2003 GMC ENVOY heater

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 5-27.
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:When adding coolant, it is important that
you use only DEX-COOLž(silicate-free) coolant.
If coolant other than DEX-COOLžis added to
the system, premature engine, heater core or
radiator corrosion may result. In addition, the engine
coolant will require change sooner Ð at 30,000 miles
(50,000 km) or 24 months, whichever occurs ®rst.
Damage caused by the use of coolant other
than DEX-COOL
žis not covered by your new vehicle
warranty.
What to Use
Use a mixture of one-halfclean, drinkable waterand
one-half DEX-COOLžcoolant. If you use this coolant
mixture, you don't need to add anything else.
5-24

{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 wouldn't 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 wouldn't 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 don't
have to add extra inhibitors or additives which claim
to improve the system. These can be harmful.
Checking Coolant
The engine coolant
recovery tank is in the
engine compartment
on the passenger's side of
the vehicle. See
Engine
Compartment Overview on
page 5-12
for more
information on location.
The vehicle must be on a level surface. When your
engine is cold, the coolant level should be at FULL
COLD, or a little higher.
5-25

If No Steam Is Coming From Your
Engine
If you get an engine overheat warning 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.
If you get the overheat warning with no sign of steam,
try this for a minute or so:
1. In heavy traffic, let the engine idle in neutral while
stopped. If it is safe to do so, pull off the road,
shift to PARK (P) or NEUTRAL (N) and let
the engine idle.
2. Turn on your heater to full hot at the highest fan
speed and open the window as necessary.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 and you have not stopped, pull
over, stop, and park your vehicle right away.
If there's still no sign of steam, you can 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.
You may decide not to lift the hood but to get service
help right away.
5-28

The coolant level should
be at least up to 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. Don't touch them. If you
do, you can be burned.
Don't 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 isn't covered by your warranty.
Notice:When adding coolant, it is important that
you use only DEX-COOLž(silicate-free) coolant.
If coolant other than DEX-COOLžis added to
the system, premature engine, heater core or
radiator corrosion may result. In addition, the engine
coolant will require change sooner Ð at 30,000 miles
(50 000 km) or 24 months, whichever occurs ®rst.
Damage caused by the use of coolant other
than DEX-COOL
žis not covered by your new vehicle
warranty.
5-30

How to Add Coolant to the Coolant
Recovery Tank
If you haven't found a problem yet, but the coolant level
isn't at the FULL COLD mark, add a 50/50 mixture of
clean, drinkable waterand DEX-COOLžengine coolant
at the coolant recovery tank. SeeEngine Coolant on
page 5-24for more information.
{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 wouldn't 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. Don't spill coolant on a hot engine.
5-31

Convenience Net............................................2-49
Coolant.........................................................3-41
Engine Temperature Gage............................3-41
Heater, Engine............................................2-22
Cooling System..............................................5-29
Cruise Control Light........................................3-47
Cruise Control................................................3-12
Current and Past Model Order Forms................7-11
Customer Assistance Information........................ 7-7
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....7-10
Reporting Safety Defects to the Canadian
Government.............................................. 7-9
Reporting Safety Defects to the United
States Government.................................... 7-9
Roadside Assistance Program......................... 7-5
Service Publications Ordering Information........7-10
D
Daytime Running Lamps (DRL).........................3-16
Defensive Driving............................................. 4-2
Defogging and Defrosting.........................3-22, 3-27Delayed Locking............................................... 2-9
Dinghy Towing................................................4-46
Doing Your Own Service Work........................... 5-3
Dome Lamp Override......................................3-18
Dome Lamps.................................................3-19
Door............................................................... 2-9
Delayed Locking........................................... 2-9
Locks.......................................................... 2-8
Power Door Locks......................................... 2-9
Programmable Automatic Door Locks.............2-10
Rear Door Security Locks.............................2-12
DRIVER DOOR AJAR.....................................3-62
Driver Information Center (DIC).........................3-50
DIC Operation and Displays..........................3-51
DIC Warnings and Messages........................3-60
Driver............................................................1-14
Position, Safety Belt.....................................1-14
Driving Across an Incline..................................4-24
Driving Downhill..............................................4-23
Driving in Mud, Sand, Snow or Ice....................4-26
Driving in Water..............................................4-27
Driving On Grades..........................................4-58
Driving on Off-Road Hills.................................4-19
Driving on Snow or Ice....................................4-40
Driving Through Deep Standing Water...............4-31
Driving Through Flowing Water.........................4-32
Driving Uphill..................................................4-20
Driving with a Trailer.......................................4-56
Driving..........................................................4-28
At Night.....................................................4-28
4

Driving (cont.)
City...........................................................4-33
Defensive..................................................... 4-2
Drunken....................................................... 4-2
Freeway.....................................................4-34
Hill and Mountain Roads..............................4-37
In Rain and on Wet Roads...........................4-30
Winter........................................................4-39
Dual Automatic Climate Control System.............3-24
Dual Climate Control System............................3-21
DVD Player....................................................3-95
DVD ............................................................3-107
Cleaning the Video Screen..........................3-107
Distortion..................................................3-105
Rear Seat Entertainment System...................3-92
E
Electrical System............................................5-89
Add-On Equipment......................................5-89
Fuses and Circuit Breakers...........................5-90
Headlamps.................................................5-89
Power Windows and Other Power Options......5-90
Windshield Wiper Fuses...............................5-89
Electronically Controlled Air Suspension
System......................................................4-49
Emergency Release for Opening Liftgate............2-13
Emissions Inspection and Maintenance
Programs...................................................3-44Engine Compartment Fuse Block......................5-91
ENGINE COOLANT HOT/IDLE ENGINE.............3-60
Engine Coolant Level Check.............................6-11
Engine Oil Additives........................................5-18
Engine Oil Level Check...................................6-11
Engine Oil Scheduled Maintenance..................... 6-5
Engine..........................................................5-20
Air Cleaner/Filter.........................................5-20
Battery.......................................................5-41
Change Engine Oil Light...............................3-46
Check and Service Engine Soon Light............3-42
Compartment Overview................................5-12
Coolant Heater............................................2-22
Coolant Temperature Gage...........................3-41
Coolant......................................................5-24
Cooling System Inspection............................6-17
Exhaust.....................................................2-33
Fan Noise..................................................5-35
Oil .............................................................5-15
Overheating................................................5-27
Reduced Power Light...................................3-47
Starting......................................................2-21
Entertainment System....................................3-107
Cleaning the Video Screen..........................3-107
DVD Distortion..........................................3-105
Entry Lighting.................................................3-18
Environmental Concerns..................................4-17
Erasing HomeLink
žButtons..............................2-43
Exit Lighting...................................................3-18
Express±Down Window....................................2-16
5

Shifting Out of Park (P)...................................2-31
Skidding........................................................4-14
Snow Plow....................................................4-50
Some Other Rainy Weather Tips.......................4-32
Spare Tire Check............................................6-12
Special Fabric Cleaning Problems.....................5-81
Speci®cations, Capacities...............................5-102
Speedometer..................................................3-36
Stalling on an Incline.......................................4-26
Starter Switch Check.......................................6-13
Starting Your Engine.......................................2-21
Steering in Emergencies..................................4-11
Steering, Suspension and Front Drive Axle Boot
and Seal Inspection.....................................6-16
Steering Tips..................................................4-10
Steering Wheel Climate Controls.......................3-33
Steering Wheel Controls, Audio.......................3-105
Steering........................................................4-10
Stereo RCA Jacks..........................................3-93
Storage Areas................................................2-49
Convenience Net.........................................2-49
Front Storage Area......................................2-45
Glove Box..................................................2-44
Luggage Carrier..........................................2-48
Overhead Console.......................................2-44
Rear Floor Storage Lid.................................2-49
Storing a Flat or Spare Tire and Tools...............5-77
Stuck in Sand, Mud, Ice or Snow......................4-44Sun Visors.....................................................2-16
Sunglasses Storage Compartment.....................2-44
Sunroof.........................................................2-51
T
Tachometer....................................................3-36
Taillamps.......................................................5-51
Turn Signal Lamps......................................5-51
Testing the Alarm............................................2-18
Theft-Deterrent, Radio....................................3-104
Theft-Deterrent Systems...................................2-17
Content Theft-Deterrent................................2-17
Passlock
ž...................................................2-18
Tilt Wheel........................................................ 3-7
Tire In¯ation Check.........................................6-11
Tires.............................................................5-54
Buying New Tires........................................5-58
Chains.......................................................5-62
Changing a Flat Tire....................................5-64
If a Tire Goes Flat.......................................5-64
In¯ation -- Tire Pressure...............................5-55
Inspection and Rotation................................5-55
Uniform Tire Quality Grading.........................5-59
Wheel Alignment and Tire Balance.................5-60
Wheel Replacement.....................................5-60
When It Is Time for New Tires......................5-57
To Use the Engine Coolant Heater....................2-22
14