2008 GMC ENVOY electrical

Entry Lighting
The vehicle has entry lighting.
When any door is opened, the dome lamps come on as
long as the dome override lamp override button is not
pressed in. When all the doors are closed, the lamps
stay on for a short period of time and then turn off
automatically. If you use the Remote Keyless Entry (RKE)
transmitter to unlock the vehicle, the interior lamps come
on for a short time whether or not the dome lamp override
is on.
Exit Lighting
With exit lighting, the interior lamps come on when you
remove the key from the ignition. If the dome override
is off, these lamps stay on for a short period of time
and then go out.
Reading Lamps
The reading lamps are located in the front console.
Press the lens on the lamps to turn the reading lamps
on or off.
Electric Power Management
The vehicle has Electric Power Management (EPM)
that estimates the battery’s temperature and state
of charge. It then adjusts the voltage for best
performance and extended life of the battery.
When the battery’s state of charge is low, the voltage is
raised slightly to quickly put the charge back in. When
the state of charge is high, the voltage is lowered slightly
to prevent overcharging. If the vehicle has a voltmeter
gage or a voltage display on the Driver Information
Center (DIC), you may see the voltage move up
or down. This is normal. If there is a problem, an
alert will be displayed.
The battery can be discharged at idle if the electrical
loads are very high. This is true for all vehicles. This is
because the generator (alternator) may not be spinning
fast enough at idle to produce all the power that is
needed for very high electrical loads.
A high electrical load occurs when several of the
following loads are on: headlamps, high beams, fog
lamps, rear window defogger, climate control fan at
high speed, heated seats, engine cooling fans, trailer
loads, and loads plugged into accessory power outlets.
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EPM works to prevent excessive discharge of the
battery. It does this by balancing the generator’s output
and the vehicle’s electrical needs. It can increase
engine idle speed to generate more power, whenever
needed. It can temporarily reduce the power demands
of some accessories.
Normally, these actions occur in steps or levels, without
being noticeable. In rare cases at the highest levels of
corrective action, this action may be noticeable to the
driver. If so, a Driver Information Center (DIC) message
might be displayed, such as Battery Saver Active or
Service Battery Charging System. If this message is
displayed, it is recommended that the driver reduce the
electrical loads as much as possible. SeeDIC Warnings
and Messages on page 3-53.Battery Run-Down Protection
This feature shuts off the dome, courtesy, and vanity
lamps if they are left on for more than 20 minutes
when the ignition is off. This will keep the battery
from running down.
If the battery run-down protection shuts off the interior
lamps, it may be necessary to do one of the following to
return to normal operation:
Shut off all lamps and close all doors.
Turn the ignition key to RUN.
This feature will also turn off the parking lamps and
headlamps under most circumstances, if they are left on.
If you would like to turn them back on, turn the exterior
lamps knob.
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Accessory Power Outlet(s)
With the accessory power outlets, you can plug in
auxiliary electrical equipment such as a cellular
telephone or CB radio.
Your vehicle has three accessory power outlets.
There are two outlets located below the climate
controls and one outlet is on the rear of the center
oor console.
Remove the cover from the outlet to use the outlet.
Be sure to put the cover back on when not using the
accessory power outlet.
Certain electrical accessories may not be compatible
with the accessory power outlet and could result
in blown vehicle or adaptor fuses. If you experience
a problem, see your dealer for additional information
on the accessory power outlets.
Notice:Adding any electrical equipment to your
vehicle may damage it or keep other components
from working as they should. The repairs would not
be covered by your warranty. Do not use equipment
exceeding maximum amperage rating of 20 amperes.
Check with your dealer/retailer before adding
electrical equipment.
When adding electrical equipment, be sure to follow
the proper installation instructions included with the
equipment.Notice:Improper use of the power outlet can cause
damage not covered by your warranty. Do not
hang any type of accessory or accessory bracket
from the plug because the power outlets are
designed for accessory power plugs only.
Ashtray(s) and Cigarette Lighter
Your vehicle may have this feature. The ashtray is
removable and ts into the front cupholder.
Notice:If you put papers, pins, or other ammable
items in the ashtray, hot cigarettes or other smoking
materials could ignite them and possibly damage
your vehicle. Never put ammable items in the
ashtray.
To remove the ashtray, pull the covered bin out of the
cupholder.
To use the lighter, press it in all the way, and let go.
When it is ready, it will pop back out by itself.
Notice:Holding a cigarette lighter in while it is
heating will not allow the lighter to back away from
the heating element when it is hot. Damage from
overheating may occur to the lighter or heating
element, or a fuse could be blown. Do not hold a
cigarette lighter in while it is heating. Do not use
equipment exceeding maximum amperage rating
of 20 amperes.
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This chime and light is repeated if the driver remains
unbuckled and the vehicle is in motion. If the driver’s belt
is already buckled, neither the chime nor the light will
come on.
Passenger Safety Belt Reminder Light
Several seconds after the engine is started, a chime will
sound for several seconds to remind the front passenger
to buckle their safety belt. This would only occur if the
passenger airbag is enabled. SeePassenger Sensing
System on page 1-61for more information. The
passenger safety belt light, located on the instrument
panel, will come on and stay on for several seconds and
then ash for several more.
This chime and light are
repeated if the passenger
remains unbuckled and
the vehicle is in motion.
If the passenger’s safety belt is buckled, neither the
chime nor the light will come on.
Airbag Readiness Light
There is an airbag readiness light on the instrument panel
cluster, which shows the airbag symbol. The system
checks the airbag’s electrical system for malfunctions.
The light tells you if there is an electrical problem.
The system check includes the airbag sensor, the
pretensioners, the airbag modules, the wiring and
the crash sensing and diagnostic module. For more
information on the airbag system, seeAirbag System
on page 1-53.
This light will come on
when you start your
vehicle, and it will ash
for a few seconds. The
light should go out and
the system is ready.
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If, after several seconds, both status indicator lights
remain on, or if there are no lights at all, there may
be a problem with the lights or the passenger sensing
system. See your dealer/retailer for service.
{CAUTION:
If the airbag readiness light in the instrument
panel cluster ever comes on and stays on,
it means that something may be wrong with
the airbag system. If this ever happens, have
the vehicle serviced promptly, because an
adult-size person sitting in the right front
passenger’s seat may not have the protection
of the airbag(s). SeeAirbag Readiness Light
on page 3-33for more on this, including
important safety information.
Charging System Light
This light will come on
briey when you turn on the
ignition key, but the engine
is not running, as a check
to show you it is working.
It should go out once the engine is running. If it stays
on, or comes on while driving, there could be a problem
with the charging system. A charging system Driver
Information Center (DIC) message may also appear.
SeeDIC Warnings and Messages on page 3-53for
more information. This light could indicate that there
are problems with a generator drive belt, or that there is
an electrical problem. Have it checked right away. If you
must drive a short distance with the light on, be certain
to turn off all the accessories, such as the radio and air
conditioner.
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Voltmeter Gage
When your engine is not
running, but the ignition is
on, this gage displays the
battery voltage in DC volts.
When the engine is running, the gage shows the
condition of the charging system. The gage may
transition from a higher to lower or a lower to higher
reading, this is normal. Readings between the low
and high warning zones indicate the normal operating
range. The voltmeter gage may also read lower when
in fuel economy mode. This is normal.Readings in the low warning zone may occur when a
large number of electrical accessories are operating
in the vehicle and the engine is left idling for an
extended period. This condition is normal since the
charging system is not able to provide full power
at engine idle. As engine speeds are increased, this
condition should correct itself as higher engine speeds
allow the charging system to create maximum power.
You can only drive for a short time with the reading
in either warning zone. If you must drive, turn off
all unnecessary accessories.
Readings in either warning zone indicate a possible
problem in the electrical system. Have the vehicle
serviced as soon as possible.
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If the Light is Flashing
The following can prevent more serious damage to your
vehicle:
Reduce vehicle speed.
Avoid hard accelerations.
Avoid steep uphill grades.
If you are towing a trailer, reduce the amount of
cargo being hauled as soon as it is possible.
If the light stops ashing and remains on steady,
see “If the Light Is On Steady” following.
If the light continues to ash, when it is safe to do so,
stop the vehicle. Find a safe place to park the vehicle.
Turn the ignition off, wait at least 10 seconds, and restart
the engine. If the light remains on steady, see “If the
Light Is On Steady” following. If the light is still ashing,
follow the previous steps and see your dealer/retailer
for service as soon as possible.
If the Light Is On Steady
You might be able to correct the emission system
malfunction by considering the following:
Did you recently put fuel into your vehicle?
If so, reinstall the fuel cap, making sure to fully install
the cap. SeeFilling the Tank on page 5-8. The diagnostic
system can determine if the fuel cap has been left off orimproperly installed. A loose or missing fuel cap allows
fuel to evaporate into the atmosphere. A few driving trips
with the cap properly installed should turn the light off.
Did you just drive through a deep puddle of water?
If so, your vehicle’s electrical system might be wet.
The condition is usually corrected when the electrical
system dries out. A few driving trips should turn the
light off.
Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel. See
Gasoline Octane on page 5-6. Poor fuel quality causes
the engine not to run as efficiently as designed. You
might notice this as stalling after start-up, stalling when
you put the vehicle into gear, misring, hesitation on
acceleration, or stumbling on acceleration — these
conditions might go away once the engine is warmed up.
This will be detected by the system and cause the light to
turn on.
If you experience one or more of these conditions,
change the fuel brand you use. It will require at least
one full tank of the proper fuel to turn the light off.
If none of the above steps have made the light turn
off, your dealer/retailer can check the vehicle. Your
dealer/retailer has the proper test equipment and
diagnostic tools to x any mechanical or electrical
problems that might have developed.
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REAR ACCESS OPEN
This message displays and a chime sounds if the
liftgate or liftglass is open while the ignition is in
ON/RUN. Turn off the vehicle and check the liftgate
and liftglass. SeeLiftgate/Liftglass on page 2-12.
Restart the vehicle and check for the message on
the DIC display.
RIGHT REAR DOOR AJAR
This message displays and a chime sounds if the
passenger side rear 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.
SERVICE AIR BAG
This message displays if there is a problem with
the airbag system. Have your dealer/retailer inspect
the system for problems. SeeAirbag Readiness Light
on page 3-33andAirbag System on page 1-53for
more information.
SERVICE BRAKE SYSTEM
This message displays if a problem occurs with the
brake system. If this message appears, stop as soon as
possible and turn off the vehicle. Restart the vehicleand check for the message on the DIC display. If the
message is still displayed, or appears again when
you begin driving, the brake system needs service.
See your dealer/retailer.
SERVICE CHARGING SYS (System)
This message displays if there is a problem with the
battery charging system. Under certain conditions, the
charging system light may also turn on in the instrument
panel cluster. SeeCharging System Light on page 3-36.
The battery will not be charging at an optimal rate and
the vehicle will lose the ability to enter the fuel economy
mode. The vehicle is safe to drive, however you should
have the electrical system checked by your
dealer/retailer.
SERVICE STABILITRAK
If this message displays, it means there may be a
problem with the StabiliTrak®system. If this message
appears, try to reset the system by performing the
following: stop; turn off the engine; then start the engine
again. If this message still comes on, it means there is a
problem. You should see your dealer/retailer for service.
The vehicle is safe to drive, however, you do not have the
benet of StabiliTrak
®, so reduce your speed and drive
accordingly.
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