1994 GMC SIERRA wiring

EngineExhaust ........................................... 2-33
Running
Your Engine While You’re Parked ................... 2-33
Four-WheelDrive
......................................... 2-34
Transfer Case
.......................................... 2-35
Front Axle Locking Feature
............................... 2-36
Windows
................................................ 2-37
Horn
.................................................... 2-39
TiltWheel
............................................... 2-39
Multifunction Lever
........................................ 2-40
Turn Signal and Lane Change Indicator
...................... 2-40
Headlight High-Low Beam
............................... 2-41
Windshield Wipers
...................................... 2-42
Windshield Washer
...................................... 2-43
Cruise Control
.......................................... 2-44
Headlights and Vehicle Lighting
.............................. 2-49
Mirrors
.................................................. 2-54
SunVisors
............................................... 2-55
Cigarette LightedAshtrays ................................... 2-57
Storage Compartments
...................................... 2-58
Instrument Cluster
......................................... 2-67
Warning Lights and Indicators
............................. 2-69
Gages
................................................ 2-78
Center High-Mount Stop Lamp (CHMSL) Feed Wire ............. 2-82
Camper Wiring Harness
..................................... 2-83
Step Bumper Pad
.......................................... 2-84
Trailer Wiring Harness
...................................... 2-83
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Headlights and Vehicle Lighting
Your light switches
are on
the left side of
your instrument panel.
Push
the left side of the switch with the parking lights symbol on it to turn
on:
Parking Lights
Sidemarker Lights
Clearance Lights (if you have them)
Taillights
License Plate Lights
Instrument Panel Lights
0 Transfer Case Shift Indicator Light (if you have one)
Push the
left side of the switch with the master lighting symbol on it to turn
on all the lights listed above as well as the headlights.
Push the right side of the switch
with the off symbol on it to turn off your
lights.
Turn the dial
at the right of the off switch to adjust instrument panel lights.
Turning the dial all the way up
until it clicks turns on the interior lights.
You can switch your headlights from high to
low beam by pulling on the
turn signal/high beam lever.
A circuit breaker protects your headlights. If you have an electrical
overload, your headlights will flicker on and off. Have your headlight
wiring checked right away
if this happens.
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If equipment such as a cap or camper is installed, a wire labele\
d “Center
High Mount Stop lamp
(CHMSL) feed” is provided along the left rear frame
rail. This wire should be used to connect a
CHMSL on the cap or camper.
Camper Wiring Harness (Option)
An optional 5-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 its original position. Wrap the harness together and tie it
neatly so it won’t be damaged.
Trailer Wiring Harness (Option)
An optional 7-wire
harness is stored under
your vehicle along the
rear frame
crossmember. The
harness has a
30 amp.
in-line fused battery
feed wire and
no
connector, and should
be wired by a
qualified electrical
technician.
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.
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Before you start, check the trailer hitch and platform, safety chains,
electrical connector, lights, tires and mirror adjustment. If the trailer has
electric brakes, start your
vehicle and trailer moving and then apply the
trailer brake controller by hand to be sure the brakes are working. This lets
you check your electrical connection at
the same time.
During your trip, check occasionally to be sure that the load is secure, and
that the lights and any trailer brakes are still working.
Following Distance
Stay at least twice as far behind the vehicle ahead as you would when
driving your vehicle without a trailer. This can help
you avoid situations that
require heavy braking and sudden turns.
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
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 a different turn signal
flasher and extra wiring. The green arrows
on your instrument panel will
flash whenever you signal a turn or lane change. Properly hooked up, the
trailer lights will also flash, telling other drivers you’re about to turn,
change lanes or stop.
When towing a trailer, the green 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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A CAUTION:
It can be dangerous to get out of your vehicle if the shift lever is
not fully in “P” (Park) with the parking brake firmly set. Your
vehicle can roll.
If’ you have left the engine running, the vehicle can move
suddenly. You or others could be injured.
To be sure your vehicle
won’t move, even when you’re on fairly level ground, use the
steps that follow.
If you have four-wheel drive and your transfer case is in “N”
(Neutral), your vehicle will be free to roll, even if your shift lever
is in
“P” (Park). So, be sure the transfer case is in a drive gear
- not in “N” (Neutral).
If you are parking on a hill, or if you’re pulling a trailer, also see
“Parking
On Hills” in the Index.
When You Are Ready to Leave After Parking on a Hill
1. Apply your regular brakes and hold the pedal down while you:
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
fluid (don’t overfill), engine oil,
axle lubricant, belts, 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 Light Wiring
See “Trailer Wiring Harness” in the Index.
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4. Push in gently on
the bulb, turn it to
the left and
remove it from
the socket.
5. Put in a new bulb and, pushing in
gently, turn it to
the right until it is
tight.
6. Put the socket back in the light assembly and replace the lens and lens
seal.
Fuses 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 in the
wiring itself. This greatly reduces the chance of fires caused by electrical
problems. See “Fuses and Circuit Breakers” in the Index for more
information.
Headlights
The headlight wiring is protected by a circuit breaker in the \
light switch. An
electrical overload will cause the lights to flicker on and of\
f, or in some
cases to remain
off. If this happens, have your headlight 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. Although the circuit is protected from electrical \
overload,
overload due to heavy snow, etc., may cause .wiper linkage damage. Always
clear ice and heavy snow from the the windshield before using \
the
windshield wipers.
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 in the fuse panel protect the power windows and other
power accessories. When the current load is too heavy, the circuit breaker
opens and closes. This protects the circuit until the current \
load returns to
normal or the problem is fixed
.
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Trailer Wiring Harness
The optional seven-wire trailer wiring harness is protected by an in-line
fuse
in the battery feed wire. This fuse is near the junction block. See
“Trailer Wiring Harness”
in the Index for more information.
Fuse Block
The fuse block is
behind an access door
at the bottom of the
instrument panel,
next
to the parking brake
release lever.
To remove fuses if you don’t have one, hold the end of the fuse between
your thumb and index finger and pull straight out.
Be, sure to use the correct fuse.
If you ever have a problem on the road and
don’t have a spare fuse, you can “borrow” one of the correct value. 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 of the value you need. Replace
it as soon as you can. See “Fuses and Circuit Breakers“ in the Index for
more information.
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C
Camper Wiring Harness ........................................... 2-83
Capacities/Specification Charts ..................................... 6-91
CarbonMonoxide
............................................... 2-33
CargoLamp
.................................................... 2-52
Cassette Tape Player (see “Audio Systems”
)
Catalyticconverter .............................................. 6-64
Certificationire Label
........................................... 6-65
Changing a Flat Tire
......................................... 5-26, 5-32
Chemical Paint Spotting
........................................... 6-87
Child Restraints (See “Safety Belts”)
CHMSLFeedWire
.............................................. 2-82
Cigarette LightedAshtrays
..... ................................... 2-52
Circuit Breakers (See “Fuses”)
Cleaning
Finishcare
.................................................. 6-85
Glass
....................................................... 6-84
Insideofvehicle
.............................................. 6-81
Instrumentpanel. Top
.......................................... 6-83
Outsideofvehicle
............................................. 6-84
Special Problems
.............................................. 6-82
VinylorLeather
.............................................. 6-83
Wheels and Tires
.............................................. 6-86
Windshield
.................................................. 6-84
Clock
......................................................... 3-18
AM-FM Stereo Audio System with Cassette Deck
................... 3-11
AM-FM Stereo Audio System with Cassette Deck and Equalizer
... 3-14. 3-18
Conversion to Chassis Cab
........................................ 6-70
Coolant (See “Engine”)
Cooling System Capacity
.......................................... 5-17
Crankcase Capacity
.............................................. 6-93
Increasespeed
............................................... 2-46
CruiseControl
.................................................. 2-44
EraseSpeedMemory .......................................... 2-48
OnHills
..................................................... 2-48
Passing
..................................................... 247
Reducespeed
................................................ 2-47
Resume
..................................................... 2-46
Set
......................................................... 2-45
ToGetOutOf
................................................ 2-48
Customer Assistance for the Hearing or Speech Impaired
................. 8-3
Customer Satisfaction Procedure
..................................... 8-2
Daytime Running Lights (Canada Only)
......................... 2.50, 2.75
Indicator Light
.......................................... 2.50. 2.75
Diesel Fuel (See “Fuel”)
DomeLights
.................................................... 2-51
Doors
.......................................................... 2-7
Locks ........................................................ 2-5
Driving Across an Incline
............................................. 4-21
After Off-Road Driving
........................................ 4-22
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