2008 GMC SIERRA ignition

Shifting Out of PARK (P)
This vehicle is equipped with an electronic shift lock
release system. The shift lock release is designed to:
Prevent ignition key removal unless the shift
lever is in PARK (P) with the shift lever button fully
released, and
Prevent movement of the shift lever out of
PARK (P), unless the ignition is in ON/RUN or
ACC/ACCESSORY and the regular brake pedal is
applied.
The shift lock release is always functional except in the
case of an uncharged or low voltage (less than
9 volt) battery.If your vehicle has an uncharged battery or a battery
with low voltage, try charging or jump starting the
battery. SeeJump Starting on page 5-46for more
information.
To shift out of PARK (P) use the following:
1. Apply the brake pedal.
2. Move the shift lever to the desired position.
If you still are unable to shift out of PARK (P):
1. Ease the pressure on the shift lever.
2. While holding down the brake pedal, press the shift
lever all the way into PARK (P).
3. Move the shift lever to the desired position.
If you are still having a problem shifting, then have your
vehicle serviced soon.
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Automatic Dimming Mirror Operation
The automatic dimming mirror comes on each time the
ignition is turned to start. To turn the automatic
dimming feature off or back on, press the on/off button.
The indicator light on the mirror is lit when the
automatic dimming feature is on.
Compass Calibration
The compass may need calibration if one of the
following occurs:
After approximately ve seconds, the display does
not show a compass heading, N for North, for
example, there may be a strong magnetic eld
interfering with the compass. Such interference may
be caused by a magnetic antenna mount, magnetic
note pad holder, or a similar magnetic item.
The compass does not display the correct heading
and the compass zone variance is set correctly.
In order to calibrate, CAL must be displayed in the
mirror compass windows. If CAL is not displayed, push
the on/off button for approximately 12 seconds or
until CAL is displayed.The compass can be calibrated by driving the vehicle in
circles at 5 mph (8 km/h) or less until the display
reads a direction.
Compass Variance
The mirror is set in zone eight upon leaving the factory.
It will be necessary to adjust the compass to
compensate for compass variance if the vehicle is
outside of zone eight. Under certain circumstances, as
during a long distance cross-country trip, it will be
necessary to adjust for compass variance. Compass
variance is the difference between earth’s magnetic
north and true geographic north. If not adjusted
to account for compass variance, the compass could
give false readings.
To adjust for compass variance:
1. Find your current location and variance zone
number on the following zone map.
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Park Tilt Mirrors
If your vehicle has the memory package, the outside
mirrors are able to perform the park tilt function. This
feature may be useful in allowing the driver to view the
curb when parallel parking. This feature will cause the
passenger’s and/or driver’s mirror to tilt to a preselected
position when the vehicle is in REVERSE (R).
The passenger’s and/or driver’s mirror will return to its
original position when the vehicle is shifted out of
REVERSE (R), or the ignition is turned off or to
OFF/LOCK.
This feature can be turned on or off through the Driver
Information Center (DIC). SeeDIC Vehicle
Customization (With DIC Buttons) on page 3-72.
Heated Mirrors
The button to turn the heated mirrors on or off is located
on the climate control panel. Press this button to
warm the driver’s and passenger’s outside rearview
mirrors to help clear them of ice, snow, and
condensation.
See “Rear Window Defogger” underDual Automatic
Climate Control System on page 3-28for more
information.
Convex Mirror
{CAUTION:
A convex mirror can make things (like other
vehicles) look farther away than they really are.
If you cut too sharply into the right lane, you
could hit a vehicle on your right. Check your
inside mirror or glance over your shoulder
before changing lanes.
The passenger’s side mirror may have convex glass. A
convex mirror’s surface is curved so more can be
seen from the driver’s seat.
Your vehicle may also have a turn signal indicator on
the mirror. An arrow on the mirror will ash in the
direction of the turn or lane change.
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Sunroof
If your vehicle has a power sliding sunroof, the ignition
needs to be turned to RUN, or the Retained Accessory
Power (RAP) must be activated to open or close
the sunroof. When RAP is active, the sunroof will work
for 10 minutes after the ignition is turned off, or until
the driver’s door is opened. SeeRetained Accessory
Power (RAP) on page 2-23for more information.
Extended Cab
If your vehicle is an
extended-cab, the sunroof
switch is located on the
headliner above the
rearview mirror.
Vent:From the closed position, press and hold the rear
of the switch to vent the sunroof. To close the sunroof,
press and hold the front of the switch.Open:From the vent position, the sunroof can be fully
opened either manually or by using the express-open
feature. To open manually, press the rear of the switch
to the rst depression and hold until the sunroof has
reached the desired position. To open using
express-open, press the rear of the switch fully and
release. The sunroof will move to the full open position.
To stop the sunroof partway, press the switch a
second time.
Close:From the vent, or open position, press and hold
the front of the switch to close the sunroof.
The sunroof also has a roller sunshade that can be
used to block the rays of the sun. The roller sunshade
can be manually operated with the sunroof in an open or
closed position. To open the sunshade, press and
unlatch it, and roll it back. To close, pull it forward and
latch it into the closed position.
When the sunroof is opened, an air deector will
automatically raise. The air deector will retract when
the sunroof is closed.
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Hazard Warning Flashers
The hazard warning ashers warn others. They also let
police know you have a problem.
The hazard warning
asher button is located
on top of the steering
column.
Press the button to make the front and rear turn signal
lamps ash on and off. Press the button again to
turn the ashers off.The hazard warning ashers work no matter what
ignition position the key is in, and even if the key is not
in the ignition.
When the hazard warning ashers are on, your vehicle’s
turn signals will not work.
Other Warning Devices
If you carry reective triangles, you can set them up at
the side of the road about 300 feet (100 m) behind
your vehicle.
Horn
To sound the horn, press the horn symbols located on
the steering wheel.
3-8

Erasing Speed Memory
When the cruise control or the ignition is turned off, the
cruise control set speed memory is erased.
Exterior Lamps
The exterior lamps control
is located on the
instrument panel to the left
of the steering wheel.
It controls the following systems:
Headlamps
Taillamps
Parking Lamps
License Plate Lamps
Instrument Panel LightsThe exterior lamps control has four positions:
O(Off):Turn the control to this position to turn off the
automatic headlamps and daytime running lamps
(DRL). Turn the headlamp control to the off position
again to turn the automatic headlamps or DRL back on.
For vehicles rst sold in Canada, the off position will
only work when the vehicle is shifted into PARK (P).
AUTO (Automatic):Turn the control to this position to
automatically turn on the headlamps at normal
brightness, together with the following:
Parking Lamps
Instrument Panel Lights
Taillamps
License Plate Lamps
When the vehicle is turned off and the headlamps are in
AUTO, the headlamps may automatically remain on
for a set time. The time of the delay can be changed
using the DIC. SeeDriver Information Center (DIC) on
page 3-54.
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;(Parking Lamps):Turn the control to this position
to turn on the parking lamps together with the
following:
Instrument Panel Lights
Taillamps
License Plate Lamps
2(Headlamps):Turn the control to this position to
turn on the headlamps together with the following:
Parking Lamps
Instrument Panel Lights
Taillamps
License Plate Lamps
When the headlamps are turned on while the vehicle is
on, the headlamps turn off automatically 10 minutes
after the ignition is turned off. When the headlamps are
turned on while the vehicle is off, the headlamps will
stay on for 10 minutes before automatically turning off to
prevent the battery from being drained. Turn the
headlamp control to off and then back to the headlamp
on position to make the headlamps stay on for an
additional 10 minutes.
Push the turn signal/multifunction lever toward the
instrument panel to change the headlamps from low
beam to high beam.
Headlamps on Reminder
A reminder chime will sound when the headlamps or
parking lamps are manually turned on and your ignition
is off and a door is open. To disable the chime, turn
the light off.
Daytime Running Lamps (DRL)
Daytime Running Lamps (DRL) can make it easier for
others to see the front of your vehicle during the
day. DRL can be helpful in many different driving
conditions, but they can be especially helpful in the short
periods after dawn and before sunset. Fully functional
daytime running lamps are required on all vehicles
rst sold in Canada.
The DRL system will come on when the following
conditions are met:
The ignition is on.
The exterior lamps control is in AUTO.
The transmission is not in PARK (P).
The light sensor determines it is daytime.
When the DRL are on, only the DRL lamps will be on.
The taillamps, sidemarker, and other lamps will not
be on. The instrument panel will not be lit up either.
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When it begins to get dark, the automatic headlamp
system will switch from DRL to the headlamps.
To turn off the DRL lamps, turn the exterior lamps
control to the OFF position and then release. For
vehicles rst sold in Canada, the transmission must be
in the PARK (P) position, before the DRL lamps can
be turned off.
Automatic Headlamp System
When it is dark enough outside, the automatic headlamp
system will turn on the headlamps at the normal
brightness, along with the taillamps, sidemarker, parking
lamps, and the instrument panel lights. The radio
lights will also be dim.
To turn off the automatic headlamp system, turn the
exterior lamps switch to the off position and then release
it. For vehicles rst sold in Canada, the transmission
must be in the PARK (P) position, before the automatic
headlamp system can be turned off.
The vehicle has a light sensor located on the top of the
instrument panel in the defroster grille that regulates
when the automatic headlamps turn on. Be sure it is not
covered, or the headlamps will come on whenever
the ignition is on.
The system may also turn on the headlamps when
driving through a parking garage, heavy overcast
weather, or a tunnel. This is normal.There is a delay in the transition between the daytime
and nighttime operation of the Daytime Running
Lamps (DRL) and the automatic headlamp systems so
that driving under bridges or bright overhead street
lights does not affect the system. The DRL and
automatic headlamp system will only be affected when
the light sensor detects a change in lighting lasting
longer than the delay.
If the vehicle is started in a dark garage, the automatic
headlamp system will come on immediately. Once
the vehicle leaves the garage, it takes approximately
one minute for the automatic headlamp system to
change to DRL if it is bright enough outside. During that
delay, the instrument panel cluster may not be as
bright as usual. Make sure the instrument panel
brightness control is in the full bright position. See
Instrument Panel Brightness on page 3-21.
To idle the vehicle with the automatic headlamp system
off, turn the control to the off position.
The headlamps will also stay on after you exit the
vehicle. This feature can be programmed using the
Driver Information Center (DIC). SeeDIC Vehicle
Customization (With DIC Buttons) on page 3-72.
The regular headlamp system can be turned on
when needed.
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