2005 PONTIAC BONNEVILLE engine

Engine Coolant Temperature Gage
(V6 Engine)
This gage shows the engine coolant temperature.To prevent engine overheating, the air conditioning
compressor will turn off automatically just prior to the
gage pointer entering the shaded area. As the
engine cools down, the air conditioning compressor will
automatically turn back on. On vehicles equipped
with the Driver Information Center (DIC), the message
ENGINE HOT... A/C DISABLED will appear on the
DIC display and a warning chime will sound.
If the gage pointer moves into the shaded area, your
engine is too hot. On vehicles equipped with the
systems monitor, the CHECK GAGES light will come on
and a warning chime will sound. On vehicles with a
DIC, a CHECK GAGES TEMPERATURE message will
be displayed and a warning chime will sound. See
DIC Warnings and Messages on page 3-62for more
information.
SeeEngine Overheating (3.8L V6 Engine) on page 5-36
orEngine Overheating (4.6L V8 Engine) on page 5-38,
for information on what to do if your engine overheats. United States
Canada
3-45

Engine Coolant Temperature Gage
(V8 Engine)
This gage shows the engine coolant temperature.
To prevent engine overheating, the air conditioning
compressor will turn off automatically just prior to
the gage pointer entering the shaded area. As the
engine cools down, the air conditioning compressor will
automatically turn back on. On vehicles equipped
with the Driver Information Center (DIC), the message
ENGINE HOT... A/C DISABLED will appear on the
DIC display and a warning chime will sound.If the gage pointer moves into the shaded area, your
engine is too hot. On vehicles equipped with the
systems monitor, the CHECK GAGES light will come on
and a warning chime will sound. On vehicles with a
DIC, a CHECK GAGES TEMPERATURE message will
be displayed and a warning chime will sound. See
DIC Warnings and Messages on page 3-62for more
information.
On vehicles with a V8 engine, if the coolant temperature
is above normal operating range, the message
ENGINE HOT...IDLE ENGINE will appear. This means
that you should reduce the engine load and speed
to prevent the engine from overheating.
If an engine overheat condition exists, the message
ENGINE HOT...STOP ENGINE will appear. This means
that you should pull off the road, stop your vehicle,
and turn off the engine as soon as possible.
SeeEngine Overheating (3.8L V6 Engine) on page 5-36
orEngine Overheating (4.6L V8 Engine) on page 5-38,
for information on what to do if your engine overheats.
Your vehicle is equipped with an Overheated Engine
Protection Operating Mode, which alternates ring
groups of cylinders to help prevent engine damage. See
“Overheated Engine Protection Operating Mode”
underEngine Overheating (3.8L V6 Engine) on
page 5-36orEngine Overheating (4.6L V8 Engine) on
page 5-38for more information. United States
Canada
3-46

If your coolant level is low, the message LOW ENGINE
COOLANT will appear on the DIC. This means that
you should check your coolant level as soon as possible.
SeeEngine Coolant (3.8L V6 Engine) on page 5-31
orEngine Coolant (4.6L V8 Engine) on page 5-34
for more information.
Tire Pressure Light
The check tire pressure system can alert you to a large
change in the pressure of one tire.
After the system has been
properly calibrated, the
TIRE PRESS light
will come on if a pressure
difference (low pressure)
is detected in one tire.
The light will stay on until you turn off the ignition or
reset (calibrate) the system. SeeCheck Tire Pressure
System on page 5-83.The TIRE PRESS light also comes on briey when you
turn your ignition key to START. If the light doesn’t
come on then, have it xed so it will be there to tell you
if the pressure in a tire is low.
If the anti-lock brake system warning light comes on,
the check tire pressure system may not be working
properly. See your dealer for service. Also, see
Anti-Lock Brake System Warning Light on page 3-42.
On vehicles with the optional Driver Information
Center (DIC), a CHECK TIRE PRESSURE message will
appear when the system detects a pressure difference
(low pressure) in one tire. SeeDIC Warnings and
Messages on page 3-62for more information.
3-47

Malfunction Indicator Lamp
Service Engine Soon Light in the
United States or With V6 Engine in
Canada or Check Engine Light With
V8 Engine in 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 Enginelight 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. United States and V6 in
Canada
Canada (V8 Only)
3-48

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 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 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 5-8. 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.
3-49

Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel. See
Gasoline Octane on page 5-5. 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, misring, 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,
your dealer can check the vehicle. Your dealer has
the proper test equipment and diagnostic tools to x 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, your GM dealer can prepare the
vehicle for inspection.
3-50

Oil Pressure Gage (V6 Engine)
Readings above the shaded warning zone indicate the
normal operating range. Oil pressure may vary with
engine speed, outside temperature and oil viscosity.
A reading in the shaded warning zone may be caused
by a low oil level or another problem causing low oil
pressure. On vehicles with the systems monitor,
the CHECK GAGES light will come on and a warning
chime will sound.On vehicles with a DIC, a CHECK GAGES OIL
PRESSURE message will be displayed and a warning
chime will sound. SeeDIC Warnings and Messages
on page 3-62for more information.
{CAUTION:
Do not keep driving if the oil pressure is low. If
you do, your engine can become so hot that it
catches re. You or others could be burned.
Check your oil as soon as possible and have
your vehicle serviced.
Notice:Lack of proper engine oil maintenance may
damage the engine. The repairs would not be
covered by your warranty. Always follow the
maintenance schedule in this manual for changing
engine oil. United States
Canada
3-51

Oil Pressure Gage (V8 Engine)
Readings above the shaded warning zone indicate the
normal operating range. Oil pressure may vary with
engine speed, outside temperature and oil viscosity.
A reading in the shaded warning zone may be caused
by a low oil level or another problem causing low oil
pressure. On vehicles with the systems monitor,
the CHECK GAGES light will come on and a warning
chime will sound.On vehicles with a DIC, a CHECK GAGES OIL
PRESSURE message will be displayed and a warning
chime will sound. SeeDIC Warnings and Messages
on page 3-62for more information.
{CAUTION:
Do not keep driving if the oil pressure is low. If
you do, your engine can become so hot that it
catches re. You or others could be burned.
Check your oil as soon as possible and have
your vehicle serviced.
Notice:Lack of proper engine oil maintenance may
damage the engine. The repairs would not be
covered by your warranty. Always follow the
maintenance schedule in this manual for changing
engine oil. United States
Canada
3-52