2004 GMC SIERRA heater

How to Check and Add Fluid
The proper ¯uid should be added if the level does not
reach the bottom of the diaphragm when it's in place in
the reservoir. See the instructions on the reservoir cap.
Engine Coolant
The cooling system in your vehicle is ®lled with
DEX-COOLžengine coolant. This coolant is designed
to remain in your vehicle for 5 years or 150,000 miles
(240 000 km), whichever occurs ®rst, if you add only
DEX-COOL
žextended life coolant.
The following explains your cooling system and how to
add coolant when it is low. If you have a problem
with engine overheating, see
Engine Overheating on
page 5-36.A 50/50 mixture of clean, drinkable water and
DEX-COOL
žcoolant will:
·Give freezing protection down to-34ÉF (-37ÉC).
·Give boiling protection up to 265ÉF (129ÉC).
·Protect against rust and corrosion.
·Help keep the proper engine temperature.
·Let the warning lights and gages work as they
should.
Notice:Using coolant other than DEX-COOLžmay
cause premature engine, heater core or radiator
corrosion. In addition, the engine coolant may
require changing sooner, at 30,000 miles (50 000 km)
or 24 months, whichever occurs ®rst. Any repairs
would not be covered by your warranty. Always use
DEX-COOL
ž(silicate-free) coolant in your vehicle.
5-33

What to Use
Use a mixture of one-halfclean, drinkable waterand
one-half DEX-COOLžcoolant which won't damage
aluminum parts. If you use this coolant mixture,
you don't need to add anything else.
{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can boil
before the proper coolant mixture will. Your
vehicle's coolant warning system is set for the
proper coolant mixture. With plain water or the
wrong mixture, your engine could get too hot
but you would not get the overheat warning.
Your engine could catch ®re and you or others
could be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
žcoolant.
Notice:If you use an improper coolant mixture,
your engine could overheat and be badly damaged.
The repair cost would not be covered by your
warranty. Too much water in the mixture can freeze
and crack the engine, radiator, heater core and
other parts.
If you have to add coolant more than four times a year,
have your dealer check your cooling system.
Notice:If you use the proper coolant, you do not
have to add extra inhibitors or additives which claim
to improve the system. These can be harmful.
5-34

If No Steam Is Coming From Your
Engine
An overheat warning, along with a low coolant condition,
can indicate a serious problem. For more information,
see
Driver Information Center (DIC) on page 3-55.
If you get an engine overheat warning and don't have a
low coolant condition, but see or hear no steam, the
problem may not be too serious. Sometimes the engine
can get a little too hot when you:
·Climb a long hill on a hot day.
·Stop after high speed driving.
·Idle for long periods in traffic.
·Tow a trailer. See ªDriving on Gradesº under
Towing a Trailer on page 4-70.
If you get the overheat warning with no sign of steam,
try this for a minute or so:
1. If you have an air conditioner and it's on, turn it off.
2. Turn on your heater to full hot at the highest fan
speed and open the window as necessary.
3. If you're in a traffic jam, shift to NEUTRAL (N);
otherwise, shift to the highest gear while
driving ± AUTOMATIC OVERDRIVE
Xor
DRIVE (D) for automatic transmissions.If you no longer have the overheat warning, you can
drive. Just to be safe, drive slower for about 10 minutes.
If the warning doesn't come back on, you can drive
normally.
If the warning continues, pull over, stop, and park your
vehicle right away.
If there's still no sign of steam, push down the
accelerator until the engine speed is about twice as fast
as normal idle speed for at least three minutes while
you're parked. If you still have the warning,
turn off the
engine and get everyone out of the vehicleuntil it
cools down. Also, see ªOverheated Engine Protection
Operating Modeº listed previously in this section.
You may decide not to lift the hood but to get service
help right away.
5-38

The coolant level should
be at or above the FULL
COLD mark. If it isn't,
you may have a leak at the
pressure cap or in the
radiator hoses, heater
hoses, radiator, water
pump or somewhere else
in the cooling system.
{CAUTION:
Heater and radiator hoses, and other engine
parts, can be very hot. Do not touch them. If
you do, you can be burned.
Do not run the engine if there is a leak. If you
run the engine, it could lose all coolant. That
could cause an engine ®re, and you could be
burned. Get any leak ®xed before you drive the
vehicle.If there seems to be no leak, start the engine again.
The engine cooling fan speed should increase when idle
speed is doubled by pushing the accelerator pedal
down. If it doesn't, your vehicle needs service. Turn off
the engine.
Notice:Engine damage from running your engine
without coolant is not covered by your warranty. See
ªOverheated Engine Protection Operating Modeº
in the Index for information on driving to a safe
place in an emergency.
Notice:Using coolant other than DEX-COOLžmay
cause premature engine, heater core or radiator
corrosion. In addition, the engine coolant may
require changing sooner, at 30,000 miles (50 000 km)
or 24 months, whichever occurs ®rst. Any repairs
would not be covered by your warranty. Always use
DEX-COOL
ž(silicate-free) coolant in your vehicle.
5-40

{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can boil
before the proper coolant mixture will. Your
CAUTION: (Continued)
CAUTION: (Continued)
vehicle's coolant warning system is set for the
proper coolant mixture. With plain water or the
wrong mixture, your engine could get too hot
but you would not get the overheat warning.
Your engine could catch ®re and you or others
could be burned. Use a 50/50 mixture of clean,
drinkable water and a proper coolant.
Notice:In cold weather, water can freeze and crack
the engine, radiator, heater core and other parts.
Use the recommended coolant and the proper
coolant mixture.
{CAUTION:
You can be burned if you spill coolant on hot
engine parts. Coolant contains ethylene glycol
and it will burn if the engine parts are hot
enough. Do not spill coolant on a hot engine.
5-42

*1Ð Gasoline Engine and Diesel Engine.
*2Ð Gasoline Engine; ECMRPV Ð Diesel Engine.
*3Ð Gasoline Engine; FUEL HT Ð Diesel Engine.
*4Ð Gasoline Engine; ECM I Ð Diesel Engine.
*5Ð IGN/EDU
Fuses Usage
GLOW PLUGDiesel Glow Plugs and Intake
Air Heater
CUST FEED Gasoline Accessory Power
STUD #1Auxiliary Power (Single
Battery and Diesels Only)/
Dual Battery (TP2) Do not
install fuse.
MBECMid Bussed Electrical Center
Power Feed, Front Seats,
Right Doors
BLOWER Front Climate Control Fan
LBECLeft Bussed Electrical Center,
Door Modules, Door Locks,
Auxiliary Power OutletÐRear
Cargo Area and Instrument
Panel
Fuses Usage
STUD 2Accessory Power/Trailer
Wiring Brake Feed
ABS Anti-Lock Brakes
VSES/ECAS Vehicle Stability
IGN A Ignition Power
IGN B Ignition Power
LBEC 1Left Bussed Electrical Center,
Left Doors, Truck Body
Controller, Flasher Module
TRL PARK Parking Lamps Trailer Wiring
RR PARKRight Rear Parking and
Sidemarker Lamps
LR PARKLeft Rear Parking and
Sidemarker Lamps
PARK LP Parking Lamps Relay
STARTER Starter Relay
INTPARK Interior Lamps
STOP LP Stoplamps
TBC BATTTruck Body Controller Battery
Feed
5-131

Child Restraints (cont.)
Top Strap Anchor Location............................1-45
Where to Put the Restraint...........................1-42
Chime Level Adjustment.................................3-131
Cigarette Lighter.............................................3-21
Cleaning
Inside of Your Vehicle.................................5-117
Outside of Your Vehicle..............................5-120
Underbody Maintenance.............................5-123
Video Screen............................................3-131
Weatherstrips............................................5-119
Cleaning Aluminum or Chrome-Plated Wheels . . . 5-122
Cleaning Exterior Lamps/Lenses......................5-120
Cleaning Fabric/Carpet...................................5-117
Cleaning Glass Surfaces................................5-119
Cleaning Interior Plastic Components...............5-119
Cleaning Leather...........................................5-118
Cleaning the Mirror.................................2-57, 2-60
Cleaning the Top of the Instrument Panel.........5-119
Cleaning the Windshield and Wiper Blades.......5-121
Cleaning Tires..............................................5-122
Cleaning Vinyl..............................................5-118
Climate Control System...................................3-21
Dual..........................................................3-22
Dual Automatic............................................3-26
Clutch, Hydraulic.............................................5-32
Compass Calibration...............................2-57, 2-58
Compass Operation.........................................2-58Compass Variance..................................2-56, 2-59
Content Theft-Deferrent....................................2-19
Control of a Vehicle.......................................... 4-5
Coolant
Engine Temperature Gage............................3-46
Heater, Engine............................................2-25
Surge Tank Pressure Cap.............................5-36
Cooling System..............................................5-39
Crew Cab......................................................1-58
Cruise Control................................................3-11
Cruise Control Light........................................3-53
Cupholder(s)..................................................2-66
Current and Past Model Order Forms................7-13
Customer Assistance Information
Courtesy Transportation.................................. 7-7
Customer Assistance for Text Telephone (TTY)
Users....................................................... 7-4
Customer Assistance Offices........................... 7-4
Customer Satisfaction Procedure..................... 7-2
GM Mobility Program for Persons with
Disabilities................................................ 7-5
Reporting Safety Defects to General Motors....7-11
Reporting Safety Defects to the Canadian
Government............................................7-11
Reporting Safety Defects to the United States
Government............................................7-11
Roadside Assistance Program......................... 7-6
Service Publications Ordering Information........7-12
4

Electrical System (cont.)
Fuses and Circuit Breakers.........................5-126
Power Windows and Other Power Options....5-126
Windshield Wiper Fuses.............................5-126
Electronic Transfer Case..................................2-44
Emissions Inspection and Maintenance
Programs...................................................3-51
Engine
Air Cleaner/Filter.........................................5-23
Battery.......................................................5-52
Check and Service Engine Soon Light............3-49
Coolant......................................................5-33
Coolant Heater............................................2-25
Coolant Temperature Gage...........................3-46
Engine Compartment Overview......................5-12
Exhaust.....................................................2-53
Fan Noise..................................................5-44
Oil .............................................................5-18
Overheating................................................5-36
Starting......................................................2-23
ENGINE COOLANT HOT.................................3-68
Engine Hour Meter Display...............................3-35
Engine Oil Additives........................................5-21
ENGINE OVERHEATED..................................3-68
Entertainment System
Cleaning the Video Screen..........................3-131
DVD Distortion..........................................3-129
Entry Lighting.................................................3-19
Environmental Concerns..................................4-24
Event Data Records (EDR)..............................7-10Exit Lighting...................................................3-19
Express Down Windows..................................2-17
Extended Cab................................................1-58
Extended Cab and Crew Cab...........................1-55
Extender, Safety Belt.......................................1-32
Exterior Lamps...............................................3-14
F
Fifth Wheel and Gooseneck Trailering................4-90
Filter
Engine Air Cleaner......................................5-23
Finding a Program Type (PTY) Station
(RDS and XMŸ).......................3-80, 3-92, 3-105
Finding a Station..................3-75, 3-78, 3-90, 3-103
Finish Care..................................................5-120
Finish Damage.............................................5-122
Five-Speed (VORTECŸ 4300 V6 and
4800 V8 Engines)........................................2-31
Five-Speed (VORTECŸ 6000 V8 Engine)...........2-30
Fixed Mast Antenna.......................................3-131
Flash-to-Pass................................................... 3-9
Flat Tire........................................................5-95
Flat Tire, Changing.........................................5-96
Fluid
Automatic Transmission........................5-25, 5-28
Manual Transmission....................................5-31
Power Steering...........................................5-45
6