1999 GMC SONOMA light

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The following does not apply to vehicles first sold in
Canada, and to some early production vehicles.
When necessary, you may turn off the Automatic
Headlamp System and the Daytime Running
Lamps (DRL) feature by following the steps below:
1. Turn the ignition to RUN.
2. Press the DOME OVERRIDE button four times
within six seconds. After the fourth press of the
button, a chime will sound informing you that the
system is off.
3. To return to the automatic mode, push the DOME
OVERRIDE button four times within six seconds
(the chime will sound), or turn the ignition to OFF
and then to RUN again.
As with any vehicle, you should turn on the regular
headlamp system when you need it.Fog Lamps (If Equipped)
Use your fog lamps for better vision in foggy or misty
conditions. Your parking lamps or low
-beam headlamps
must be on for your fog lamps to work.
The fog lamp switch is on the instrument panel under
the lamps switch. Press the switch to turn the fog lamps
on. Press the switch again to turn them off. A light will
glow in the switch when the fog lamps are on.
The fog lamps will go off whenever your high
-beam
headlamps come on. When the high
-beam headlamps
go off, the fog lamps will come on again.

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Interior Lamps
Brightness Control
Turn the thumbwheel next to the headlamp switch up to
make your instrument panel lights brighter. Turn the
thumbwheel all the way up to turn on the interior lamps.
Illuminated Entry
Your vehicle is equipped with an illuminated entry feature.
When the doors are opened, the dome lamps will come
on if the DOME OVERRIDE button is in the ªoutº
position. If your vehicle is equipped with remote keyless
entry and all the doors are closed, or the front door
handles are lifted and released, the lamps will stay on
for a short period of time and will turn off automatically.
If you use your keyless entry transmitter to unlock the
vehicle, the interior lights will come on for a short time
whether or not the DOME OVERRIDE button is in
the ªoutº position.
Exit Lighting
With exit lighting, the interior lamps will come on when
you remove the key from the ignition to help you seewhile exiting the vehicle. These lights will stay on for a
short period of time and then will go out, if the DOME
OVERRIDE button is in the ªoutº position.
Front Map Lamps (If Equipped)
If your vehicle has front map lamps, they are located
on the inside rearview mirror. They will automatically
come on for approximately 40 seconds when the
doors are unlocked with the keyless entry transmitter
(if equipped) or until the ignition key is turned to
RUN or ACCESSORY. The lamps will also stay on
for approximately 40 seconds after you exit the
vehicle, unless you lock the doors with the keyless
entry transmitter.
You can also turn the lamps on and off by pressing the
switch near each lamp.
Dome Lamps
The dome lamps will come on when you open the doors.
You can also turn the dome lamps on by turning the
thumbwheel, located next to the parking/headlamps
knob, all the way up to the top detent position.
In this position, the dome lamps will remain on
whether the doors are opened or closed.

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If your vehicle has the center armrest compartment, lift
the cover to expose the storage area which includes slots
for cassettes or compact discs and a coinholder.
Some vehicles may have a storage pocket on the back of
the bucket or 60/40 bench seats.
Ashtray and Cigarette Lighter
Rotate the front ashtray door down to open it.
NOTICE:
Don't put papers and other things that burn
into your ashtray. If you do, cigarettes or other
smoking materials could set them on fire,
causing damage.
To remove the front ashtray, pull the bin upward.
To use the lighter, press it in all the way, and let go.
When it's ready, it will pop back by itself.

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NOTICE:
Don't hold a cigarette lighter in with your hand
while it is heating. If you do, it won't be able to
back away from the heating element when it's
ready. That can make it overload, damaging the
lighter and the heating element.
Sun Visors
To block out glare, you can swing down the sun visor.
You can also swing the visor from side to side.
Visor Vanity Mirror
Pull the sun visor down and lift the cover to expose the
vanity mirror.
Illuminated Visor Vanity Mirror
(If Equipped)
Pull the sun visor down and lift the mirror cover to turn
on the lamps.
Accessory Power Outlets
(If Equipped)
If you have accessory power outlets, you can plug in
auxiliary electrical equipment. The accessory power
outlets are located near the center of the vehicle on the
lower part of the instrument panel. Just remove the
plug from the outlet and follow the proper installation
instructions that are included with any electrical
equipment you install.
These circuits are protected by a fuse and have
maximum current levels.
NOTICE:
When using the accessory power outlets,
maximum electrical load must not exceed
20 amps. Always turn off any electrical
equipment when not in use. Leaving electrical
equipment on for extended periods will drain
your battery.

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NOTICE:
Do not operate the engine with the tachometer in
the red range, or engine damage will occur.
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 RUN 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 tone
nor the light will come on.

2-55 Air Bag Readiness Light
There is an air bag readiness light on the instrument
panel, which shows the air bag symbol. The system
checks the air bag's electrical system for malfunctions.
The light tells you if there is an electrical problem. The
system check includes the air bag sensors, the air bag
modules, the wiring, the passenger air bag suppression
circuit and the crash sensing and diagnostic module. For
more information on the air bag system, see ªAir Bagº
in the Index.
This light will come on
when you start your vehicle,
and it will flash for a few
seconds. Then the light
should go out. This means
the system is ready.
If the air bag readiness light stays on after you start the
vehicle or comes on when you are driving, your air bag
system may not work properly. Have your vehicle
serviced right away.
CAUTION:
If the air bag readiness light stays on after you
start your vehicle, it means the air bag system
may not be working properly. The air bags in
your vehicle may not inflate in a crash, or they
could even inflate without a crash. To help avoid
injury to yourself or others, have your vehicle
serviced right away if the air bag readiness light
stays on after you start your vehicle.
The air bag readiness light should flash for a few
seconds when you turn the ignition key to RUN. If the
light doesn't come on then, have it fixed so it will be
ready to warn you if there is a problem.

2-56 AIR BAG OFF Light
When you turn the right front passenger's air bag off,
this light will come on and stay on to remind you that
the air bag has been turned off. This light will go off
when you turn the air bag back on again. See ªAIR BAG
OFF Switchº in the Index for more on this, including
important safety information.CAUTION:
If the right front passenger's air bag is turned off
for a person who isn't in a risk group identified
by the national government, that person won't
have the extra protection of an air bag. In a
crash, the air bag wouldn't be able to inflate and
help protect the person sitting there.
Don't turn off the passenger's air bag unless the
person sitting there is in a risk group identified
by the national government. See ªAIR BAG OFF
Switchº in the Index for more on this, including
important safety information.

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CAUTION:
If the air bag readiness light ever comes on when
you have turned off the air bag, it means that
something may be wrong with the air bag system.
The right front passenger's air bag could inflate
even though the switch is off. If this ever
happens, don't let anyone whom the national
government has identified as a member of a
passenger air bag risk group sit in the right front
passenger's position (for example, don't secure a
rear
-facing child restraint in your vehicle) until
you have your vehicle serviced.
Charging System Indicator Light
The charging system light
will come on briefly when
you turn on the ignition, but
the engine is not running, as
a check to show you it
is working.
It should go out once the engine is running. If it stays
on, or comes on while you are driving, you may have a
problem with the charging system. It could indicate that
you have problems with a 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.