2004 GMC SIERRA DENALI heater

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.
5-22

If No Steam Is Coming From Your
Engine
An overheat warning, along with a low coolant condition,
can indicate a serious problem. See ªLow Coolantº
under
DIC Warnings and Messages on page 3-57.
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 4-58.If you get the overheat warning with no sign of steam,
try this for a minute or so:
1. If your air conditioner is 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 (
X)
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 Overheated Engine Protection
Operating Mode listed previously in this section.
You may decide not to lift the hood but to get service
help right away.
5-27

Cooling System
When you decide it's safe to lift the hood, here's what
you'll see:
A. Coolant Surge Tank
B. Coolant Surge Tank Pressure Cap
C. Engine FanIf the coolant inside the coolant surge tank is boiling,
don't do anything else until it cools down. The vehicle
should be parked on a level surface.
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.
5-28

{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.
5-29

{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: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.
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.
5-31

*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
Outlet Ð Rear 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
5-111

Chime Level Adjustment..................................3-88
Cigarette Lighter.............................................3-19
Cleaning
Inside of Your Vehicle..................................5-96
Outside of Your Vehicle................................5-99
Underbody Maintenance.............................5-102
Weatherstrips..............................................5-98
Cleaning Aluminum or Chrome-Plated
Wheels.....................................................5-101
Cleaning Exterior Lamps/Lenses.......................5-99
Cleaning Fabric/Carpet....................................5-96
Cleaning Glass Surfaces..................................5-98
Cleaning Interior Plastic Components.................5-98
Cleaning Leather............................................5-97
Cleaning the Mirror.........................................2-33
Cleaning the Top of the Instrument Panel...........5-97
Cleaning the Windshield and Wiper Blades.......5-100
Cleaning Tires..............................................5-101
Cleaning Vinyl................................................5-97
Cleaning Wood Panels....................................5-98
Climate Control System
Dual Automatic............................................3-19
Compass Calibration.......................................2-33
Compass Variance..........................................2-32
Content Theft-Deferrent....................................2-16
Control of a Vehicle.......................................... 4-5Coolant
Engine Temperature Gage............................3-38
Heater, Engine............................................2-20
Surge Tank Pressure Cap.............................5-24
Cooling System..............................................5-28
Cruise Control.................................................. 3-8
Cruise Control Light........................................3-44
Cupholder(s)..................................................2-42
Current and Past Model Order Forms................7-12
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...................................7-10
Roadside Assistance Program......................... 7-6
Service Publications Ordering Information........7-11
4

D
Daytime Running Lamps..................................3-14
Defensive Driving............................................. 4-2
Defogging and Defrosting.................................3-25
Delayed Locking............................................... 2-8
Doing Your Own Service Work........................... 5-3
Dome Lamps.................................................3-17
Door
Delayed Locking........................................... 2-8
Locks.......................................................... 2-6
Power Door Locks......................................... 2-7
Programmable Automatic Door Locks............... 2-8
Rear Doors.................................................2-11
Driver
Position, Safety Belt.....................................1-14
DRIVER DOOR AJAR.....................................3-59
Driver Information Center (DIC).........................3-46
DIC Operation and Displays..........................3-46
DIC Warnings and Messages........................3-57
Driving
At Night.....................................................4-32
City...........................................................4-36
Defensive..................................................... 4-2
Drunken....................................................... 4-2
Freeway.....................................................4-37
Hill and Mountain Roads..............................4-40
In Rain and on Wet Roads...........................4-33
Winter........................................................4-42
Driving Across an Incline..................................4-28Driving Downhill..............................................4-26
Driving in Mud, Sand, Snow or Ice....................4-29
Driving in Water..............................................4-30
Driving On Grades..........................................4-67
Driving on Off-Road Hills.................................4-22
Driving on Snow or Ice....................................4-43
Driving Through Deep Standing Water...............4-35
Driving Through Flowing Water.........................4-35
Driving Uphill..................................................4-24
Driving with a Trailer.......................................4-65
Dual Automatic Climate Control System.............3-19
E
Easy Exit Seat...............................................2-46
Electrical System
Fuses and Circuit Breakers.........................5-105
Power Windows and Other Power
Options.................................................5-105
Windshield Wiper Fuses.............................5-105
Emissions Inspection and Maintenance
Programs...................................................3-42
Engine
Air Cleaner/Filter.........................................5-16
Battery.......................................................5-40
Check and Service Engine Soon Light............3-40
Coolant......................................................5-21
Coolant Heater............................................2-20
Coolant Temperature Gage...........................3-38
5