitches ..................................... 4-54
Maintenance When Towing
..................... 4-59
Parking on
Hills .............................. 4-58
Safety Chains
................................ 4-55
Tongueweight ............................... 4-53
Total Weight on Tires
.......................... 4-54
Towing
..................................... 4-46
TurnSlgnals ................................. 4-57
Weight
..................................... 4-48
Wiring Harness
............................... 4-59
Transfer Case, Electronic ......................... 2-23
Transfer Case Lubricant
.......................... 6-25
Transfer Case, Manual
........................... 2-21
Transmission Fluid
Automatic
................................... 6-19
Manual
..................................... 6-22
Transmitters. Keyless Entry
........................ 2-5
Transportation, Courtesy
.......................... 8-6
Trip Odometer
................................. 2-57
TTYUsers
..................................... 8-3
Turn Signal
and Lane Change Signals ............... 2-34
Turn Signal/Multifunction Lever
................... 2-33
Turn Signals When Towing
a Trailer ................ 4-57
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Underbody Maintenance ........................ 6-65
Underhood Fuse/Relay Center ..................... 6-7 1
Underhood Reel Lamp ........................... 2-41
Underhood Storage ............................. 2-5 1
Vehicle
Control
...................................... 4-5
Damage Warnings .............................. iv
Identification Number ......................... 6-67
Loading .................................... 4-42
Storage
..................................... 6-37
Ventilation System ............................... 3-4
Visors, Sun
.................................... 2-53
Voltmeter ..................................... 2-60
warning Devices ............................... 5-2
Warning Lights.
Gages and Indicators ............... 2-58
Washer Fluid. Windshield ........................ 6-3 1
Washing Your Vehicle ........................... 6-62
Weatherstrips
.................................. 6-62
Wheel Alignment
.................................. 6-55
Nut Torque ............................. 5-28, 6-75
Replacement ................................. 6-55
Wrench ..................................... 5-22
Windows ..................................... 2-31
Lockout Switch .............................. 2-32
Manual ..................................... 2-31
Power ...................................... 2-31
Sliding Rear
................................. 2-32
Swing-Out
.................................. 2-32
Windshield Washer
............................. 2-35
Fluid .................................. 2-36, 6-31
Fluid Level Check
............................ 7-42
Windshield Wipers .............................. 2-35
Blade Replacement ...................... 6-47, 6-75
Winter Driving ................................. 4-38
Wiring, Headlamp
.............................. 6-68
Wrench, Wheel ................................. 5-22
Fuses ...................................... 6-68
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