2008 CHEVROLET EXPRESS PASSANGER engine

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 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, rear
window defogger, climate control fan at high speed,
engine cooling fans, trailer loads, and loads plugged into
accessory power outlets.
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.
Battery Run-Down Protection
This feature shuts off the dome lamps if they are left on
for more than 10 minutes when the ignition is in LOCK.
This will help prevent the battery from running down.
Accessory Power Outlet(s)
Your vehicle may have two accessory power outlets
located on the instrument panel.
To use the outlet lift the cover. The spring cap cover
closes by itself when the outlet is empty.
Certain power accessory plugs may not be compatible
to the accessory power outlet and could result in
blown vehicle or adapter fuses. If you experience a
problem, see your dealer/retailer for additional
information on the accessory power plugs.
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.
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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 is used properly.
There are two modes to clear fog or frost from the
windshield and side windows.
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 in extremely cold conditions. For best results,
clear all snow and ice from the windshield before
defrosting.
Turn the knob on the right of the climate control panel
to select the defog or defrost mode. The temperature
knob should be in the red area and the fan control
toward high.
-(Defog):With this setting, the outside air comes
out of both the floor and defroster outlets. Adjust
the temperature knob for warmer or cooler air. The air
conditioning compressor may operate in this setting
to dehumidify the air.
1(Defrost):This setting operates the defroster.
Most of the air comes out near the windshield,
with some going to the floor outlets and front side
windows. The air conditioning compressor may operate
in this setting to dehumidify the air.Do not drive the vehicle until all the windows are clear.
Rear Window Defogger
Some vehicles may have a rear window defogger.
<(Rear Window Defogger):Press this button to
turn the rear window defogger on or off. Be sure to clear
as much snow from the window as possible.
The rear window defogger uses a warming grid to
remove fog or frost from the rear window and only works
when the ignition is in ON/RUN.
The rear window defogger turns off several minutes
after the button is pressed. If turned on again, the
defogger will run for several more minutes before turning
off. The defogger can also be turned off by pressing
the button again or by turning off the engine.
Notice:Do not use a razor blade or sharp
object to clear the inside rear window. Do not
adhere anything to the defogger grid lines in the
rear glass. These actions may damage the rear
defogger. Repairs would not be covered by
your warranty.
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Warning Lights, Gages, and
Indicators
This part describes the warning lights and gages that
may be on your vehicle. The pictures will help you
locate them.
Warning lights and gages can signal that something is
wrong before it becomes serious enough to cause
an expensive repair or replacement. Paying attention to
your warning lights and gages could also save you
or others from injury.
Warning lights come on when there may be or is a
problem with one of your vehicle’s functions. As you will
see in the details on the next few pages, some
warning lights come on briefly when you start the
engine just to let you know they’re working. If you are
familiar with this section, you should not be alarmed
when this happens.Gages can indicate when there may be or is a
problem with one of your vehicle’s functions. Often
gages and warning lights work together to let you
know when there’s a problem with your vehicle.
When one of the warning lights comes on and stays
on when you are driving, or when one of the gages
shows there may be a problem, check the section
that tells you what to do about it. Please follow
this manual’s advice. Waiting to do repairs can be
costly – and even dangerous. So please get to know
your warning lights and gages. They’re a big help.
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Instrument Panel Cluster
The instrument panel cluster is designed to let you know at a glance how the vehicle is running. You will know how
fast you are going, how much fuel you are using, and many other things you will need to know to drive safely
and economically. If your vehicle has the DURAMAX
®Diesel engine, see the DURAMAX®Diesel manual for more
information.
United States version shown, Canada similar
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Safety Belt Reminders
Safety Belt Reminder Light
When the engine is started, a chime will come on for
several seconds to remind people to fasten their safety
belts, unless the driver’s safety belt is already buckled.
The safety belt light will
also come on and stay on
for several seconds,
then it will flash for
several more.
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 1-69for more information.
The passenger safety belt light, located on the
instrument panel, will come on and stay on for several
seconds and then flash 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.
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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 1-57.
This light will come on
when you start your
vehicle, and it will flash for
a few seconds. The
light should go out and the
system is ready.
If the airbag readiness light stays on after you start the
vehicle or comes on when you are driving, your
airbag system may not work properly. Have your vehicle
serviced right away.{CAUTION:
If the airbag readiness light stays on after you
start your vehicle, it means the airbag system
may not be working properly. The airbags in
your vehicle may not inate in a crash, or they
could even inate without a crash. To help
avoid injury to yourself or others, have your
vehicle serviced right away if the airbag
readiness light stays on after you start your
vehicle.
The airbag readiness light should flash for a few
seconds when you start the engine. If the light does not
come on then, have it fixed immediately. If there is a
problem with the airbag system, an airbag Driver
Information Center (DIC) message may also come on.
SeeDIC Warnings and Messages on page 3-52for
more information.
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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 3-29for more on this, including
important safety information.
Charging System Light
This light will come on
briefly when you turn on
the ignition, 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 you are driving, you may have a
problem with the charging system. A charging system
Driver Information Center (DIC) message may also
appear. SeeDIC Warnings and Messages on page 3-52
for more information. This light could indicate that you
have problems with a generator drive belt, or another
electrical problem. Have it checked right away. If
you must drive a short distance with the light on, be
certain to turn off all your 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 shows
the battery’s state of
charge in DC volts.
When the engine is running, the gage shows the
condition of the charging system. Readings between the
low and high warning zones indicate the normal
operating range.
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 at an idle 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.
Brake System Warning Light
Your vehicle’s hydraulic brake system is divided into
two parts. If one part is not working, the other part can
still work and stop you. For good braking, though,
you need both parts working well.
If the warning light comes on, there could be a brake
problem. Have your brake system inspected right away.
This light should come on briefly when you turn the
ignition key to RUN. If it does not come on then, have it
fixed so it will be ready to warn you if there is a problem.
United StatesCanada
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