2001 Oldsmobile Alero check engine light

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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.
Safety Belt Reminder Light
When the key is turned to ON or START, a chime will
come on for about eight 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 about 20 seconds,
then it will flash for
about 55 seconds.
If the driver's belt is already buckled, neither the chime
nor the light will come on.

2-60 Charging System Indicator Light
The charging system
indicator light will come
on when you turn on the
ignition, but the engine is
not running, as a check to
show you it is working.
When the engine is running, the light should go out.
If it stays on, or comes on while you are driving and
you hear a chime, you may have a problem with the
electrical charging system. It could indicate that you
have a loose generator drive belt or another electrical
problem. Have it checked right away. Driving while this
light is on could drain your battery.
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.
Up-Shift Light (Manual Transaxle)
(If Equipped)
This light comes on when
you need to shift to the next
higher gear. See ªManual
Transaxle Operationº in
the Index.
Brake System Warning Light
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 is a brake problem.
Have your brake system inspected right away.

2-64 Engine Coolant Temperature Gage
This gage shows the engine
coolant temperature. If the
gage pointer moves into the
red area, the light comes on
and you hear a chime, your
engine is too hot. It means
that your engine coolant
has overheated.
See ªEngine Overheatingº in the Index.
Low Coolant Warning Light
This light comes on
briefly when you turn your
ignition on.
If this light comes on and stays on and you hear a chime,
the vehicle should promptly be pulled off the road and
the coolant level checked.
See ªEngine Coolantº in the Index. If there are visible
signs of steam, see ªEngine Overheatingº in the Index
before opening the hood. Have your vehicle serviced as
soon as you can.

2-66 Malfunction Indicator Lamp
(Service Engine Soon Light in the United
States or Check Engine Light in Canada)
United States Canada
Your vehicle is equipped with a computer which
monitors operation of the fuel, ignition and emission
control systems.
This system is called OBD II (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 or CHECK ENGINE 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.
NOTICE:
Modifications made to the engine, transaxle,
exhaust, intake or fuel system of your vehicle or
the replacement of the original tires with other
than those of the same Tire Performance
Criteria (TPC) can affect your vehicle's emission
controls and may cause the SERVICE ENGINE
SOON or the CHECK ENGINE light to come on.
Modifications to these systems could lead to
costly repairs not covered by your warranty.
This may also result in a failure to pass a
required Emission Inspection/Maintenance test.

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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:

Light Flashing
-- A misfire condition has been
detected. A misfire increases vehicle emissions and
may damage the emission control system on your
vehicle. Dealer or qualified service center diagnosis
and service may be required.

Light On Steady
-- An emission control system
malfunction has been detected on your vehicle.
Dealer or qualified service center diagnosis and
service may be required.
If the Light Is Flashing
The following may prevent more serious damage to
your vehicle:

Reducing vehicle speed.

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
ªIf the Light Is On Steadyº 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 ªIf the Light
Is On Steadyº following. If the light is still flashing,
follow the previous steps, and drive the vehicle to your
dealer or qualified service center for service.
If the Light Is On Steady
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. See ªFilling Your Tankº in the Index. 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.

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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.
Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel. See
ªFuelº 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.Emissions Inspection and Maintenance Programs
Some state/provincial and local governments have or
may begin programs to inspect the emission control
equipment on your vehicle. Failure to pass this
inspection could prevent you from getting a
vehicle registration.
Here are some things you need to know in order to help
your vehicle pass an inspection:
Your vehicle will not pass this inspection if the
SERVICE ENGINE SOON or CHECK ENGINE light is
on or not working properly.
Your vehicle will not pass this inspection if the
OBD (on
-board diagnostic) system determines that
critical emission control systems have not been
completely diagnosed by the system. The vehicle would
be considered not ready for inspection. This can happen
if you have recently replaced your battery or if your
battery has run down. The diagnostic system is designed
to evaluate critical emission control systems during
normal driving. This may take several days of routine
driving. If you have done this and your vehicle still does
not pass the inspection for lack of OBD system
readiness, see your dealer or qualified service center to
prepare the vehicle for inspection.

2-69 Oil Pressure Light
If you have a low engine oil
pressure problem, this light
will stay on after you start
your engine, or come on
and you will hear a chime
when you are driving.
This indicates that your engine is not receiving enough
oil. The engine could be low on oil, or could have some
other oil problem. Have it fixed immediately.
When the ignition is on but the engine is not running, the
light will come on as a test to show you it is working, but
the light will go out when the engine is running. If it
doesn't come on with the ignition on, you may have a
problem with the bulb. Have it fixed right away.CAUTION:
Don't keep driving if the oil pressure is low.
If you do, your engine can become so hot that it
catches fire. You or others could be burned.
Check your oil as soon as possible and have your
vehicle serviced.
NOTICE:
Damage to your engine from neglected oil
problems can be costly and is not covered by
your warranty.

2-70 Low Oil Light (If Equipped)
If your vehicle is equipped
with a 3400 V6 engine, then
you will have a LOW OIL
light in your instrument
panel cluster.
This light will come on briefly when you start your vehicle.
If the light stays on after starting your vehicle, or comes
on and chimes while you are driving, your engine oil
level should be checked.
Prior to checking the oil level, be sure your vehicle has
been shut off for several minutes and is on a level
surface. Check the oil level on your dipstick and bring it
to the proper level. See ªEngine Oilº in the Index.
A false LOW OIL light may be generated when parking
on steep grades.
The oil level monitoring system only checks oil level
during the brief period between when the key is on and
the engine is cranking. It does not monitor engine oil
level when the engine is running. Additionally, an oil
level check is only performed if the engine has been
turned off for a considerable period of time allowing the
oil normally in circulation to drain back into the oil pan.
Change Oil Light
The CHANGE OIL light
should come on briefly as a
bulb check when you start
the engine. If the light
doesn't come on, have
it serviced.
If the CHANGE OIL light comes on and stays on after
you start the engine, have the oil changed.
To reset the CHANGE OIL light, see ªEngine Oil,
When to Changeº in the Index.