2007 GMC SAVANA engine

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.
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SeePassenger Sensing System on page 89for
more on this, including important safety information.
If, after several seconds, all status indicator lights
remain on, or if there are no lights at all, there
may be a problem with the lights or the passenger
sensing system. See your dealer for service.
{CAUTION:
If the off indicator and the airbag
readiness light ever come on together, it
means that something may be wrong with
the airbag system. If this ever happens,
have the vehicle serviced promptly,
because an adult-size person sitting in the
right front passenger seat may not have
the protection of the frontal airbag. See
Airbag Readiness Light on page 169.
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 generator 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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Voltmeter Gage
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.
Brake System Warning Light
With the ignition on, the brake system warning
light will come on when you set your parking
brake. The light will stay on if your parking brake
doesn’t release fully. If it stays on after your
parking brake is fully released, 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.
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This light should come on briefly when you turn
the ignition key to RUN. If it doesn’t come on then,
have it fixed so it will be ready to warn you if
there’s a problem.
If the light comes on while you are driving, pull off
the road and stop carefully. You may notice that the
pedal is 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 on page 264.
{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
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.
United StatesCanada
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Engine Coolant Temperature Gage
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.
SeeEngine Overheating on page 309.
Malfunction Indicator Lamp
Check Engine Light
Your vehicle has 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.
United StatesCanada
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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,
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 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. SeeAccessories
and Modifications on page 286.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 misfire condition has
been detected. A misfire 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.
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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 “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 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 the Tank on page 292.
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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Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel.
SeeGasoline Octane on page 288. 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, your dealer can 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 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 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 dealer can prepare the vehicle for
inspection.
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