ignition CHEVROLET TAHOE 2007 3.G Service Manual

Fog Lamps
-(Fog Lamps):If your vehicle has fog lamps,
the button is located on the instrument panel
to the left of the steering column and below the
dome lamp override button.
The ignition must be in RUN and the parking
lamps must be on for the fog lamps to work.
To turn the fog lamps on, press the fog lamps
button. A light comes on in the instrument
panel cluster to let you know that the fog lamps
are on. Press the button again to turn the fog
lamps off.
When the fog lamps are turned on, the low-beam
headlamps automatically turn on.
The fog lamps turn off while you change to
high-beam headlamps. When the high-beam
headlamps go off, the fog lamps will come
on again.
Fog lamps should only be used in foggy conditions
since they could be distracting to oncoming
drivers in clear weather conditions.
Some localities have laws that require the
headlamps to be on along with the fog lamps.
Auxiliary Roof Mounted Lamp
If your vehicle has this feature, this button includes
wiring provisions for a dealer or a qualied
service center to install an auxiliary roof lamp.
This button is located
on the overhead
console.
When the wiring is connected to an auxiliary roof
mounted lamp, pressing the bottom of the
button will activate the lamp and illuminate an
indicator light at the bottom of this button. Pressing
the top of the button will turn off the roof mounted
lamp and indicator.
The emergency roof lamp circuit is fused at
30 amps, so the total current draw of the attached
lamps should be less than this value. The
attachment points for the roof lamp circuits are
two blunt cut wires located above the overhead
console, a dark green switched power wire and a
black ground wire.
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Entry Lighting
Your vehicle has an illuminated entry feature.
When the doors are opened, the dome lamps will
come on if the dome override button is in the
extended position. If the dome override button is
pressed in, the lamps will not come on.
Exit Lighting
With exit lighting, the interior lamps will come on
when the key is removed from the ignition. They
will turn off automatically in 20 seconds. The lights
will not come on if the dome override button is
pressed in.
Reading Lamps
If your vehicle has reading lamps they are located
on the overhead console.
To turn on the reading lamps, press the button
located next to each lamp. To turn them off, press
the button again.Your vehicle may also have reading lamps in other
locations. To turn the lamps on or off, press the
button located next to the lamp.
The lamps are xed and cannot be adjusted.
Electric Power Management
The vehicle has Electric Power Management (EPM)
that estimates the battery’s temperature and state
of charge. It then adjusts the voltage for best
performance and extended life of the battery.
When the battery’s state of charge is low, the
voltage is raised slightly to quickly put the charge
back in. When the state of charge is high, the
voltage is lowered slightly to prevent overcharging.
If the vehicle has a voltmeter gage or voltage
display on the Driver Information Center (DIC), you
may see the voltage move up or down. This is
normal. If there is a problem, an alert will be
displayed.
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The battery can be discharged at idle if the
electrical loads are very high. This is true for
all vehicles. This is because the generator
(alternator) may not be spinning fast enough at
idle to produce all the power that is needed for very
high electrical loads.
A high electrical load occurs when several of the
following loads are on: headlamps, high beams,
fog lamps, rear window defogger, climate
control fan at high speed, heated seats, engine
cooling fans, trailer loads, and loads plugged into
accessory power outlets.
EPM works to prevent excessive discharge of the
battery. It does this by balancing the generator’s
output and the vehicle’s electrical needs. It
can increase engine idle speed to generate more
power, whenever needed. It can temporarily
reduce the power demands of some accessories.Normally, these actions occur in steps or levels,
without being noticeable. In rare cases at the
highest levels of corrective action, this action may
be noticeable to the driver. If so, a Driver
Information Center (DIC) message might be
displayed, such as Battery Saver Active or Service
Battery Charging System. If this message is
displayed, it is recommended that the driver
reduce the electrical loads as much as possible.
SeeDIC Warnings and Messages on page 270.
Battery Run-Down Protection
This feature shuts off the dome, and reading
lamps if they are left on for more than 10 minutes
when the ignition is off. This will keep the
battery from running down.
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To use the power outlet, lift the spring cap and
insert electrical 12V device plug. To close
the power outlet, remove 12V electrical device
plug and the spring cap will close.
The accessory power outlets are powered, even
with the ignition off. Continuing to use power
outlets while the ignition is off may cause
the vehicle’s battery to run down.
Notice:If electrical devices are left plugged
into a power outlet, the battery may drain
causing your vehicle not to start or damage to
the battery. This would not be covered by
the warranty. Always unplug all electrical
devices when turning off your vehicle.
Certain power accessory plugs may not be
compatible to the accessory power outlet and
could result in blown adapter or vehicle fuses.
If you experience a problem, see your dealer for
additional information on the accessory power
plugs.Notice:Adding any electrical equipment to
your vehicle may damage it or keep other
components from working as they should. The
repairs would not be covered by your
warranty. Do not use equipment exceeding
maximum amperage rating of 20 amperes.
Check with your dealer/retailer before adding
electrical equipment.
When adding electrical equipment, be sure to
follow the proper installation instructions included
with the equipment. Do not use equipment
exceeding the maximum amperage rating of
20 amperes.
Notice:Improper use of the power outlet can
cause damage not covered by your warranty.
Do not hang any type of accessory or
accessory bracket from the plug because the
power outlets are designed for accessory
power plugs only.
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Speedometer and Odometer
Your speedometer lets you see your speed
in both miles per hour (mph) and kilometers per
hour (km/h).
Your odometer shows how far your vehicle has
been driven, in either miles (used in the United
States) or kilometers (used in Canada).
Trip Odometer
The trip odometer can tell you how far your
vehicle has been driven since you last set the trip
odometer to zero.
Press the reset button, located on the instrument
panel cluster next to the trip odometer display,
to toggle between the trip odometer and the
regular odometer. Holding the reset button for
approximately one second while the trip odometer
is displayed will reset it.
To display the odometer reading with the ignition
off, press the reset button.
Tachometer
Your tachometer displays the engine speed in
revolutions per minute (rpm).
Safety Belt Reminder Light
When the key is turned to RUN or START, a
chime will sound for several seconds to remind
people to buckle their safety belts. The driver
safety belt light will also come on and stay on for
several seconds. Then it will ash for several
more. You should buckle your seat belt.
This chime and light will
be repeated if the driver
remains unbuckled
and the vehicle
is in motion.
If the driver’s belt is buckled, neither the chime nor
the light will come on.
SeePassenger Sensing System on page 101for
more information.
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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.
If the airbag readiness light stays on after you
start the vehicle or comes on when you are driving,
your airbag system may not work properly.
Have your vehicle serviced right away.
The airbag readiness light should ash for a
few seconds when you turn the ignition key 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.
Passenger Airbag Status Indicator
Your vehicle has the passenger sensing system.
Your overhead console has a passenger airbag
status indicator.
When the ignition key is turned to RUN or START,
the passenger airbag status indicator will light
ON and OFF, or the symbol for on and off,
for several seconds as a system check. Then,
after several more seconds, the status indicator
will light either ON or OFF, or either the on
or off symbol, to let you know the status of the
right front passenger’s frontal airbag.
If the word ON or the on symbol is lit on the
passenger airbag status indicator, it means that
the right front passenger’s frontal airbag is enabled
(may inate).
United StatesCanada
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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 245.
Charging System Light
The charging system
light will come on briey
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 the
generator, the generator drive belt, or another
electrical problem. Have it checked right away.
Driving while this light is on could drain your
battery.
When this light comes on, the Driver Information
Center (DIC) will also display the SERVICE
BATTERY NOT CHARGING SYSTEM message.
SeeDIC Warnings and Messages on page 270for
more information.
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, to reduce the drain on
your battery.
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Voltmeter Gage
When your engine is not
running, but the ignition
is in RUN, 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. The charging
system regulates voltage based on the state of the
battery for improved fuel economy and battery
life. The gage may transition from a higher to lower
or a lower to higher reading, this is normal.
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 full power. If
there is a problem with the battery charging
system, this light will come on or the SERVICE
BATTERY CHARGING SYSTEM DIC message will
display. SeeDIC Warnings and Messages on
page 270andCharging System Light on page 248
for more information.
Brake System Warning Light
With the ignition on, the brake system warning
light will come on when you set the parking brake.
If you try to drive with the parking brake engaged,
a chime will sound when the vehicle speed is
greater than 5 mph (8 km/h).
Your vehicle’s hydraulic brake system is divided
into two parts. If one part is not 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 and a chime
sounds there could be a brake problem. Have
your brake system inspected right away.
249

This light may also come on due to low brake
uid. SeeBrakes on page 486for more
information.
This light should come on briey when you turn
the ignition key to RUN. If it does not come
on then, have it xed so it will be ready to warn
you if there is a problem.
{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.
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 may go closer
to the oor. It may take longer to stop. If the
light is still on, have the vehicle towed for service.
SeeTowing Your Vehicle on page 417.
United StatesCanada
250

Anti-Lock Brake System Warning
Light
With the Anti-Lock Brake
System (ABS), this
light will come on when
you start your engine
and may stay on for
several seconds.
That 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.
If the light stays on, or comes on when you are
driving, your vehicle needs service. A chime
will sound when the light stays on. If the regular
brake system warning light is not on, you still have
brakes, but you do not have ABS.If the regular brake system warning light is also on
you do not have ABS and there is a problem
with your regular brakes. In addition to both lights,
you will also hear a chime sound on the rst
occurrence of a problem and each time the vehicle
is shut off and then restarted. SeeBrake System
Warning Light on page 249.
The ABS warning light should come on briey
when you turn the ignition key 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.
251