1998 CHEVROLET EXPRESS service

Downloaded from www.Manualslib.com manuals search engine The DRL system will make your headlamps come on at
a reduced brightness when:
0 The ignition is on,
0 The headlamp switch is off, and
The parking brake is released.
When the DRL are on, only your headlamps will be on.
The taillamps, sidemarker and other lamps won’t be on.
Your instrument panel won’t be lit up either.
When it begins to get dark, your
DRL indicator light is
a reminder to turn y,our headlamp switch on. The other
lamps that come
on with your headlamps will also
come on.
When you turn off the headlamp switch, the regular
lamps will go off, and your headlamps will change to
the reduced brightness of DRL.
To idle your vehicle with the engine on and the DRL off,
set the parking brake. The DRL will stay off until you
release
the parking brake.
As with any vehicle, you should turn on the regular
headlamp system when you need
it.
Center High-Mounted Stoplamp
Your vehicle’s center high-mounted stoplamp is located
above the rear doors at the center
of the vehicle.
If items are loaded
on the roof of the vehicle, as in a
luggage carrier, care should be taken not
to block or
damage the center high-mounted stoplamp unit.
If you tow a trailer that is equipped with provisions for
a
center high-mounted stoplamp, see your GM dealer for
instructions
on how to make it operate with your
vehicle’s electrical system. As with any electrical system
modification, have the work performed
by a qualified
electrical service person.
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Downloaded from www.Manualslib.com manuals search engine Air Bag Readiness Light
There is an air bag readiness light on the instrument
panel, which shows AIR BAG. The system checks the
air bag’s electrical system for malfunctions. The light
tells you if there is an electrical problem. The system
check includes the air bag sensor, the air bag modules,
the wiring and the crash sensing and diagnostic module.
For more information on the air bag system, see “Air
Bag” in the Index.
AIR
BAG
This light will come on
when you start your engine,
and it will flash for a few
seconds. Then the light
should
go out. This means
the system is ready.
If
the air bag readiness light stays on after you start the
engine or comes on when you are driving, your air bag
system may not work properly. Have your vehicle
serviced right away. The
air bag readiness light should flash for
a few
seconds
when you turn the ignition key to RUN. If the
light doesn’t come on then, have it fixed
so it will be
ready to warn you if there is a problem.
Charging System Light
This light should come on
briefly
when you turn on the
ignition, before starting the
engine,
as a check to show
you it is working.
After the engine starts, the light should
go out. If it stays
on or comes on while you are driving, you may have a
problem with your charging system. It could indicate a
problem with the alternator drive belt, or some other
charging system problem. Have it checked right away.
Driving while this light is on could drain your battery.
If you must drive a short distance with this light
on, it
helps to turn off all your accessories, such as the radio
and air conditioner.
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Downloaded from www.Manualslib.com manuals search engine Voltmeter
1 VOLTS I
W
When your engine is not
running, but
the ignition is
on (in the RUN position),
this gage shows your
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.
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Downloaded from www.Manualslib.com manuals search engine Brake System Warning Light This iiiht should come on briefly when you turn the
When the ignition
is on, the brake system warning light fixed so it will be ready to warn you if a problem.
will come
on when you set your parking brake. The light
will stay on if your parking brake doesn’t release fully.
If the light comes on while you are driving, pull off the
If it stays on after your parking brake is fully released, it road and stop Carefully. YOU may notice that the Pedal is
ignition key
to RUN. If it doesn’t come on then, have it
means you have a brake problem.
Your vehicle’s hydraulic brake system
is divided into
two parts.
If one part isn’t 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.
BRAKE
United States Canada
harder to push. Or, the pedal may go closer to the floor.
It may take longer to stop. If the light is still on, have the
vehicle towed for service. (See “Towing Your Vehicle”
in the Index.)
I-
Your brake system may not be working properly
if the brake system warning light
is on. Driving
with the brake system warning light on can lead
to an accident.
If the light is still on after you’ve
pulled
off the road and stopped carefully, have
the vehicle towed for service.
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Downloaded from www.Manualslib.com manuals search engine Anti-Lock Brake System Warning Light
ANTI -
LOCK
United States Canada
With the anti-lock brake system, this light will come on
when you start your engine and may stay on for several
seconds. That’s normal.
If the light stays
on, or comes on when you’re driving,
your vehicle needs service. If the regular brake system
warning light isn’t
on, you still have brakes, but you
don’t have anti-lock brakes. If the regular brake system
warning light is also on, you don’t have anti-lock brakes
and there’s a problem with your regular brakes. See
“Brake System Warning Light” earlier in this section.
The anti-lock brake system warning light should come
on briefly when
you turn the ignition key to RUN. If the
light doesn’t come on then, have it fixed
so it will be
ready
to warn you if there is a problem.
Engine Coolant Temperature (I ~ - -:
This gage shows the engine
coolant temperature. If the
gage pointer moves into
the red area your engine is
too hot!
It means that your engine coolant has overheated. If
you have been operating your vehicle under normal
operating conditions,
you should pull off the road, stop
your vehicle, and turn
off the ‘engine as soon as possible.
The “Problems on the Road” section
of this
manual shows what to do. See “Engine Overheating”
in the Index.
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Downloaded from www.Manualslib.com manuals search engine Malfunction Indicator Lamp (Service Engine Soon Light) (Gasoline Engine)
81 Your vehicle is equipped
SERVICE
ENGINE
I
SOON
with a computer which
monitors operation
of the
fuel, ignition and emission
control systems.
This system is called OBD I1 (On-Board
Diagnostics-Second Generation) and
is intended to
assure that emissions
are at acceptable levels for the life
of the vehicle, helping
to produce a cleaner
environment. The
SERVICE ENGINE SOON light
comes on to indicate that there
is a problem and service
is required. Malfunctions often will be indicated by the
system before any problem is apparent. This may
prevent more serious damage to your vehicle. This
system
is also designed to assist your service technician
in correctly diagnosing any malfunction.
NOTICE:
If you keep driving your vehicle with this light
on, after a while, your emission controls may not
work as well, your fuel economy may not be
as
good and your engine may not run as smoothly.
This could lead
to costly repairs that may not be
covered by your warranty.
This light should come on, as a check to show you it is
working, when
the ignition is on and the engine is not
running. If the light doesn’t come on, have it repaired.
This light
will also come on during a malfunction in one
of two ways:
0
0
Light Flashing -- A misfire condition has been
detected.
A misfire increases vehicle emissions and
may damage the emission control system
on your
vehicle.
GM or qualified service center diagnosis
and service may be required.
Light On Steady -- An emission control system
malfunction has been detected on your vehicle.
GM
or qualified service center diagnosis and service may
be required.
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Downloaded from www.Manualslib.com manuals search engine If the Light Is Flashing If the Light Is On Steady
b I
The following may prevent more serious damage to
your vehicle:
Reducing vehicle speed.
0 Avoiding hard accelerations.
Avoiding 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 flashing and remains on steady, see “If
the Light Is On Steady” following.
If the light continues to flash, when it is safe
to do so,
stop the vehicle. Find a safe place to park your vehicle.
Turn the key 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 flashing,
follow the previous steps, and drive the vehicle
to your
dealer or qualified service center for service.
You may 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. The diagnostic system can determine if the fuel
cap has been left
off or improperly installed. A loose or
missing fuel cap will allow 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 electrical system may be wet. The condition
will usually be corrected when the electrical system
dries out. A few driving trips should turn the light off.
Are
you low on fuel?
As your engine starts
to run out of fuel, your engine may
not run as efficiently as designed since small amounts of
air are sucked into the
fuel line causing a misfire. The
system can detect this. Adding fuel should correct this
condition. Make sure to install
the fuel cap properly. It
will take a few driving trips to turn the light off.
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Downloaded from www.Manualslib.com manuals search engine Have you recently changed brands of fuel?
If
so, be sure to fuel your vehicle with quality fuel (see
“Fuel” in the Index). Poor fuel quality will cause your
engine not to run as efficiently as designed. You may
notice this as stalling after start-up, stalling when you
put the vehicle into gear, misfiring, hesitation on
acceleration or stumbling on acceleration. (These
conditions may
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,
have your dealer or qualified service center check the
vehicle. Your dealer has the proper test equipment and
diagnostic tools to fix any mechanical or electrical
problems that may have developed.
Oil Pressure Gage
The oil pressure gage
pressure in psi (pounds per
square inch) when the
shows the engine oil
8o I
engine is running. Canadian
vehicles indicate pressure in kPa (kilopascals).
OIL Wh
Oil pressure may vary with engine speed, outside
temperature and oil viscosity, but readings above the low pressure zone indicate the normal operating range.
A reading in the low pressure zone may be caused by a
dangerously low oil level or other problem causing low
oil pressure. Check your oil as soon as possible.
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