2008 GMC SAVANA light

Malfunction Indicator Lamp
Check Engine Light
A computer system called OBD II (On-Board
Diagnostics-Second Generation) monitors operation
of the fuel, ignition, and emission control systems.
It makes sure 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 an OBD II problem
and service is required.
Malfunctions often are indicated by the system before
any problem is apparent. This can 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, the emission controls might
not work as well, your vehicle’s fuel economy might
not be as good, and the engine might not run as
smoothly. This could lead to costly repairs that might
not be covered by your warranty.Notice:Modications made to the engine,
transmission, 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 can cause this light to come on.
Modications to these systems could lead to costly
repairs not covered by your warranty. This could
also result in a failure to pass a required Emission
Inspection/Maintenance test. SeeAccessories
and Modifications on page 5-3.
This light comes on, as a check to show it is working,
when the ignition is turned ON/RUN but the engine is not
running. If the light does not come on, have it repaired.
This light also comes on during a malfunction in
one of two ways:
•Light Flashing— A misfire condition has been
detected. A misfire increases vehicle emissions
and could damage the emission control system
on your vehicle. Diagnosis and service might
be required.
•Light On Steady— An emission control system
malfunction has been detected on your vehicle.
Diagnosis and service might be required.
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If the Light is Flashing
The following can prevent more serious damage to your
vehicle:
•Reduce vehicle speed.
•Avoid hard accelerations.
•Avoid 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 the vehicle.
Turn the ignition 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 see your dealer/retailer
for service as soon as possible.
If the Light Is On Steady
You might 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 the Tank on page 5-10.
The diagnostic system can determine if the fuel cap hasbeen left off or improperly installed. A loose or missing
fuel cap allows 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 vehicle’s electrical system might be wet.
The condition is usually 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
Gasoline Octane on page 5-6. Poor fuel quality causes
the engine not to run as efficiently as designed. You
might 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 might 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/retailer can check the vehicle. Your dealer/
retailer has the proper test equipment and diagnostic
tools to fix any mechanical or electrical problems that
might have developed.
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Emissions Inspection and Maintenance
Programs
Some state/provincial and local governments have or
might 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 to help your
vehicle pass an inspection:
Your vehicle will not pass this inspection if the 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 the battery or if the battery
has run down. The diagnostic system is designed to
evaluate critical emission control systems during normal
driving. This can 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
dealer/retailer can prepare the vehicle for inspection.
Oil Pressure Gage
The oil pressure gage shows the engine oil pressure
in psi (pounds per square inch) when the engine
is running. Canadian vehicles indicate pressure in
kPa (kilopascals).
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.United States
Canada
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{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.
Oil Pressure Light
{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.
This light will come on
briefly when you start
your engine. If it does
not, have your vehicle
serviced.
When the light comes on and stays on, it means that oil
is not flowing through your engine properly. You could be
low on oil and you might have some other system
problem.
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Security Light
For information regarding
this light and the vehicle’s
security system, see
PASS-Key
®III+ Operation
on page 2-17.
Cruise Control Light
This light comes on
whenever you set the
cruise control.
The light goes out when the cruise control is turned off.
SeeCruise Control on page 3-10for more information.
Highbeam On Light
This light comes on when
the high-beam headlamps
are in use.
SeeHeadlamp High/Low-Beam Changer on page 3-9
for more information.
Tow/Haul Mode Light
This light comes on when
the Tow/Haul mode has
been activated.
For more information, seeTow/Haul Mode on page 2-25.
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To adjust for compass variance, use the following
procedure:
Compass Variance (Zone) Procedure
1. Do not set the compass zone when the vehicle is
moving. Only set it when the vehicle is in PARK (P).
Press the vehicle information button until PRESS
VTO CHANGE COMPASS ZONE displays.
2. Find the vehicle’s current location and variance
zone number on the map.
Zones 1 through 15 are available.3. Press the set/reset button to scroll through and
select the appropriate variance zone.
4. Press the trip/fuel button until the vehicle heading,
for example, N for North, is displayed in the DIC.
5. If calibration is necessary, calibrate the compass.
See “Compass Calibration Procedure” following.Compass Calibration
The compass can be manually calibrated. Only calibrate
the compass in a magnetically clean and safe location,
such as an open parking lot, where driving the vehicle
in circles is not a danger. It is suggested to calibrate
away from tall buildings, utility wires, manhole covers,
or other industrial structures, if possible.
If CAL should ever appear in the DIC display, the
compass should be calibrated.
If the DIC display does not show a heading, for example,
N for North, or the heading does not change after
making turns, there may be a strong magnetic field
interfering with the compass. Such interference may
be caused by a magnetic CB or cell phone antenna
mount, a magnetic emergency light, magnetic note
pad holder, or any other magnetic item. Turn off
the vehicle, move the magnetic item, then turn on
the vehicle and calibrate the compass.
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To calibrate the compass, use the following procedure:
Compass Calibration Procedure
1. Before calibrating the compass, make sure the
compass zone is set to the variance zone in
which the vehicle is located. See “Compass
Variance (Zone) Procedure” earlier in this section.
Do not operate any switches such as window,
sunroof, climate controls, seats, etc. during
the calibration procedure.
2. Press the vehicle information button until
PRESS
VTO CALIBRATE COMPASS displays.
3. Press the set/reset button to start the compass
calibration.
4. The DIC will display CALIBRATING: DRIVE IN
CIRCLES. Drive the vehicle in tight circles at less
than 5 mph (8 km/h) to complete the calibration.
The DIC will display CALIBRATION COMPLETE
for a few seconds when the calibration is complete.
The DIC display will then return to PRESS
VTO
CALIBRATE COMPASS.
DIC Warnings and Messages
Messages are displayed on the DIC to notify the driver
that the status of the vehicle has changed and that some
action may be needed by the driver to correct the
condition. Multiple messages may appear one after
another.
Some messages may not require immediate action, but
you can press any of the DIC buttons on the instrument
panel to acknowledge that you received the messages
and to clear them from the display.
Some messages cannot be cleared from the DIC
display because they are more urgent. These messages
require action before they can be cleared. You should
take any messages that appear on the display seriously
and remember that clearing the messages will only
make the messages disappear, not correct the problem.
The following are the possible messages that can be
displayed and some information about them.
If your vehicle has the DURAMAX
®Diesel engine, see
the DURAMAX®Diesel manual for more information.
AUTOMATIC LIGHT CONTROL OFF
This message displays when the automatic headlamps
are turned off. SeeExterior Lamps on page 3-13for
more information.
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AUTOMATIC LIGHT CONTROL ON
This message displays when the automatic headlamps
are turned on. SeeExterior Lamps on page 3-13for
more information.
CALIBRATING: DRIVE IN CIRCLES
This message displays when calibrating the compass.
Drive the vehicle in circles at less than 5 mph (8 km/h)
to complete the calibration. SeeDIC Compass on
page 3-47for more information.
CALIBRATION COMPLETE
This message displays when the compass calibration is
complete. SeeDIC Compass on page 3-47for more
information.
CARGO DOOR OPEN
This message displays and a chime sounds if the cargo
door is open while the ignition is in ON/RUN. Turn off
the vehicle and check the cargo door. Restart the
vehicle and check for the message on the DIC display.
CHANGE ENGINE OIL SOON
This message displays when the engine oil needs to
be changed. When you change the engine oil, be sure
to reset the CHANGE ENGINE OIL SOON message.
SeeEngine Oil Life System on page 5-18for information
on how to reset the message. SeeEngine Oil (Gasoline
Engine) on page 5-15andScheduled Maintenance
on page 6-4for more information.
CHECK TIRE PRESSURE
If your vehicle has the Tire Pressure Monitor
System (TPMS), this message displays when the
pressure in one or more of the vehicle’s tires needs to
be checked. This message also displays LEFT FRONT,
RIGHT FRONT, LEFT REAR, or RIGHT REAR to
indicate which tire needs to be checked. You can receive
more than one tire pressure message at a time. To read
the other messages that may have been sent at the
same time, press the set/reset button. If a tire pressure
message appears on the DIC, stop as soon as you can.
Have the tire pressures checked and set to those shown
on the Tire Loading Information label. SeeTires on
page 5-53,Loading Your Vehicle on page 4-20, and
Inflation - Tire Pressure on page 5-60. The DIC also
shows the tire pressure values. SeeDIC Operation
and Displays on page 3-42. If the tire pressure is low,
the low tire pressure warning light comes on. SeeTire
Pressure Light on page 3-35.
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