2008 GMC ENVOY Coolant system

Keys...............................................................2-3
Remote Keyless Entry (RKE) System................2-4
Remote Keyless Entry (RKE) System
Operation...................................................2-5
Doors and Locks.............................................2-7
Door Locks....................................................2-7
Power Door Locks..........................................2-8
Delayed Locking.............................................2-8
Programmable Automatic Door Locks................2-9
Rear Door Security Locks..............................2-11
Lockout Protection........................................2-11
Liftgate/Liftglass............................................2-12
Windows........................................................2-13
Power Windows............................................2-14
Sun Visors...................................................2-15
Theft-Deterrent Systems..................................2-16
Content Theft-Deterrent.................................2-16
Passlock
®(U. S. Only)..................................2-17
PASS-Key®III+............................................2-18
PASS-Key®III+ Operation (Canada Only).........2-18
Starting and Operating Your Vehicle................2-20
New Vehicle Break-In....................................2-20
Ignition Positions..........................................2-21Retained Accessory Power (RAP)...................2-22
Starting the Engine.......................................2-22
Adjustable Throttle and Brake Pedal................2-24
Engine Coolant Heater..................................2-24
Active Fuel Management™.............................2-25
Automatic Transmission Operation...................2-26
Four-Wheel Drive..........................................2-29
Parking Brake..............................................2-33
Shifting Into PARK (P)...................................2-34
Shifting Out of PARK (P)...............................2-36
Parking Over Things That Burn.......................2-37
Engine Exhaust............................................2-37
Running the Vehicle While Parked..................2-38
Mirrors...........................................................2-39
Manual Rearview Mirror.................................2-39
Manual Rearview Mirror with OnStar
®..............2-39
Automatic Dimming Rearview Mirror with
OnStar
®and Compass...............................2-39
Automatic Dimming Rearview Mirror with
OnStar
®, Compass and Temperature
Display....................................................2-41
Automatic Dimming Rearview Mirror with
Compass and Temperature Display..............2-44
Section 2 Features and Controls
2-1

{CAUTION:
Plugging the cord into an ungrounded outlet
could cause an electrical shock. Also, the
wrong kind of extension cord could overheat
and cause a re. You could be seriously
injured. Plug the cord into a properly grounded
three-prong 110-volt AC outlet. If the cord will
not reach, use a heavy-duty three-prong
extension cord rated for at least 15 amps.
4. Before starting the engine, be sure to unplug and
store the cord as it was before to keep it away
from moving engine parts. If you do not, it could
be damaged.
How long should you keep the coolant heater plugged in?
The answer depends on the outside temperature, the
kind of oil you have, and some other things. Instead of
trying to list everything here, we ask that you contact your
dealer in the area where you will be parking your vehicle.
The dealer/retailer can give you the best advice for that
particular area.
Active Fuel Management™
Your vehicle’s V8 engine may have Active Fuel
Management™. This system allows the engine to
operate on either all or half of its cylinders, depending
on your driving conditions.
When less power is required, such as cruising at a
constant vehicle speed, the system will operate in the
half cylinder mode, allowing your vehicle to achieve
better fuel economy. When greater power demands are
required, such as accelerating from a stop, passing,
or merging onto a freeway, the system will maintain
full-cylinder operation.
2-25

Instrument Panel Overview...............................3-4
Hazard Warning Flashers................................3-6
Other Warning Devices...................................3-6
Horn.............................................................3-6
Tilt Wheel.....................................................3-6
Turn Signal/Multifunction Lever.........................3-7
Turn and Lane-Change Signals........................3-7
Headlamp High/Low-Beam Changer..................3-8
Flash-to-Pass.................................................3-8
Windshield Wipers..........................................3-9
Windshield Washer.........................................3-9
Rear Window Wiper/Washer...........................3-10
Headlamp Washer........................................3-11
Cruise Control..............................................3-11
Headlamps..................................................3-14
Headlamps on Reminder................................3-15
Daytime Running Lamps (DRL).......................3-15
Automatic Headlamp System..........................3-15
Fog Lamps..................................................3-16
Instrument Panel Brightness...........................3-17
Dome Lamps...............................................3-17
Dome Lamp Override....................................3-17
Entry Lighting...............................................3-18
Exit Lighting.................................................3-18
Reading Lamps............................................3-18
Electric Power Management...........................3-18
Battery Run-Down Protection..........................3-19Accessory Power Outlet(s).............................3-20
Ashtray(s) and Cigarette Lighter......................3-20
Climate Controls............................................3-21
Dual Climate Control System..........................3-21
Dual Automatic Climate Control System...........3-23
Outlet Adjustment.........................................3-28
Rear Climate Control System.........................3-28
Warning Lights, Gages, and Indicators............3-30
Instrument Panel Cluster................................3-31
Speedometer and Odometer...........................3-32
Trip Odometer..............................................3-32
Tachometer.................................................3-32
Safety Belt Reminders...................................3-32
Airbag Readiness Light..................................3-33
Passenger Airbag Status Indicator...................3-34
Charging System Light..................................3-36
Voltmeter Gage............................................3-37
Brake System Warning Light..........................3-38
Antilock Brake System Warning Light...............3-39
StabiliTrak
®Service Light...............................3-39
StabiliTrak®Indicator Light..............................3-40
Engine Coolant Temperature Gage..................3-40
Tire Pressure Light.......................................3-41
Malfunction Indicator Lamp.............................3-41
Oil Pressure Gage........................................3-44
Change Engine Oil Light................................3-45
Section 3 Instrument Panel
3-1

Driver’s Side Temperature Lever:The lever on the
left side of the climate control panel is used to raise
or lower the temperature on the driver’s side of
the vehicle. Slide the lever up or down to adjust
the temperature.
Passenger’s Side Temperature Lever:The lever on
the right side of the climate control panel is used to raise
or lower the temperature on the passenger’s side of
the vehicle. Slide the lever up or down to adjust the
temperature. This lever also adjusts the temperature
to the rear seat outlets.
When the temperature outside is 0°F (−18°C) or lower,
use the engine coolant heater, if the vehicle has
one, to provide warmer air, faster to your vehicle.
#(Air Conditioning):Press this button to turn the
air-conditioning system on or off. When the button is
pressed, an indicator light will come on and the system
will begin to cool and dehumidify the air inside of the
vehicle. You may notice a slight change in engine
performance when the air conditioning compressor
shuts off and turns on again. This is normal.
Defogging and Defrosting
Fog on the inside of windows is a result of high humidity
(moisture) condensing on the cool window glass. This
can be minimized if the climate control system is used
properly. There are two modes to choose from to clear
fog or frost from your windshield. Use the defog mode
to clear the windows of fog or moisture and warm the
passengers. Use the defrost mode to remove fog or
frost from the windshield more quickly.
Turn the right knob clockwise or counterclockwise to
select one of the following modes:
-(Defog):This mode directs the air to the
oor outlets, windshield and side window outlets.
The recirculation button cannot be selected while in
defog mode.
1(Defrost):This mode directs most of the air to the
windshield and the side window outlets, with only a little
air directed to the oor outlets. The air conditioning
compressor may run to dehumidify the air to prevent
window fogging. The recirculation button cannot be
selected while in defrost mode. Do not drive the vehicle
until all the windows are clear.
3-22

StabiliTrak®Indicator Light
This warning light should
come on briey when the
engine is started.
During most driving conditions, this light will not come
on. If the StabiliTrak
®System is actively controlling
the stability and/or traction of the vehicle, this light
will ash. This is normal.
This light will come on if any portion of the system
has been manually turned off or a problem is detected
in the system.
If your vehicle has a Driver Information Center, a
message will appear also, seeDIC Warnings and
Messages on page 3-53andStabiliTrak
®System on
page 4-6for more information.
Engine Coolant Temperature Gage
This gage shows the engine coolant temperature.
If the gage pointer moves into the red area, it means that
the engine coolant has overheated. If you have been
operating your vehicle under normal driving conditions,
you should pull off the road, stop your vehicle and turn off
the engine as soon as possible.
SeeEngine Overheating on page 5-28for more
information.
United StatesCanada
3-40

Highbeam On Light
This light comes on when
the high-beam headlamps
are in use.
SeeHeadlamp High/Low-Beam Changer on page 3-8
for more information.
Service Four-Wheel Drive Warning
Light
This light should come on
briey when you turn on
the ignition, as a check to
show you it is working.The service four-wheel drive light comes on to indicate
that there may be a problem with the drive system
and service is required. Malfunctions can be indicated
by the system before any problem is apparent,
which may prevent serious damage to the vehicle.
This system is also designed to assist your dealer
in correctly diagnosing a malfunction.
Check Gages Warning Light
The check gages light will
come on briey when you
are starting the engine.
If the light comes on and stays on while you are
driving, check your coolant temperature and engine
oil pressure gages to see if they are in the warning
zones.
3-47

CHECK TIRE PRESSURE
This message displays when the pressure in one or
more of the vehicle’s tires needs to be checked. If a tire
pressure message appears on the DIC, stop as soon
as you can. Have the tire pressures checked and set to
those shown on the Tire Loading Information label.
SeeTires on page 5-57,Loading Your Vehicle on
page 4-34, andInflation - Tire Pressure on page 5-64.
The DIC also shows the tire pressure values. See
DIC Operation and Displays on page 3-50. If the tire
pressure is low, the low tire pressure warning light
comes on. SeeTire Pressure Light on page 3-41.
CHECK WASHER FLUID
This message displays if the washer uid level is low.
Adding washer uid to the windshield washer uid
reservoir clears this message. SeeWindshield Washer
Fluid on page 5-37. This message clears itself after
10 seconds, or you can manually clear it from the
DIC display.
CURB VIEW ACTIVATED
This message displays when the passenger outside
rearview mirror moves into the curb view position.
SeeOutside Curb View Assist Mirror on page 2-47
for more information.
DRIVER DOOR AJAR
This message displays and a chime sounds if the driver
door is not fully closed. Stop and turn off the vehicle,
check the door for obstructions, and close the door again.
Check to see if the message still appears on the DIC.
ENGINE COOLANT HOT/ENGINE
OVERHEATED
Notice:If you drive your vehicle while the engine
is overheating, severe engine damage may occur.
If an overheat warning appears on the instrument
panel cluster and/or DIC, stop the vehicle as soon as
possible. Do not increase the engine speed above
normal idling speed. SeeEngine Overheating
on page 5-28for more information.
This message displays and a chime sounds if the
cooling system temperature gets hot. SeeEngine
Overheating on page 5-28for the proper course of
action. This message clears when the coolant
temperature drops to a safe operating temperature.
FUEL LEVEL LOW
This message displays and a chime sounds if the fuel
level is low. Refuel as soon as possible. SeeLow
Fuel Warning Light on page 3-49,Filling the Tank on
page 5-8, andFuel on page 5-5for more information.
3-54

Service............................................................5-3
Accessories and Modications..........................5-3
California Proposition 65 Warning.....................5-4
California Perchlorate Materials Requirements.....5-4
Doing Your Own Service Work.........................5-4
Adding Equipment to the Outside of
Your Vehicle..............................................5-5
Fuel................................................................5-5
Gasoline Octane............................................5-6
Gasoline Specications....................................5-6
California Fuel...............................................5-6
Additives.......................................................5-7
Fuels in Foreign Countries...............................5-7
Filling the Tank..............................................5-8
Filling a Portable Fuel Container.....................5-10
Checking Things Under the Hood....................5-10
Hood Release..............................................5-11
Engine Compartment Overview.......................5-12
Engine Oil...................................................5-16
Engine Oil Life System..................................5-19
Engine Air Cleaner/Filter................................5-21
Automatic Transmission Fluid.........................5-23
Engine Coolant.............................................5-26
Radiator Pressure Cap..................................5-28
Engine Overheating.......................................5-28
Cooling System............................................5-30Engine Fan Noise.........................................5-35
Power Steering Fluid.....................................5-36
Windshield Washer Fluid................................5-37
Brakes........................................................5-38
Battery........................................................5-41
Jump Starting...............................................5-42
Rear Axle.......................................................5-46
Four-Wheel Drive............................................5-47
Front Axle......................................................5-48
Headlamp Aiming...........................................5-49
Bulb Replacement..........................................5-49
Halogen Bulbs..............................................5-49
Headlamps..................................................5-50
Front Turn Signal, Sidemarker and
Parking Lamps..........................................5-51
Taillamps, Turn Signal, and Stoplamps............5-51
Back-Up Lamps............................................5-53
License Plate Lamp......................................5-53
Replacement Bulbs.......................................5-54
Windshield Wiper Blade Replacement..............5-54
Tires..............................................................5-57
Tire Sidewall Labeling...................................5-58
Tire Terminology and Denitions.....................5-61
Ination - Tire Pressure.................................5-64
Section 5 Service and Appearance Care
5-1