2009 GMC ENVOY heater

What to Use
{CAUTION:
Adding only plain water to the cooling system can
be dangerous. Plain water, or some other liquid
such as alcohol, can boil before the proper coolant
mixture will. The vehicle’s coolant warning system
is set for the proper coolant mixture. With plain
water or the wrong mixture, the engine could
get too hot but you would not get the overheat
warning. The engine could catch re and you or
others could be burned. Use a 50/50 mixture of
clean, drinkable water and DEX-COOL
®coolant.Use a 50/50 mixture of clean, drinkable water and
DEX-COOL coolant. If using this mixture, nothing else
needs to be added. This mixture:
Gives freezing protection down to−34°F (−37°C),
outside temperature.
Gives boiling protection up to 265°F (129°C),
engine temperature.
Protects against rust and corrosion.
Will not damage aluminum parts.
Helps keep the proper engine temperature.
Notice:If an improper coolant mixture is used,
the engine could overheat and be badly damaged.
The repair cost would not be covered by the vehicle
warranty. Too much water in the mixture can freeze
and crack the engine, radiator, heater core, and other
parts.
Notice:If extra inhibitors and/or additives are used
in the vehicle’s cooling system, the vehicle could be
damaged. Use only the proper mixture of the engine
coolant listed in this manual for the cooling system.
SeeRecommended Fluids and Lubricants on
page 6-12for more information.
5-26

If No Steam Is Coming From The
Engine Compartment
If an engine overheat warning is displayed but no steam
can be seen or heard, the problem may not be too
serious. Sometimes the engine can get a little too hot
when the vehicle:
Climbs a long hill on a hot day.
Stops after high-speed driving.
Idles for long periods in traffic.
Tows a trailer.
If the overheat warning is displayed with no sign of steam:
1. Turn the air conditioning off.
2. Turn the heater on to the highest temperature and
to the highest fan speed. Open the windows as
necessary.
3. In heavy traffic, let the engine idle in N (Neutral)
while stopped. If it is safe to do so, pull off the
road, shift to P (Park) or N (Neutral) and let
the engine idle.
If the temperature overheat gage is no longer in the
overheat zone or an overheat warning no longer
displays, the vehicle can be driven. Continue to drivethe vehicle slow for about 10 minutes. Keep a safe
vehicle distance from the car in front of you. If the
warning does not come back on, continue to drive
normally.
If the warning continues, pull over, stop, and park the
vehicle right away.
If there is no sign of steam, idle the engine for three
minutes while parked. If the warning is still displayed,
turn off the engine until it cools down.Engine Fan Noise
The vehicle has a clutched engine cooling fan. When the
clutch is engaged, the fan spins faster to provide more air
to cool the engine. In most everyday driving conditions
the clutch is not engaged. This improves fuel economy
and reduces fan noise. Under heavy vehicle loading,
trailer towing, and/or high outside temperatures, the fan
speed increases when the clutch engages so you may
hear an increase in fan noise. This is normal and should
not be mistaken as the transmission slipping or making
extra shifts. It is merely the cooling system functioning
properly. The fan will slow down when additional cooling
is not required and the clutch disengages.
You may also hear this fan noise when the engine is
started. The sound will go away as the fan clutch
disengages.
5-32

Electronic Immobilizer
PASS-Key®III+...........................................2-18
Electronic Immobilizer Operation
PASS-Key
®III+...........................................2-18
Electronically Controlled Air Suspension
System......................................................4-45
Engine
Air Cleaner/Filter.........................................5-20
Change Engine Oil Light...............................3-43
Check and Service Engine Soon Lamp...........3-38
Coolant......................................................5-25
Coolant Heater............................................2-24
Coolant Temperature Gage...........................3-37
Drive Belt Routing.......................................6-15
Engine Compartment Overview......................5-12
Exhaust.....................................................2-37
Fan Noise..................................................5-32
Oil .............................................................5-15
Oil Life System...........................................5-18
Overheating................................................5-30
Reduced Power Light...................................3-44
Starting......................................................2-22
Entry Lighting.................................................3-16
Event Data Recorders.....................................7-17
Exit Lighting...................................................3-17
Extender, Safety Belt.......................................1-32
F
Filter
Engine Air Cleaner......................................5-20
Finish Damage.............................................5-110
Fixed Mast Antenna.......................................3-112
Flashers, Hazard Warning.................................. 3-6
Flash-to-Pass................................................... 3-8
Flat Tire........................................................5-76
Flat Tire, Changing.........................................5-88
Flat Tire, Storing...........................................5-100
Fluid
Automatic Transmission................................5-21
Power Steering...........................................5-33
Windshield Washer......................................5-34
Fog Lamp
Fog ...........................................................3-15
Four-Wheel Drive....................................2-28, 5-44
Front Axle......................................................5-44
Fuel............................................................... 5-5
Additives...................................................... 5-6
California Fuel.............................................. 5-6
Check Gas Cap Light...................................3-47
Driving for Better Economy............................. 4-2
Filling a Portable Fuel Container....................5-10
Filling the Tank............................................. 5-8
Fuels in Foreign Countries.............................. 5-7
5

Fuel (cont.)
Gage .........................................................3-46
Gasoline Octane........................................... 5-5
Gasoline Specications.................................. 5-6
Low Warning Light.......................................3-47
Fuses
Engine Compartment Fuse Block.................5-113
Fuses and Circuit Breakers.........................5-113
Rear Underseat Fuse Block.........................5-116
Windshield Wiper.......................................5-112
G
Gage
Check Gages Warning Light..........................3-45
Engine Coolant Temperature.........................3-37
Fuel..........................................................3-46
Oil Pressure...............................................3-42
Speedometer..............................................3-29
Tachometer.................................................3-29
Voltmeter Gage...........................................3-34
Garage Door Opener.......................................2-46
Gasoline
Octane........................................................ 5-5
Specications............................................... 5-6
Gate Ajar Light...............................................3-45
Glove Box.....................................................2-51
GM Mobility Reimbursement Program.................. 7-7
H
Hazard Warning Flashers................................... 3-6
Head Restraints..............................................1-10
Headlamp
Aiming .......................................................5-45
Headlamps............................................3-13, 5-46
Bulb Replacement.......................................5-46
Daytime Running Lamp................................3-14
Electrical System.......................................5-112
Flash-to-Pass............................................... 3-8
Front Turn Signal, Sidemarker and
Parking Lamps.........................................5-47
Halogen Bulbs............................................5-46
High/Low Beam Changer................................ 3-8
On Reminder..............................................3-14
Washer......................................................3-10
Heated Seats................................................... 1-4
Heater...........................................................3-19
Engine Coolant...........................................2-24
Heater...........................................................3-22
Highbeam On Light.........................................3-44
High-Speed Operation, Tires.............................5-62
Highway Hypnosis...........................................4-26
Hill and Mountain Roads..................................4-27
Hood
Checking Things Under................................5-10
Release.....................................................5-11
Horn ............................................................... 3-6
How to Wear Safety Belts Properly...................1-18
6