2007 CHEVROLET SILVERADO service

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 281.
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 turned off. The cargo lamp
will shut off after 20 minutes. This will keep
the battery from running down.
Ultrasonic Rear Parking
Assist (URPA)
If your vehicle has the Ultrasonic Rear Parking
Assist (URPA) system it is designed to help you
park while in Reverse (R). It operates only at
speeds less than 5 mph (8 km/h). URPA helps
make parking easier and helps you avoid colliding
with objects such as parked vehicles. The URPA
system detects objects that are close to the rear of
the vehicle which are at least 10 inches (25.4 cm)
off the ground and below hood or trunk level. The
system detects objects up to 8 feet (2.5 m) behind
your vehicle. The URPA sensors determine how
close these objects are from your bumper within
this area.
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Airbag Readiness Light
There is an airbag readiness light on the instrument
panel cluster, which shows the airbag symbol. The
system checks the airbag’s electrical system for
malfunctions. The light tells you if there is an
electrical problem. The system check includes the
airbag sensors, the airbag modules, the wiring and
the crash sensing and diagnostic module and, if
equipped, the passenger sensing system. For more
information on the airbag system, seeAirbag
System on page 85.
This light will come on
when you start your
vehicle, and it will ash
for a few seconds.
This means the system
is ready.
If the airbag readiness light stays on after the
vehicle is started or comes on while you are
driving, the airbag system may not be working
properly. Have your vehicle serviced right away.
Airbag Off Light
If your vehicle has an airbag on-off switch, it also
has a passenger airbag status indicator located
in the overhead console.
When the ignition key is turned to RUN or START,
the passenger airbag status indicator ON and
OFF, or the symbol for on and off, will light
for several seconds as a system check. Then,
after several more seconds, the status indicator
ON or OFF, or either the on or off symbol, will light
to let you know the status of the right front
passenger’s frontal airbag.
When you manually turn the right front passenger’s
airbag off using the airbag on-off switch in the
glove box, the indicator light OFF or the off symbol
will come on and stay on to remind you that the
airbag has been turned off.
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This light will go off when you turn the airbag on.
SeeAirbag Off Switch on page 95for more on
this, including important safety information.
{CAUTION:
If the right front passenger’s airbag is
turned off for a person who is not in a risk
group identied by the national
government, that person will not have the
extra protection of an airbag. In a crash,
the airbag will not be able to inate and
help protect the person sitting there.
Do not turn off the passenger’s airbag
unless the person sitting there is in a risk
group identied by the national
government. SeeAirbag Off Switch on
page 95for more on this, including
important safety information.
{CAUTION:
If the airbag readiness light ever comes
on when you have turned off the airbag, it
means that something may be wrong with
the airbag system. The right front
passenger’s airbag could inate even
though the switch is off. If this ever
happens, do not let anyone whom the
national government has identied as a
member of a passenger airbag risk group
sit in the right front passenger’s position
(for example, do not secure a rear-facing
child restraint in the right front
passenger’s seat) until you have your
vehicle serviced. SeeAirbag Off Switch on
page 95andAirbag Readiness Light on
page 252for more on this, including
important safety information.
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If the word ON or the on symbol is lit, it means
that the right front passenger’s frontal airbag
is enabled (may inate). SeeAirbag Off Switch on
page 95for more on this, including important
safety information.
If, after several seconds, both status indicator
lights remain on, or if there are no lights at
all, there may be a problem with the lights or the
airbag on-off switch. See your dealer/retailer
for service.
Passenger Airbag Status Indicator
If your vehicle has the passenger sensing system,
your overhead console will have a passenger
airbag status indicator.When you start the vehicle, 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).
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If, after several seconds, both 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/retailer for service.
{CAUTION:
If the airbag readiness light in the
instrument panel cluster ever comes on
and stays on, 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’s seat
may not have the protection of the
airbag(s). SeeAirbag Readiness Light on
page 252for more on this, including
important safety information.
Charging System Light
If this light comes on
when the engine is
running, there could be
a problem with the
charging system.
This light will also stay on while the key is in RUN
until the engine is started.
If the light stays on after starting the engine 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 the battery.
If you must drive a short distance with this light
on, it helps to turn off all of the electrical
accessories, such as the radio and the blower.
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Voltmeter Gage
Your vehicle may have
a voltmeter gage.
When the ignition is in RUN, this gage indicates
the battery voltage.
When the engine is running, this gage shows the
condition of the charging system. The gage
may transition from a higher to lower or a lower to
higher reading, this is normal. If the vehicle is
operating outside the normal operating range, thecharging system light will come on. SeeCharging
System Light on page 256for more information.
The voltmeter gage may also read lower when in
fuel economy mode. This is normal.
Readings outside the normal operating range may
also occur when a large number of electrical
accessories are operating in the vehicle and the
engine is left idling 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 readings
outside the normal operating range. If you must
drive, turn off all unnecessary accessories.
Readings outside the normal operating range
indicate a possible problem in the electrical system.
Have the vehicle serviced as soon as possible.
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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.
This light may also come on due to low brake
uid. SeeBrakes on page 529for 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 441.
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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 258.
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.
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