2005 PONTIAC GRAND PRIX engine

Warning Lights, Gages, and
Indicators
This part describes the warning lights and gages that
may be on the vehicle. The pictures help to 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
the 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 the vehicle’s functions. As
the details show on the next few pages, some warning
lights come on briey when the engine is started
just to indicate they are 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 the vehicle’s functions. Often gages and
warning lights work together to indicate when there is a
problem with the vehicle.
When one of the warning lights comes on and stays on
while the vehicle is being driven, or when one of the
gages shows there may be a problem, check the section
that tells you what to do about it. Follow this manual’s
advice. Waiting to do repairs can be costly – and
even dangerous. So please get to know the vehicle’s
warning lights and gages. They can be a big help.
The vehicle also has a Driver Information Center (DIC)
that works along with the warning lights and gages.
SeeDriver Information Center (DIC) on page 3-49for
more information.
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Speedometer and Odometer
The speedometer shows the vehicle’s speed in both
miles per hour (mph) and kilometers per hour (km/h).
The odometer, located on the Driver Information Center
(DIC) display, shows how far the vehicle has been
driven, in either miles or kilometers. SeeDIC Controls
and Displays (Base Level DIC) on page 3-49orDIC
Controls and Displays (Uplevel DIC with Trip Computer)
on page 3-57for more information.
If the vehicle has the Head-Up Display (HUD) the speed
will also be displayed on the HUD screen.
If a vehicle has to have a new odometer installed, a
new one can be set to the mileage total of the old
odometer, if that can be done. If it cannot, than it will be
set at zero and a label must be put on the driver’s
door to show the old mileage reading when the new
odometer was installed.
Trip Odometer
The trip odometer, located in the Driver Information
Center (DIC), tells how far the vehicle has driven since it
was last reset. The miles (kilometers) for two different
trips can be viewed. SeeDIC Controls and Displays
(Base Level DIC) on page 3-49orDIC Controls and
Displays (Uplevel DIC with Trip Computer) on page 3-57
for more information on setting the trip odometer.
Tachometer
The tachometer displays the engine speed in revolutions
per minute (rpm).
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{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 ash for a
few seconds when the ignition key is turned to RUN.
If the light does not come on then, have it xed so it
will be ready to warn you if there is a problem.
Up-Shift Light
This symbol can appear
on the instrument panel
if the vehicle has a
supercharged engine
and the shift lever is
in the MANUAL (M)
transaxle position.
It will appear as a prompt to up-shift to the next gear
using one of the Tap-Shift™ paddles located on
the steering wheel.
If equipped, this symbol will appear on the Head Up
Display (HUD) only.
SeeAutomatic Transaxle Operation on page 2-25and
Head-Up Display (HUD) on page 3-20for more
information.
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{CAUTION:
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
have pulled off the road and stopped carefully,
have the vehicle towed for service.
Anti-Lock Brake System
Warning Light
If the vehicle has the
Anti-lock Brake System
(ABS), this light will come
on when the engine is
started and may stay on
for several seconds.
That is normal.If the ABS warning light comes on and stays on, there
may be a problem with the anti-lock portion of the brake
system. If the brake system warning light is not on,
the vehicle still has brakes, but it does not have anti-lock
brakes. SeeBrake System Warning Light on page 3-40.
If the light stays on, the vehicle needs service. If the
light comes on while the vehicle is being driven, stop as
soon as possible and turn the ignition off. Then start
the vehicle again to reset the system. If the light
still stays on, or comes on again while driving, the
vehicle needs service. If the regular brake system
warning light is not on, the vehicle still has brakes, but it
does not have anti-lock brakes. If the brake system
warning light is also on, the vehicle does not have
anti-lock brakes and there is a problem with the regular
brakes. SeeBrake System Warning Light on page 3-40.
If both the brake system warning light and the anti-lock
brake system light is on, pull off the road and have
the vehicle towed for service.
The anti-lock brake system warning light will come on
briey when the ignition key is turned to RUN. This
is normal. If the light does not come on then, have it
xed so it will be ready to warn you if there is a problem.
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Traction Control System (TCS)
Warning Light
If the vehicle has a 3800 supercharged V6 engine and
the Traction Control System (TCS), one of these
lights may come on for the following reasons:
The Traction Control button, located on the center
console, is pressed, turning the system off. The
light will stay on. To turn the system back on, press
the button again and the warning light should go
out. SeeTraction Control System (TCS) on
page 4-9for more information.
If there is a brake system problem that is specically
related to traction control, the TCS will turn off and
the warning light will come on.
If the brakes begin to overheat, the TCS will turn off
and the warning light will come on until the brakes
cool down.If the traction control system warning light comes on
and stays on for an extended period of time when the
system is turned on, the vehicle needs service.
Enhanced Traction System
Warning Light
If the vehicle has the 3800 V6 engine and the Enhanced
Traction System (ETS), one of these lights may come
on for the following reasons.
If the Traction Control button located on the center
console is pressed, turning the system off. This
light will come on and stay on. To turn the system
back on, press the button again and the warning
light should turn off. SeeEnhanced Traction
System (ETS) on page 4-10.
If the system is affected by an engine-related
problem, the system will turn off and the warning
light will come on.
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If the light comes on and stays on for an extended
period of time when the system is turned on, the vehicle
needs service.
Engine Coolant Temperature
Warning Light
This light indicates that
the engine coolant
has overheated or the
radiator cooling fan is
not working.
If the vehicle has been operating under normal driving
conditions, pull off the road, stop the vehicle, and turn off
the engine as soon as possible.
SeeCooling System on page 5-30for more information.
Engine Coolant Temperature Gage
The vehicle has a gage
that shows the engine
coolant temperature.
If the gage pointer moves into the shaded area, the
engine is too hot. That reading means the engine
coolant has overheated. If you have been operating the
vehicle under normal driving conditions, you should
pull off the road, stop the vehicle, and turn off the engine
as soon as possible.
SeeCooling System on page 5-30for more information.
3-43

Malfunction Indicator Lamp
Check Engine Light
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 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 awhile, 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:Modications 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 this light to come on.
Modications 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 does not come on, have it
repaired. This light will also come on during a
malfunction in one of two ways:
Light Flashing— A misre condition has been
detected. A misre increases vehicle emissions and
may damage the emission control system on your
vehicle. Diagnosis and service may be required.
Light On Steady— An emission control system
malfunction has been detected on your vehicle.
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 possibleIf 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 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
ashing, follow the previous steps, and see your dealer
for service as soon as possible.
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. SeeFilling Your Tank on page 5-7. 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.
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