1994 GMC SIERRA service indicator

Malfunction Indicator (Service Engine Soon) Lamp
The orange
SERVICE
ENGINE
SOON
A computer monitors the operation of your fuel, ignition and emission
control systems. This light should come on when the ignition
is on but the
engine is not running,
as a check to show you its working. If it does not
come
on at all, have it fixed right away. If it stays on, or comes on while you
are driving, the computer is indicating that you have a problem. You should
take your vehicle in for service soon.
NOTICE:
If you keep driving your vehicle with this light on, after a while
the emission controls won’t work
as well, your fuel economy
won’t be as good, and your engine may not run as smoothly.
This could lead to costly repairs not covered by your warranty.
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Check Gages Light
The orange Check
Gages light is located
near the lower right
corner
of the
instrument cluster.
This light
will come on briefly when you are starting the engine. If the light
comes
on and stays on while you are driving. it could indicate a problem
with your vehicle. It could be a problem with your oil pressure, coolant
temperature. or some other problem. Chcck your various gages
to see if they
are
in the warning zones. If they are, have your vehicle serviced right away.
Daytime Running Lights (DRL) Indicator Light
(Canada Only)
The green Daytime
Running Lights
(DRL) Indicator light,
if you have one, is
located near the upper
center
of the
instrument cluster.
If your vehicle was first sold. when new. in Canada, you will have this green
lighl on the instrument pancl.
It will light whenever the Daytime Running
Lights
are on. For more details about DRL, sce "Headlights and Vehicle
Lighting'.
in this section.
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Brake Wear
Your vehicle has front disc brakes and rear drum brakes. If you have a
C 3500 HD model, it has four-wheel disc brakes.
Disc brake pads have built-in wear indicators that make
a high-pitched
warning sound when the brake pads are worn and new pads are needed. The
sound may come and go or be heard
all the time your vehicle is moving
(except when you are pushing on the brake pedal firmly).
The brake wear warning sound means that sooner or later your
brakes won’t work well. That could lead to an accident.
When
you hear the brake wear warning sound, have your vehicle
serviced.
NOTICE:
Continuing to drive with worn-out brake pads could result in
costly brake repair.
Some driving conditions or climates may cause a brake squeal when the
brakes are first applied or lightly applied. This does not mean something is
wrong with your brakes.
If
you have rear drum brakes, they don’t have wear indicators, but if you
ever hear a rear brake rubbing noise, have
the rear brake linings inspected.
Also, the rear brake drums should be removed and inspected each time the
tires are removed for rotation or changing. When you have
the front brakes
replaced, have the rear brakes inspected, too.
Brake linings should always be replaced
as complete axle sets.
Brake Pedal Travel
See your dealer if the brake pedal does not return to normal height, or if
there is a rapid increase in pedal travel. This could be a sign of brake
trouble.
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Malfunction Indicator
(SERVICE ENGINE SOON) Lamp
The Malfunction Indicator (SERVICE ENGINE SOON) Lamp on your
instrument panel lets you know when
your emission system needs service.
The light
will come on briefly when you start your engine to let you know
that the system is working. If
it does not come on when you start your
engine,
or if it comes on and stays on while you’re driving, your system
may need service. Your vehicle should still be driveable, but
you should
have your system serviced right away.
Secondary Air hjection Reaction (AIR) System
You may have this system. It has a control valve that will direct air to where
it is needed. If the AIR system needs service, your Malfunction Indicator
(SERVICE ENGINE SOON) Lamp on your instrument panel will come on.
Loading Your Vehicle
SEE OWNERS MANUAL FOR ADDITIONAL INFORMATION
BlKG
The Certification/Tire
label is found on the
rear edge of the
driver’s door or
in the
Incomplete Vehicle
Document
in the cab.
The label shows
the size of your original tires and the inflation pressures
needed to obtain the gross weight capacity of your vehicle. This is called the
GVWR (Gross Vehicle Weight Rating). The GVWR includes the weight of
the vehicle, all occupants, fuel and cargo.
The Certification/Tire label also tells
you the maximum weights for the
front and rear axles, called Gross Axle Weight Rating (GAWR). To find out
the actual loads on your front and rear axles, you need to go to a weigh
station and weigh your vehicle. Your dealer can help you
with this. Be sure
to spread out your load equally
on both sides of the centerline.
Never exceed the GVWR for your vehicle, or
the GAWR for either the front
or rear axle.
And,
if you do have a heavy load, you should spread it out.
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Heater or A/C Control Lamp
Four Wheel Drive Indicator
rour Wheel Drive Shift Lever
Instrument Panel Compartment Lamp
Ashtray Lamp
Sunshade Vanity Mirror
"Crew Cab Only
LAMP OR BULB
INSTRUMENT PANEL
Transmission Indicator (PRNDL)
Daytime Running Lights Indicatory
Charging System Indicator Lamp
Instrument Cluster Illumination
--Gage Cluster
Instrument Cluster Illumination
-Tachometer Cluster
Headlamp Beam Indicator
Directional Signal Indicator
Brake Warning Indicator
Safety Belt Warning
Check Gages Indicator
Malfunction Indicator ("Service
Engine Soon") Lamp
Upshift Indicator
Glow Plugs Lamp*:$:
Low Coolant
Water
in Fuel Lamp*'$
Service Throttle Soon Lamp*"
194
161
194
194
I94 74
TRADE NO.
161
74
74
I94
I94 74 74
74
74 74
74
74
74
74
74
74
6
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L
Labels Certificatioflire
.............................................. 6-65
Truck-Camper
............................................... 6-68
Lights
......................................................... 2-70
BrakeSystemWarning
......................................... 2-70
Bulb Replacement
................................... 2-52.6-53. 6-98
Cargo Lamp
............................................ 2.58. 6.60
Charging System Light
......................................... 2-73
Check Gages Light
............................................ 2-75
CHMSL
..................................................... 2-82
DomeLights
................................................. 2-51
Fender
...................................................... 6-58
Front Parking/Turn Signal
....................................... 6-55
GlowPlugsLight
............................................. 2-72
Headlights (See “Headlights”)
Indicator
.................................................... 2-77
Low Coolant Warning
.......................................... 2-73
Malfunction Indicator
..................................... 2.74. 6.66
Reading
..................................................... 2-51
Service Engine
Soon ........................................... 2-74
Service Throttle Soon
.......................................... 2-72
SideMarker
.................................................. 6-58
Rear .................................................... 6-60. 6-61
Replacementchart
............................................ 6-98
RoofMarker
................................................. 6-59
TailgateMarker
................................................ 6-59
Underhood Reel Lamp
......................................... 2-53
WaterInFuel
................................................. 2-71
LoadingYourVehicle
............................................ 6-65
Lubrication
..................................................... 6-51
Accelerator Control System
..................................... 6-51
Body
....................................................... 6-51
Constant Velocity Joints
........................................ 6-51
FrontAxle
................................................... 6-37
Front Shock Absorbers
......................................... 6-49
Front Suspension and Steering Linkage
............................ 6-49
FrontWheelBearings
.......................................... 6-49
TailgateHandle
............................................... 6-52
Hood Latches and Hinge ........................................ 6-51
Hydraulic Clutch Grease Fitting
.................................. 6-35
Lockcylinders
............................................... 6-52
Propeller Shaft Slip Splines
..................................... 6-51
RearAxle ................................................... 6-35
Recommended Lubricants
...................................... 7-25
Transfer Case
................................................ 6-36
Operation
................................................... 249
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I
Service Do-It-Yourself
.......
Parts Identification Label
Publications
..........
Replacement Parts and Fj
Service Engine Soon Light
Service Station Checks
....
11
........................................ 6-3
....................................... 6-90
.................................... 8.6, 8.8
ter Recommendations
..................... 6-94
.................................. 2.74. 6-65
....................................... 7-28
Shift Indicator Light
......................................... 2.26, 2.76
ShiftingIntoPark
................................................ 2-30
Sliding Rear Window
............................................. 2-38
SpareTire
...................................................... 5-29
Pickup Bed Mounting
..................................... 5.31. 5-40
Specification Charts .............................................. 6-91
Speedometer
.................................................... 2-68
Starting your Diesel Engine
........................................ 2-16
Starting your Gasoline Engine
...................................... 2-12
Removal
.................................................... 5-29
Storage
..................................................... 5-39
Steering
........................................................ 4-8
Column Shift Lever
............................................ 2-30
InEmergencies
................................................ 4-9
Console
................................................ 2-59. 2-61
GarageDoorOpener
........................................... 2-61
GloveBox
................................................... 2-58
Other
....................................................... 2-65
SunVisors
..................................................... 2-55
Swing-Outwindows
............................................. 2-38
Storage Compartments
............................................ 2-58
T
Tachometer ..................................................... 2-69
Tailgate
......................................................... 2-8
Theft
........................................................... 2-9
Tiltwheel
...................................................... 2-39
Tires
.......................................................... 6-71
Chains
...................................................... 6-79
Flat
........................................................ 5-26
Balancing
................................................... 6-78
Changing a Flat
.......................................... 5.25, 5.32
Hub CapsNVheel Nut Caps
...................................... 5-32
InspectionRotation
....................................... 6-73. 6-75
Loading
..................................................... 2-39
New
........................................................ 6-76
Pressure
..................................................... 6-71
Spare (See “Spare Tire”)
Underbodycarrier
............................................ 5-29
Uniform Tire Quality Grading
................................... 6-77
TorqueLock
............................................... 2.29. 2.31
Towing
ATrailer
............................................... 4-38. 6.67
Maintenance
................................................. 4-44
Recommendations
............................................. 6-70
Turnsignals
................................................. 4-42
Following Distance
............................................ 4-42
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