1993 GMC SIERRA service indicator

Malfunction Indicator Lamp (Service Engine Soon Light)
I
SERVICE
EF_'31NE
SOON
K2329
A computer monitors operation of your fuel, ignition, and emission control
systems. This light should come on when the ignition is on bu\
t the engine is not running, as a check to show you it is 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
E
If you keep driving your vehicle with this light on, after awhile the emission
controls won't work 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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Your Driving and fhe Road
Brake System Warning Light
K2325
This light appears on your instrument cluster to warn you if your regular
braking’ system needs service. See “Brake System Warning L\
ight” in the
Index.
Disc Brake Wear Indicators
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 war\
ning sound
when the brake pads are worn and new pads are needed. The so\
und m’ay
come and go or be heard all the time your vehicle is moving (except \
when
you are pushing on the brake pedal firmly).
1 CAUTION
The brake wear warning sound means that sooner or later your
hear the brake wear warning sound, have your vehicle serviced. \
5 brakes won’t work well. That could lead to an accident. When you I ~
I 1
i
~ i
brakes are first applied or lightly applied. This does not mea\
n something is
wrong with your brakes.
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you use leaded fuel, you could damage your three-way catalytic converter,
and other engine components.
Computer Command Control System (All TBI equipped
vehicles and diesel engine vehicles below
8,500 lbs. GVWR)
Gasoline Engines
This system has an oxygen (OS) sensor that helps keep your engine’s air-fuel
mixture at a proper level. Use only unleaded fuel in your veh\
icle.
If you use
leaded fuel, you could damage your oxygen
(OS) sensor and three-way
catalytic converter.
Diesel Vehicles Below 8,500 LBS. GVWR
This system monitors engine speed and throttle position. It adj\
usts exhaust gas recirculation to limit emissions.
The Malfunction Indicator Lamp
(SERVICE ENGINE SOON) on your
instrument panel lets you know when your emission control syste\
m needs
service. The light will come on briefly when you start your e\
ngine 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 Injection (AIR) System
You may have this system. It lets you know if your engine control module,
wiring harness or solenoid need service.
If the Malfunction Indicator Lamp
(Service Engine Soon) comes on, you need service.
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Service & Appearance Cam
When It’s Time for New Tires
K1656
One way to tell when it’s time for new tires is to check the treadwear
indicators, which will appear when your tires have only
2/32 inch (1.6 mm) or
less of tread remaining.
You need a new tire
if:
You can see the indicators at three places around the tire.
You can see cord or fabric showing through the tire’s rubber.
The tread or sidewall is cracked, cut or snagged deep enough to show
cord
or fabric.
The tire has a bump, bulge or split.
The tire has a puncture, cut, or other damage that can’t be repalred well
because of the size or location of the damage.
Dual Tire Operation
If your vehicle has dual rear wheels, the outer tire will usually\
wear faster
than the inner tire. Your tires will wear more evenly and last longer
if you
rotate the tires periodically.
If you’re going to be doing a lot of driving on
high-crown roads, you can reduce tire wear by adding
5 psi (35 kPa) to the
tire pressure in the outer tires. Be sure to return
to the recommended
pressures when no longer driving under those conditions.
6-80
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I I Power Rating I 1
Lamp or Bulb
Malfunction Indicator (“Service Engine
Quantity
at 12.8V, Watts Trade No.
Soon”)
“Diesel only
**Crew Cab Only tCanadian Vehicles only t0390
1 .7
74
Service Fuel Filter Lamp*
1 .7
74
Low Coolant Lamp*
1 .7 74 Glow Plugs Lamp*
1 .7
74
Upshift Indicator
1 .7
74
Service Replacement Part and Filter Recommendations
Engine
(VIN)
4.3 (Z)
5.0 (H)
5.7 (K)
6.2 (C)
6.2
(J)*
6.5 (F)*
7.4
(N)
-
Oil
Filter
PF51
PF35t
PF35t
PF35
PF35
PF35
PF35
-
Air
Cleaner
A1 78CW A348C
A348C
A644C A644C
A917C
A348C
PCV
Valve
CV789C
cv774c
cv774c
-
-
-
cv774c I I
tFour Wheel Drive Vehicles use a PF51
*Heavy
Duty Emission Engine
1,
Spark** Plugs
CR43TS
.CR43TS
.CR43TS
-
-
.CR43TS
oil filter
’*Use AC copper-cored resistor type spark plugs.
Fuel
Filter
GF481
GF481
GF481
TP 1
006
TP 1 006
TP1006
GF481
-I
RC36
RC36
RC32
RC32
RC32
RC36
t0039
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INDEX
H
Halogen Bulbs .............................. 6-55
Hazard Warning Flashers
.............. 5-2
Head Restraints
.............................. 1-5
Headlights .......................... 2.53. 6-55
Composite
.................................. 6-56
Halogen
..................................... 6-55
High-Low Beam
........................ 2-44
Reminder
................................... 2-54
Sealed Beam
............................. 6-55
Heating System (with NC)
........... 3-5
Rear Window Defogger
............. 3-8
System Controls
......................... 3-6
Fan Knob
..................................... 3-4
Function Lever
............................ 3-4
Temperature Lever
...................... 3-4
Hitches
........................................... 4-58
Hood Checking Under
........................ 6-17
Latches and Hinge
................... 6-53
Release
...................................... 6-1 7
Horn
............................................... 2-41
Hydraulic Clutch
........................... 6-37
Grease Fitting
............................ 6-39
Hydro-Boost System (Hydraulic Pump)
..................... 6-50
Hydroplaning
................................. 4-39
I
If You’re Stuck In Sand. Mud.
Ice or Snow
.............................. 5-33
Ignition Switch
.............................. 2-1 0
Inflation-Tire Pressure ................. 6-73
Instrument Panel
............... 2-70. 2-76
Diesel Tach Cluster .................. 2-75
Standard Cluster
............ 2-72, 2-73
J
High Beam Indicator Light ...... 2-85
Heating System (without AIC)
..... 3-4
Rear Window Defogger
............. 3-8
Highway Hypnosis
........................ 4-46 Jack Storage
...................... 5.19.
5-31
Jump Starting
................................ 5-3
K
Key Release Lever ....................... 2-11
Keys
................................................. 2-3
L
Lights ............................................. 2-53
Brake System Warning
............ 4-18
Bulb Replacement
......... .6-54, 6-98
Cargo Lamp
.................... 2-58, 6-61
Charging System Light
........... 2-82
Check Gages Light
.................. 2-84
Dome Lights
............................. 2-56
Fender
........................................ 6-59
Fog Lamps
................................ 2-54
Glow Plugs Light
........... 2-16, 2-81
Front ParkinglTurn Signal
........ 6-57
Indicator
..................................... 2-78
Headlights (See “Headlights”-)
Low Coolant Warning
.............. 2-81
Malfunction Indicator
.... 2-83, 6-66
Operation
................................... 2-43
Reading
..................................... 2-57
Service Fuel Filter
.................... 2-80
Side Marker
.............................. 6-58
Rear
................................. 6-62, 6-63
Replacement Chart
.................. 6-98
Roof Marker
.............................. 6-60
Tailgate Marker
......................... 6-60
Underhood Reel Lamp
............ 2-58
Loading Your Vehicle
........ 4-26, 6-67
Truck-Camper
............................ 6-70
Lubrication
..................................... 6-52
Accelerator Control System
.... 6-52
Body ........................................... 6-53
Constant Velocity Joints
......... 6-53
Front Axle
................................. 6-40
Front Shock Absorbers
........... 6-51
Front Suspension and Steering Linkage
................... 6-51
Service Engine Soon
..... 2-83, 6-66
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S
Safety Belts .................................. 1-1 1
Center Passenger Position
...... 1-26
Cleaning
..................................... 6-87
Checking Restraint System
..... 1-52
Child Restraints
........................ 1-37
Children
..................................... 1-35
Driver Position
.......................... 1-1 8
Extender
.................................... 1-52
Lap Shoulder
............................. 1-19
Larger Children
.......... : .............. 1-50
Proper Wear
.............................. 1-1 8
Questions and Answers
.......... 1-1 6
Rear Seat Passengers
............. 1-29
Reminder Light
......................... 1-1 7
Replacing After a Crash
.......... 1-53
Right Front Passenger Position
.................................. 1-25
Small Children and Babies
..... 1-36
Use During Pregnancy
............. 1-24
Why They Work
........................ 1-13
Safety Chains
............................... 4-58
Safety Warnings and Symbols
..... 0-2
Scheduled Maintenance Services
................ 7-3, 7-4, 7-18
Seats
Controls
........................................ 1-2
Easy Entry Seat
.......................... 1-8
Latches
.............................. 1-5, 1-10
Manual Front
............................... 1-2
Power Driver’s
............................ 1-3
Rear
.............................................. 1-9
Reclining
..................................... 1-3
Do-It-Yourself
............................... 6-3
Parts Identification Label
......... 6-94
Publications
........................ 8-6, 8-8
Replacement
. Parts and
Filter Recommendations
...... 6-99
Light
................................ 2-83, 6-66
Adults
........................................ 1-1
8
Service
Service Engine Soon Service Station Checks
............... 7-28
Shift Indicator Light
.......... 2.27. 2-85
Shifting Into Park
........................ 2-30
Single Belt Accessory Drive
...... 6-51
Sliding Rear Window
.................. 2-40
Spare Tire
..................................... 5-20
Pickup Bed Mourrting
.... 5.23. 5-32
Removal
..................................... 5-21
Storage
...................................... 5-31
Specification Charts
.................... 6-95
Speedometer
................................ 2-76
Starting Your Diesel Engine
....... 2-15
Starting Your Gasoline Engine
... 2-12
Steering
......................................... 4-19
Column Shift Lever
.................. 2-31
In Emergencies
........................ 4-21
Storage Compartments
............... 2-63
Console
........................... 2.64. 2-65
Glove Box
................................. 2-63
Other
.......................................... 2-68
Sun Visors
.................................... 2-61
Swing-Out Windows
.................... 2-40
T
Tachometer ........................ 2-76, 2-78
Tailgate
............................................ 2-8
Theft
................................................ 2-9
Thermostat
.................................... 6-46
Tilt Wheel
..................................... 2-41
Tires
............................................... 6-72
Balancing
................................... 6-82
Chains
........................................ 6-84
Changing a Flat
............. 5-17, 5-23
Flat
............................................. 5-17
Hub CapsNVheel Nut Caps
.... 5-24
Inspection/Rotation
........ 6-78. 6-79
Loading
...................................... 6-67
New
................................. 6-80. 6-81
Pressure
..................................... 6-73
Spare (See “Spare Tire”) Underbody Carrier
................... 5-21
Uniform Tire Quality Grading
. 6-81
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