2003 GMC SONOMA tailgate

Keys...............................................................2-3
Remote Keyless Entry System.........................2-4
Remote Keyless Entry System Operation...........2-5
Doors and Locks.............................................2-8
Door Locks....................................................2-8
Power Door Locks..........................................2-9
Programmable Automatic Door Locks................2-9
Rear Door Security Locks..............................2-11
Lockout Protection........................................2-11
Leaving Your Vehicle....................................2-11
Third Door...................................................2-12
Tailgate.......................................................2-12
Windows........................................................2-14
Manual Windows..........................................2-15
Power Windows............................................2-15
Swing-Out Windows......................................2-16
Sliding Rear Window.....................................2-16
Sun Visors...................................................2-16
Theft-Deterrent Systems..................................2-17
Content Theft-Deterrent.................................2-17
Passlock
®....................................................2-19Starting and Operating Your Vehicle................2-20
New Vehicle Break-In....................................2-20
Ignition Positions..........................................2-20
Starting Your Engine.....................................2-22
Engine Coolant Heater..................................2-24
Automatic Transmission Operation...................2-25
Manual Transmission Operation......................2-28
Four-Wheel Drive..........................................2-29
Parking Brake..............................................2-32
Shifting Into Park (P).....................................2-33
Shifting Out of Park (P).................................2-35
Parking Your Vehicle.....................................2-36
Parking Over Things That Burn.......................2-36
Engine Exhaust............................................2-37
Running Your Engine While You Are Parked. . . .2-38
Mirrors...........................................................2-39
Manual Rearview Mirror.................................2-39
Automatic Dimming Rearview Mirror................2-39
Outside Manual Mirror...................................2-39
Outside Power Mirrors...................................2-40
Outside Convex Mirror...................................2-40
Outside Heated Mirrors..................................2-41
Section 2Features and Controls
2-1
2003 - Sonoma OM

Third Door
Your vehicle may be equipped with a third door for
convenience in loading and unloading cargo.
To open the third door,first open the driver’s front door.
Then, use the handle located on the front edge of the
door panel to open it.
You must close the third door before you can close the
driver’s door.
Tailgate
You can open the tailgate by pulling up on the handle
while pulling the tailgate down.
When you put the tailgate back up, be sure it latches
securely.
Follow these steps if you want to remove the tailgate:
1. Raise the tailgate slightly.
2. Remove both retaining
cables. To remove each
cable, turn it so the end
faces the front. Then,
push forward so the
larger part of the hole is
over the bolt. Pull the
end over the bolt.
2-12
2003 - Sonoma OM

3. With the tailgate halfway down, pull the tailgate
toward you at the left side and then move the
tailgate to the left to release the right side.
Reverse the procedure to reinstall the tailgate. Make
sure it is secure.
2-13
2003 - Sonoma OM

Taillamps
1. Open the tailgate.
2. Remove the screws
from the lamp
assembly near the
tailgate latch.
3. Pull the assembly away from the pickup side panel.
4. Turn the socket counterclockwise to remove it.
Push the tab in while you turn the socket.
5. Pull the bulb out.
6. Push the new bulb into the socket.
7. Put the socket into the assembly and turn the
socket clockwise until it locks in place.
8. Reinstall the assembly. Install and tighten the
screws.
9. Close the tailgate.
Replacement Bulbs
Exterior Lamp Bulb Number
Halogen Headlamps
Composite Low-Beam
Composite High-Beam9006 HB4 or
9006 LL
9005 HB3
Tail and Stoplamps 3057
Rear Sidemarker Lamps 194
Front Sidemarker Lamps 194NA
Front Turn Signal Lamps 3457A
Center High–Mounted Stoplamp 211–2
*For replacement bulbs not listed here,
please consult your dealer.
5-55
2003 - Sonoma OM

Also look for any opened or broken air bag coverings,
and have them repaired or replaced. (The air bag
system does not need regular maintenance.)
Wiper Blade Check
Inspect wiper blades for wear or cracking. Replace
blade inserts that appear worn or damaged or that
streak or miss areas of the windshield. Also see
Cleaning the Outside of Your Vehicle on page 5-82.
Spare Tire Check
At least twice a year, after the monthly ination check of
the spare tire determines that the spare is inated to
the correct tire ination pressure, make sure that
the spare tire is stored securely. Push, pull, and then try
to rotate or turn the tire. If it moves, use the wheel
wrench to tighten the cable. SeeChanging a Flat Tire
on page 5-68.
Weatherstrip Lubrication
Silicone grease on weatherstrips will make them last
longer, seal better, and not stick or squeak. Apply
silicone grease with a clean cloth. During very cold,
damp weather more frequent application may be
required. SeePart D: Recommended Fluids and
Lubricants on page 6-33.
Manual Transmission Check
Check the transmissionuid level; add if needed.
SeeManual Transmission Fluid on page 5-23. Check
for leaks. Auid leak is the only reason foruid
loss. Have the system inspected and repaired if needed.
Automatic Transmission Check
Check the transmissionuid level; add if needed.
SeeAutomatic Transmission Fluid on page 5-20.Auid
loss may indicate a problem. Check the system and
repair if needed.
Hydraulic Clutch System Check
Check theuid level in the clutch reservoir. See
Hydraulic Clutch on page 5-24.
Auid loss in this system could indicate a problem.
Have the system inspected and repaired at once.
At Least Four Times a Year
Tailgate Lubrication Service
Lubricate tailgate latch bolt, handle assembly pivot
points, and hinges with lubricant recommended
in Part D.
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2003 - Sonoma OM

Usage Fluid/Lubricant
Rear Axle
(Locking
Differential)Axle Lubricant; use only GM Part
No. U.S. 1052271, in Canada
10950849.Do not add friction
modier.
Transfer CaseDEXRON
®-III Automatic
Transmission Fluid.
Transfer Case
Shift LeverChassis Lubricant (GM Part No.
U.S. 12377985, in Canada
88901242, or equivalent) or lubricant
meeting requirements of NLGI #2,
Category LB or GC-LB.
Rear Driveline
Center Spline
and Universal
JointsChassis Lubricant (GM Part No.
U.S. 12377985, in Canada
88901242, or equivalent) or lubricant
meeting requirements of NLGI #2,
Category LB or GC-LB.
Constant
Velocity
Universal JointChassis Lubricant (GM Part No.
U.S. 12377985, in Canada
88901242, or equivalent) or lubricant
meeting requirements of NLGI #2,
Category LB or GC-LB.
Clutch Pushrod
to Clutch Fork
JointChassis Lubricant (GM Part No.
U.S. 12377985, in Canada
88901242, or equivalent) or lubricant
meeting requirements of NLGI #2,
Category LB or GC-LB.
Usage Fluid/Lubricant
Hood Latch
Assembly,
Secondary
Latch, Pivots,
Spring
Anchor and
Release PawlLubriplate
®Lubricant Aerosol (GM
Part No. U.S. 12346293, in Canada
992723, or equivalent) or lubricant
meeting requirements of NLGI #2,
Category LB or GC-LB.
Hood and Door
Hinges, Fuel
Filler Door and
Folding SeatsMulti-Purpose Lubricant, Superlube
®
(GM Part No. U.S. 12346241, in
Canada 10953474, or equivalent).
Tailgate Handle
Pivot Points,
Hinges, Latch
Bolt and
LinkageMulti-Purpose Lubricant, Superlube
®
(GM Part No. U.S. 12346241, in
Canada 10953474, or equivalent).
Weatherstrip
ConditioningDielectric Silicone Grease (GM Part
No. U.S. 12345579, in Canada
10953014, or equivalent).
Weatherstrip
SqueaksSynthetic Grease with Teon,
Superlube
®(GM Part No. U.S.
12371287, in Canada 10953437,
or equivalent).
6-34
2003 - Sonoma OM

Stalling on an Incline.......................................4-24
Starter Switch Check.......................................6-28
Starting Your Engine.......................................2-22
Shifting Into................................................2-22
Starting Your VORTEC™2200 L4 Engine............ 6-4
Starting Your VORTEC™4300 V6 Engine..........2-23
Steering.......................................................... 4-8
Steering in Emergencies.................................... 4-9
Steering, Suspension and Front Drive
Axle Boot and Seal Inspection.......................6-31
Steering Tips................................................... 4-8
Storage
Garment Hooks...........................................2-50
Storage Areas
Front Storage Area......................................2-49
Glove Box..................................................2-41
Luggage Carrier..........................................2-50
Overhead Console.......................................2-42
Storing a Flat or Spare Tire and Tools...............5-76
Stuck in Sand, Mud, Ice or Snow......................4-40
Sun Visors.....................................................2-16
Sunglasses Storage Compartment.....................2-46
Sunroof.........................................................2-52
Swing-Out Windows........................................2-16
T
Tachometer....................................................3-23
Tailgate.........................................................2-12Tailgate Lubrication Service..............................6-27
Taillamps.......................................................5-55
Temperature and Compass Display....................2-44
Testing the Alarm............................................2-18
Theft-Deterrent, Radio.....................................3-67
Theft-Deterrent Systems...................................2-17
Content Theft-Deterrent
................................2-17
Passlock
®...................................................2-19
Third Door
.....................................................2-12
Throttle System Inspection
...............................6-32
Tilt Wheel
........................................................ 3-4
Time Delay
....................................................2-39
Tire Inflation Check
.........................................6-26
Tires
.....................................................5-58, 5-84
Buying New Tires
........................................5-62
Chains
.......................................................5-66
Changing a Flat Tire
....................................5-68
Compact Spare Tire
.....................................5-78
If a Tire Goes Flat
.......................................5-67
Inflation–Tire Pressure
...............................5-58
Inspection and Rotation
................................5-60
Uniform Tire Quality Grading
.........................5-63
Wheel Alignment and Tire Balance
.................5-64
Wheel Replacement
.....................................5-65
When It Is Time for New Tires
......................5-61
To Use the Engine Coolant Heater
....................2-24
Top of the Instrument Panel
.............................5-81
Top Strap
......................................................1-41
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2003 - Sonoma OM