1993 GMC SIERRA lock

Service & Amearance Care
5. Put the new bulb into the socket, gently press in on the bulb and turn it
clockwise until it is tight.
6. Put the socket back into the light assembly and turn it clockwise \
until it
locks.
7. Put the parkinghurn signal light assembly back into the vehicle\
and
tighten the screws.
Side Marker Bulb
II K2683
1. Remove the screws and pull out the parkinghurn signal light as\
sembly.
2. Reach through the opening and turn the side marker bulb socket
counterclockwise and remove it.
3. Pull the bulb straight out of the socket.
4. Put a new bulb into the socket and push it in until it is tight.
5. Put the socket back into the side marker assembly and turn it clockwise
to tighten it.
6. Replace the parkinghurn signal light assembly and tighten the s\
crews.
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Fender Marker Lights
I
1. Remove the screws and take the lens assembly out of the fender.
2. Turn the bulb socket counterclockwise and remove it from the lens
3. Pull the bulb straight out of the socket.
4. Put a new bulb into the socket and push it in until it is tight.
5. Put the socket back into the lens assembly and turn it clockwise to
6. Replace the lens and tighten the screws.
assembly.
tighten it.
PO248
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Service & Appearance Care
4. Push in gently on the bulb, turn it counterclockwise and remove it from
the socket.
5. Put in a new bulb and, pushing in gently, turn it clockwise 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 go on and
off, 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 a\
nd 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 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, protecting the circuit until the problem is fixed or goes away.
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.
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Fuse Block
K2644
The fuse block is in the instrument panel on the driver’s side.
You can remove fuses with a fuse extractor,
if you have one. 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.
Exhaust System
To help prevent damage to your exhaust system, do not continue to drive
your vehicle
if you notice:
Engine misfiring
Loss of performance
Other unusual operating conditions
Have your engine and exhaust system serviced regularly.
Three- Way Cataiytic Converter
Your vehicle’s three-way catalytic converter is designed to reduce the
pollutants in your vehicle’s exhaust. Use only unleaded fuel in your vehicle.
If
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Service & Appearance Care
Fuses and Circuit Breakers
Name
Gages
Turn-B/U EMCllgn
Inj. A
Brake
AC/Htr
Ctsy
Park LP P. Lps
StoplHaz. Wiper
Radio
Accll g n
.
Acc/Batt. Crank 4WD
DRL
Circuits Protected
Cruise Control, 4 WD Display Illum. Rear
Window Defogger Timer, Aux. Batt. Relay
Feed, Safety Belt Buzzer Timer, Cluster
Ign. Feed
Back-up Lamps, Turn Signals
T.C.C., Air Diverter, E.S.C., E.G.R., E.C.M.
Ign., R.W.A.L. Brake Switch
Throttle Body Injectors R.W.A.L., Cluster-Speed0
H.V.A.C.
4 WD, Aux. Batt. Relay
Dome Lamp, Cargo Lamp, Ctsy. and Glove
Box Lps. (TR-9), Radio (Memory-Clock)
Horn Relay, Horn Feed, Cigar Lighter, Park
Lamps
C49 SW Illum., Headlamp “On” Warning,
Radio Illum., H.V.A.C. Illum.
Haz. Flasher, Seat Belt Buzzer, Stop
Lmps., R.W.A.L. Memory
Windshield Wiper, Washer
Radio Feed
Pwr. Windows
Door Locks, Rear Window Defogger
Crank, Discreet Four Wheel Drive
Daytime Running Lights
Fuse
20 Amp
15 Amp
10 Amp
10 Amp
15 Amp
25 Amp
20 Amp
20 Amp
5 Amp
15 Amp
25 Amp
10 Amp
5 Amp
25 Amp
15 AmD
Circuit
Breaker
30 Amp
30 Amp
An inline fuse
is used for the underhood lamp
10 not use fuses of higher amperage than those recommended above.
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23. EXHAUST PRESSURE REGULATOR VALVE INSPECTION* -Check that
the valve works properly. Correct any binding. Inspect hoses fo\
r cracks, chafing or decay. Replace parts as needed.
24.
TIRE AND WHEEL ROTATION AND INSPECTION -For proper wear
and maximum tire life, rotate tires at the first
6,000 miles (1 0 000
kilometers) for Schedule I (t) or 7,500 miles (12 500 kilometers) for
Schedule
II (.) and then every 15,000 miles (25 000 kilometers)
thereafter. Follow the instructions and patterns shown in Section 6.
Check tires for uneven wear or damage.
If irregular or premature wear is
apparent, check wheel alignment. Also, check for damaged wheels.\
See
“Tires” in the Index for more information.
For dual wheels, whenever the vehicle, wheels, or fasteners are new,
have the wheel fastener torque set at the first 100,
1,000 and 6,000
miles (160, 1600 and 10
000 km).
For 3500 H.D. Models, block the tires opposite those being removed to
keep the vehicle from rolling.
25.
DRIVE AXLE SERVICE -Check readfront axle fluid level and add as
needed. Check constant velocity joints and axle seals for leaki\
ng.
Locking differential-Drain fluid at first oil change and refill. Check
fluid level and add as needed at subsequent oil changes.
In dusty
areas, or trailer towing applications drain fluid at every 15,0\
00 miles
(24 135 kilometers) and refill$
every oil change. In dusty areas, or trailer towing applications, drain
fluid every 15,000 miles
(24 135 kilometers) and refi1l.t
More frequent lubrication may be required on heavy-duty or off-road
use.
Standard differential -Check fluid level and add as needed at
26.
BRAKE SYSTEM INSPECTION -When the engine oil is changed,
inspect the lines and hoses for proper hookup, binding, leaks, \
cracks,
chafing, etc. Check the parking brake adjustment, and the fluid level in
the master cylinder.
A low fluid level can indicate worn disc brake pads
which may need to be sewiced.t
*An Emission Control Service
tA fluid
loss in these systems may indicate a problem. Have them
inspected and repaired at once.
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Scheduled Maintenance Sewices
When the wheels are removed for rotation, inspect disc brake pads f\
or wear
and rotors for surface condition.
Also inspect drum brake linings for wear and
cracks. Inspect other brake parts, including drums, wheel cylind\
ers, parking
brake, etc., at the same time. Remove any rust
or dirt from the wheel and
mounting surfaces before mounting the wheel.
Inspect brakes more often if driving habits or conditions resull In
frequent braking.
Owner Checks and Services
Listed below are owner checks and services which should be mad\
e at the
time period specified
to help ensure proper safety, emission performance, and
dependability of your vehicle.
Be sure any necessary repairs are completed at once. Whenever \
any fluids
or lubricants are added to your vehicle, make sure they are the proper ones,
as shown
in this Section.
At Least Once a Month
Tire inflation pressure check -Check the tires for proper inflation. If they
are low, inflate them
to the level specified on the certification label or on the
tire inflation charts. See “Loading Your Vehicle’’ or “Inflation-Tire Pressure” in
the Index.
At Least Once a Year
Key lock cylinder lubrication -Lubricate key lock cylinders with engine oil.
See the “Recommended Fluid and Lubricants’’ chart in this section.
Transmission neutral or clutch start switch operation
CAUTION
~
1. Before you start, be sure you have enough room around the veh\
icle.
2. Firmly apply both the manual parking brake and the regular brake. See
“Brakes” and “Parking Brake” in the Index.
Do not use the accelerator
pedal.
3. Be ready to turn off the engine immediately if it starts.
4. On automatic transmission vehicles, try to start the engine in each gear.
The starter should work only in
P (Park) or N (Neutral).
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On manual transmission vehicles, put the shift lever in N (Neutral), push the
clutch down halfway, and try to start the engine. The starter should work only
when the clutch is pushed down all the way to the floor.
Steering column lock operation -While parked, try to turn the key to Lock
in each gear shift position.
With an automatic transmission, the key should turn to
Lock only when the
gear shift is in
P (Park).
On vehicles with a key release lever, try to turn the key to
Lock without
pressing the lever. The key should turn to
Lock only with the key lever
depressed.
On all vehicles, the key should come out only in
Lock.
Parking brake and transmission
P (PARK) mechanism operation -
CAUTION I
4 When you are doing this check, your vehicle could begin to move.
You
or others could be injured and property could be damaged.
Make sure there is
room in front of your vehicle in case you begin
to
roll. Be ready to apply the regular brake at once should the
vehicle begin to move.
IW
Park on a fairly steep hill, with the vehicle facing downhill.\
Keeping your foot
on the regular brake, set the manual parking brake.
To check the parking brake: With the engine running and the
transmission in
N (Neutral), slowly remove foot pressure from the regular
brake pedal.
Do this until the vehicle is held by the parking brake only.
To check the “Park” mechanism’s holding ability: Apply the \
regular brake
and shift to
P (Park). Release the manual parking brake, then slowly
release the regular brake.
Lap and shoulder belts condition and operation -Inspect belt system,
including: webbing, buckles, latch plates, retractors, guide loop\
s and anchors.
Have a belt assembly replaced
if the webbing has been cut or otherwise
damaged.
Body
Lubrication Service -Lubricate all body door hinges with engine oil.
Also lubricate the tailgate, tailgate handle pivot points, and tailga\
te mounted
spare tire carrier
(if equipped). Lubricate the body hood, fuel door and rear
compartment hinges, latches and locks including interior glove
box and
console
doors, and any folding seat hardware. Lubricate the hood safety lever
pivot and prop
rod pivot. More frequent lubrication may be required when
exposed to a corrosive environment.
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