2004 GMC SIERRA air conditioning

Operation Tips
·
Keep the hood and front air inlets free of ice, snow,
or any other obstruction (such as leaves). The
heater and defroster will work far better, reducing
the chance of fogging the inside of your windows.
·Keep the air path under the front seats clear
of objects. This helps air to circulate throughout your
vehicle.
·Adding outside equipment to the front of your
vehicle, such as hood-air de¯ectors, etc., may affect
the performance of the heating and air conditioning
system. Check with your dealer before adding
equipment to the outside of your vehicle.
Warning Lights, Gages and
Indicators
Warning Lights, Gages, and
Indicators
This part describes the warning lights and gages that
may be on your vehicle. The pictures will help you
locate them.Warning lights and gages can signal that something is
wrong before it becomes serious enough to cause
an expensive repair or replacement. Paying attention to
your warning lights and gages could also save you
or others from injury.
Warning lights come on when there may be or is a
problem with one of your vehicle's functions. As you will
see in the details on the next few pages, some
warning lights come on brie¯y when you start the
engine just to let you know they're working. If you are
familiar with this section, you should not be alarmed
when this happens.
Gages can indicate when there may be or is a problem
with one of your vehicle's functions. Often gages
and warning lights work together to let you know when
there's a problem with your vehicle.
When one of the warning lights comes on and stays on
when you are driving, or when one of the gages shows
there may be a problem, check the section that tells you
what to do about it. Please follow this manual's advice.
Waiting to do repairs can be costly ± and even
dangerous. So please get to know your warning lights
and gages. They're a big help.
Your vehicle also has a driver information system that
works along with the warning lights and gages. See
Driver Information Center (DIC) on page 3-55.
3-33

(A) Light Truck (LT-Metric) Tire:The United States
version of a metric tire sizing system. The letter ªLTº as
the ®rst two characters in the tire size means a light
truck tire engineered to standards set by the U. S. Tire
and Rim Association.
(B) Tire Width:The three-digit number indicates the
tire section width in millimeters from sidewall to sidewall.
(C) Aspect Ratio:A two-digit number that indicates
the tire height-to-width measurements. For example, if
the tire size aspect ratio is ª75,º as shown in item ªCº of
the illustration, it would mean that the tire's sidewall is
75% as high as it is wide.(D) Construction Code:A letter code is used to
indicate the type of ply construction in the tire. The letter
ªRº means radial ply construction; the letter ªDº means
diagonal or bias ply construction; and the letter ªBº
means belted-bias ply construction.
(E) Rim Diameter:Diameter of the wheel in inches.
(F) Service Description:The service description
indicates the load range and speed rating of a tire. The
load index can range from 1 to 279. Speed ratings
range from ªAº to ªZº. The light truck tire size example
above shows dual or single tire con®gurations.Tire Terminology and De®nitions
Air Pressure:The amount of air inside the tire pressing
outward on each square inch of the tire. Air pressure
is expressed in pounds per square inch (psi) or
kilopascal (kPa).
Accessory Weight:This means the combined weight
of optional accessories. Some examples of optional
accessories are, automatic transmission, power steering,
power brakes, power windows, power seats, and air
conditioning.
Aspect Ratio:The relationship of a tire's height to its
width. Light Truck (LT-Metric) Tire
5-81

Fuses Usage
SUNROOF Sunroof
SEO B2 Off-Road Lamps
4WSVent Solenoid
Canister/Quadrasteer Module
Power
RR HVAC Not Used
AUX PWRAuxiliary Power Outlet Ð
Console
IGN 1 Ignition Relay
PCM 1 Powertrain Control Module
ETC/ECMElectronic Throttle Control,
Electronic Brake Controller
IGN EInstrument Panel Cluster, Air
Conditioning Relay, Turn
Signal/Hazard Switch, Starter
Relay
RTD Ride Control
TRL B/U Backup Lamps Trailer Wiring
PCM BPowertrain Control Module,
Fuel Pump
F/PMP Fuel Pump (Relay)Fuses Usage
B/U LPBack-up Lamps, Automatic
Transmission Shift Lock
Control System
RR DEFOG Rear Window Defogger
HDLP-HI Headlamp High Beam Relay
PRIME Not Used
02B Oxygen Sensors
SIRSupplemental In¯atable
Restraint System
FRT PARKFront Parking Lamps,
Sidemarker Lamps
DRLDaytime Running Lamps
(Relay)
SEO IGN Rear Defog Relay
TBC IGN1 Truck Body Controller Ignition
HI HDLP-LT High Beam Headlamp-Left
LH HID Not Used
DRL Daytime Running Lamps
IPC/DICInstrument Panel
Cluster/Driver Information
Center
5-132

Fuses Usage
HVAC/ECAS Climate Control Controller
CIG LTR Cigarette Lighter
HI HDLP-RT High Beam Headlamp-Right
HDLP-LOW Headlamp Low Beam Relay
A/C COMP Air Conditioning Compressor
A/C COMPAir Conditioning Compressor
Relay
RR WPR Not Used
RADIO Audio System
SEO B1Mid Bussed Electrical Center,
Rear Heated Seats,
HomeLink
LO HDLP-LT Headlamp Low Beam-Left
BTSIBrake Transmission Shift
Interlock System
CRANK Starting SystemFuses Usage
LO HDLP-RT Headlamp Low Beam-Right
FOG LP Fog Lamp Relay
FOG LP Fog Lamps
HORN Horn Relay
W/S WASHWindshield Washer Pump
Relay
W/S WASH Windshield Washer Pump
INFOOnStar/Rear Seat
Entertainment
RADIO AMP Radio Ampli®er
RH HID Not Used
HORN Horn
EAP Not Used
TREC All-Wheel Drive Module
SBA Supplemental Brake Assist
5-133

ApplicationCapacities
English Metric
VORTECŸ 8100 V8 (Vin G) 6.5 quarts 6.1 L
Fuel Tank
Short Bed 26.0 gallons 98 L
1500 Crew Cab 26.0 gallons 98 L
Long Bed 36.0 gallons 136 L
Chassis Cab (pickup Box Delete) 36.0 gallons 136 L
Chassis Cab 350027.0 gallons
23.0 gallons102 L (front)
87 L (rear)
Chassis Cab 3500 (California)27.0 gallons
23.0 gallons90 L (front)
87 L (rear)
Chassis Cab 3500 27.0 gallons 102 L (front)
Chassis Cab 3500 (California) 27.0 gallons 102 L (front)
Chassis Cab 3500HD27.0 gallons
23.0 gallons87 L (front)
68 L (rear)
Chassis Cab 3500HD 27.0 gallons 87 L (front)
Air Conditioning Refrigerant Capacity
Air Conditioning Refrigerant R-134a 1.6 lbs 0.7 kg
5-136

(b)Visually inspect front and rear suspension and
steering system for damaged, loose or missing parts,
signs of wear or lack of lubrication. Inspect power
steering lines and hoses for proper hook-up, binding,
leaks, cracks, cha®ng, etc. Visually check constant
velocity joints, rubber boots and axle seals for leaks.
(c)Visually inspect hoses and have them replaced if they
are cracked, swollen or deteriorated. Inspect all pipes,
®ttings and clamps; replace with genuine GM parts as
needed. To help ensure proper operation, a pressure test
of the cooling system and pressure cap and cleaning the
outside of the radiator and air conditioning condenser is
recommended at least once a year.
(d)Visually inspect wiper blades for wear or cracking.
Replace blade inserts that appear worn or damaged
or that streak or miss areas of the windshield.
(e)Make sure the safety belt reminder light and all your
belts, buckles, latch plates, retractors and anchorages
are working properly. Look for any other loose or
damaged safety belt system parts. If you see anything
that might keep a safety belt system from doing its
job, have it repaired. Have any torn or frayed safety belts
replaced. 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.)
(f)Lubricate all key lock cylinders, body door hinges,
hood latch assembly, secondary latch, pivots, spring
anchor, release pawl, tailgate hinges, tailgatelinkage,
tailgate handle pivot points, latch bolt, fuel door
hinge, locks and folding seat hardware. More frequent
lubrication may be required when exposed to a corrosive
environment. Applying silicone grease on weatherstrips
with a clean cloth will make them last longer, seal
better and not stick or squeak.
(g)Add ¯uid as needed. A ¯uid loss could indicate a
problem; repair as needed. Check vent hose at transfer
case for kinks and proper installation.
(h)Change automatic transmission ¯uid and ®lter if the
vehicle GVWR is over 8600 lbs. or if the vehicle is
mainly driven under one or more of these conditions:
þIn heavy city traffic where the outside temperature
regularly reaches 90ÉF (32ÉC) or higher.
þIn hilly or mountainous terrain.
þWhen doing frequent trailer towing.
þUses such as found in taxi, police or delivery
service.
(i)Drain, ¯ush and re®ll cooling system. See Engine
Coolant on page 5-33for what to use. Inspect hoses.
Clean radiator, condenser, pressure cap and ®ller neck.
Pressure test the cooling system and pressure cap.
6-9

A
Accessory Power Outlets.................................3-20
Adding a Snow Plow or Similar Equipment.........4-64
Adding Washer Fluid.......................................5-46
Additional Program Information........................... 7-9
Additives, Fuel................................................. 5-6
Add-On Electrical Equipment...........................5-125
Add-On Equipment..........................................4-63
Adjusting the Speakers
(Balance/Fade)..................3-76, 3-80, 3-91, 3-105
After Off-Road Driving.....................................4-37
Air Bag
Off Light.....................................................3-37
Passenger Status Indicator...........................3-40
Readiness Light..........................................3-36
Air Bag Systems.............................................1-70
Adding Equipment to Your Air Bag-Equipped
Vehicle...................................................1-86
Air Bag Off Switch.......................................1-76
How Does an Air Bag Restrain?....................1-75
Passenger Sensing System...........................1-81
Servicing Your Air Bag-Equipped Vehicle.........1-86
What Makes an Air Bag In¯ate?....................1-74
What Will You See After an Air Bag In¯ates?......1-75
When Should an Air Bag In¯ate?...................1-73
Where Are the Air Bags?..............................1-72
Air Cleaner/Filter, Engine.................................5-23
Air Conditioning..............................................3-30
Airbag Sensing and Diagnostic Module (SDM)....7-10All Overseas Locations...................................... 7-5
AM .............................................................3-129
AM-FM Radio.................................................3-74
Antenna, Fixed Mast......................................3-131
Antenna, XMŸ Satellite Radio Antenna
System.....................................................3-131
Anti-lock Brake System..................................... 4-7
Anti-Lock Brake, System Warning Light..............3-45
Appearance Care..........................................5-116
Care of Safety Belts...................................5-119
Chemical Paint Spotting..............................5-123
Cleaning the Inside of Your Vehicle..............5-117
Cleaning the Outside of Your Vehicle............5-120
Finish Damage..........................................5-122
Sheet Metal Damage..................................5-122
Underbody Maintenance.............................5-123
Vehicle Care/Appearance Materials...............5-123
Weatherstrips............................................5-119
Approaching a Hill..........................................4-27
Ashtrays........................................................3-21
Audio Output................................................3-123
Audio System(s).............................................3-73
AM-FM Radio.............................................3-74
Audio Steering Wheel Controls....................3-128
Care of Your Cassette Tape Player...............3-129
Care of Your CD and DVD Player................3-131
Care of Your CDs and DVDs.......................3-130
Chime Level Adjustment.............................3-131
Fixed Mast Antenna...................................3-131
Radio with Cassette and CD.........................3-88
1