2003 GMC SIERRA lock

1. Park the vehicle on a
level surface. You can
remove the coolant surge
tank pressure cap
when the cooling system,
including the coolant
surge tank pressure cap
and upper radiator
hose, is no longer hot.
Turn the pressure cap slowly counterclockwise
(left) about one full turn. If you hear a hiss, wait for
that to stop. A hiss means there is still some
pressure left.
2. Then keep turning the pressure cap slowly, and
remove it.
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A. Low-Beam Headlamp
B. High-Beam Headlamp
2. Pull the headlamp assembly out.
3. Unplug the electrical connector.
4. Turn the old bulb counterclockwise and remove it
from the headlamp assembly.
5. Put the new bulb into the assembly and turn it
clockwise until it is tight. Use care not to touch
the bulb with yourfingers or hands.
6. Plug in the electrical connector.
7. Put the headlamp assembly back into the vehicle.
Install and tighten the two pins.
Front Turn Signal, Sidemarker and
Daytime Running Lamps
A. Sidemarker Lamp
B. Retainer Clip
C. Front Turn Signal Lamp
D. Daytime Running Lamp (DRL)
1. Remove the headlamp assembly as mentioned
previously.
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2. Press the retainer clip (B), located behind the turn
signal housing, towards the outside of the vehicle.
3. Pull the turn signal housing out of the vehicle.4. Press the locking release lever, turn the bulb socket
counterclockwise and remove it from the turn signal
housing.
5. Remove the old bulb from the bulb socket.
6. Put a new bulb into the bulb socket. Use care not
to touch the bulb with yourfingers or hands.
7. Put the bulb socket back into the turn signal
housing and turn it clockwise until it locks.
8. Put the turn signal housing back into the vehicle
placing the hook and posts on the inner side into
the alignment holesfirst, then the outer side into the
retainer bracket until you hear a click.
9. Put the headlamp assembly back into the vehicle.
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Roof Marker Lamps
1. Remove the two
screws and lift off
the lens.2. Remove the six screws on the center roof marker
lamps.
3. Turn the old bulb counterclockwise to remove it
from the socket.
4. Put a new bulb into the
socket and turn
clockwise until it locks
in place.
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A. Cargo Lamps
B. Center High-Mounted Stoplamps
2. Remove the CHMSL bulb holder back plate from
the housing by pressing the release tabs.
3. Remove the CHMSL bulb by pulling the bulb
straight out from the holder back plate. Remove
a cargo bulb by turning the socket counterclockwise
and pulling the bulb straight out.4. If a CHMSL bulb is replaced, put the new bulb into
the socket and press it in until it is tight.
If a cargo lamp is replaced, put a new cargo lamp
bulb into the socket and press it in until it is
tight before turning the socket counterclockwise.
5. Put the bulb holder back plate into the lamp
housing.
6. Reinstall the lamp assembly and tighten the screws.
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3. Press the release tab and turn the bulb socket
counterclockwise to remove it from the taillamp
housing.
4. Pull the old bulb straight out from the socket.
5. Press a new bulb into the socket and turn the socket
clockwise into the taillamp housing until it clicks.
6. Reinstall the rear lamp assembly.
7. Close the tailgate.
Replacement Bulbs
Exterior Lamp Bulb Number
Low-Beam Headlamps 9005 or
9005 LL
(long life)
High-Beam Headlamps 9005
Daytime Running Lamps (DRL) 4114K
Front Roof Marker Lamps 194
Front Parking and Turn Lamps 3457A
Rear Marker Lamps, Taillamp and
Stoplamps3157
Rear Turn Lamps 3157
Back-up Lamps 3157
Center High-Mounted Stoplamp 912
Cargo Lamp 912
Fender Marker Lamps 194
For any bulb not listed here contact your dealer.
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Changing a Flat Tire
If a tire goesflat, avoid further tire and wheel damage
by driving slowly to a level place. Turn on your
hazard warningflashers.
{CAUTION:
Changing a tire can cause an injury. The
vehicle can slip off the jack and roll over you
or other people. You and they could be badly
injured. Find a level place to change your tire.
To help prevent the vehicle from moving:
1. Set the parking brakefirmly.
2. Put the shift lever in PARK (P).
3. Turn off the engine.
4. Put the wheel blocks at the front and rear
of the tire farthest away from the one
being changed. That would be the tire on
the other side of the vehicle, at the
opposite end.The following steps will tell you how to use the jack and
change a tire.
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Removing the Spare Tire and Tools
The equipment you’ll need is under the passenger’s
side second row seat. The spare tire is located
underneath the vehicle.
1. Pull up the second row seat with the loop at the
base of the seat cushion to access the tools.
2. The wheel blocks and the wheel block retainer can
be removed by turning the wing nut
counterclockwise.
3. To release the bottle jack from its holder, turn the
knob on the bottle jack counterclockwise to lower
the jack head slightly.4. There is also a wing nut used to retain the storage
bag and tools. To remove it, turn the wing nut
counterclockwise.
You’ll use the jack handle extensions and the wheel
wrench to remove the underbody-mounted spare tire.
A. Spare Tire (Valve Stem Pointed Down)
B. Hoist Assembly
C. Hoist Cable
D. Tire Retainer
E. Hoist Shaft
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