2008 GMC SIERRA mirror

Follow the proper steps to be sure your vehicle will not
move. SeeShifting Into PARK (P) on page 2-50.
If you are pulling a trailer, seeTowing a Trailer on
page 4-55.
Mirrors
Manual Rearview Mirror
When you are sitting in a comfortable driving position,
adjust the mirror so you can see clearly behind your
vehicle. Hold the mirror in the center to move it up or
down and side to side. The day/night adjustment allows
you to adjust the mirror to avoid glare from the lamps
behind you. Push the tab forward for daytime use
and pull it for nighttime use.
Automatic Dimming Rearview Mirror
with OnStar
®, Compass and
Temperature Display
Your vehicle may have this feature. When on, the
automatic dimming mirror dims to the proper level to
minimize glare from lights behind you after dark.
The mirror has a dual display in the upper right corner
of the mirror face that shows the compass reading
and the outside temperature.Control buttons for the OnStar
®system are at the
bottom of the mirror. SeeOnStar®System on page 2-65
for more information about the services OnStar®
provides.
P(On/Off):This is the on/off button.
Temperature and Compass Display
Press the on/off button, located to the far left, briey to
turn the compass/temperature display on or off.
If the display reads CAL, the compass needs to be
calibrated. For more information, see “Compass
Calibration” following.
To adjust between Fahrenheit and Celsius:
1. Press and hold the on/off button for approximately
four seconds until either a ashing F or C appears.
2. Press the button again to change the display to the
desired unit of measurement. After approximately
four seconds of inactivity, the new unit will be locked
in and the compass/temperature display will
return.
If an abnormal temperature reading is displayed for an
extended period of time, see your dealer/retailer.
Under certain circumstances, a delay in updating the
temperature is normal.
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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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2. Press and hold the on/off button until a Z and a
zone number appears in the display. The compass
is now in zone mode.
3. Keep pressing the on/off button until the desired
zone number appears in the display. Release the
button. After approximately four seconds of
inactivity, the new zone number will be locked in
and the compass/temperature display will return.
Cleaning the Mirror
When cleaning the mirror, use a paper towel or similar
material dampened with glass cleaner. Do not spray
glass cleaner directly on the mirror as that may cause
the liquid cleaner to enter the mirror housing.
Automatic Dimming Rearview Mirror
with Compass and Temperature
Display
Your vehicle may have this mirror. When on, an
automatic dimming mirror will dim to the proper level to
minimize glare from lights behind you after dark.
The mirror also includes a dual display in the upper
right corner of the mirror with the compass reading and
the outside temperature.
Yb:Briey press this button to turn the display on
or off.
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Temperature Display
The temperature can be displayed by pressing the
compass/temperature button. Pressing the compass/
temperature button once briey, will toggle the display
reading on and off. To alternate the temperature reading
between Fahrenheit and Celsius, press and hold the
compass/temperature button for approximately
three seconds until the display blinks F and C. After
approximately ve seconds of inactivity, the display will
stop blinking and display the last selection made.
If an abnormal temperature reading is displayed for
an extended period of time, see your dealer. Under
certain circumstances, a delay in updating the
temperature is normal.
Automatic Dimming Mirror Operation
O
On/Off:Press this button to turn the automatic
dimming feature on or off. The indicator light to the left
of the button will turn on to indicate when the feature
is on. Once the mirror is turned off, it will remain off until
it is turned back on, or until the vehicle is restarted.
Compass Operation
Press the compass/temperature button once briey to
turn the display on or off.
Compass Calibration
See “Compass Calibration” underAutomatic Dimming
Rearview Mirror with OnStar®, Compass and
Temperature Display on page 2-55for more information.
Compass Variance
See “Compass Variance” underAutomatic Dimming
Rearview Mirror with OnStar®, Compass and
Temperature Display on page 2-55for more information.
Cleaning the Mirror
Use a paper towel or similar material dampened with
glass cleaner. Do not spray glass cleaner directly on the
mirror as that may cause the liquid cleaner to enter
the mirror housing.
Outside Manual Mirrors
Adjust your outside mirrors so you can just see the side
of your vehicle and have a clear view of objects behind
you. The mirrors can be folded in to enter narrow areas.
The use of hood-mounted air deectors and add-on
convex mirror attachments may adversely affect mirror
performance.
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Outside Trailer-Tow Mirrors
If your vehicle has trailer towing type mirrors, they can
be adjusted so you can have a clear view of the
objects behind you. Manually pull out the mirror head to
extend it for better visibility when towing a trailer.
These mirrors can be manually folded forward or
rearward. The lower portion of the mirror is convex. A
convex mirror’s surface is curved so you can see
more from the driver’s seat. The convex mirror can be
adjusted manually to the driver’s preferred position
for better vision.
Your vehicle may have outside heated mirrors which
help clear them of condensation, snow, and ice. When
the rear window defogger button is pressed, the
heated mirrors are also turned on. Only the upper glassof the mirror is heated. The lower convex part of the
mirror is not heated.
Your mirror may also have a turn signal arrow that will
ash in the direction of the turn or lane change.
Outside Power Mirrors
If your vehicle is equipped
with outside power mirrors,
the controls are located
on the driver’s door
armrest.
Press (A) to select the driver’s side mirror. Then
press the arrows located on the four-way control
pad to adjust the mirror. Press (A) again to deselect
the mirror.
Press (B) to select the passenger’s side mirror.
Then press the arrows located on the four-way
control pad to adjust the mirror. Press (B) again to
deselect the mirror.
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This mirror has the following features.
Manual Folding
The mirrors can be manually folded inward to prevent
damage when going through an automatic car wash. To
fold, push the mirror toward the vehicle. To return the
mirror to its original position, push outward. Be sure
to return both mirrors to their original unfolded position
before driving.
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
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.
{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.
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Outside Power Foldaway Mirrors
If your vehicle is equipped
with outside power
foldaway mirrors, the
controls are located on the
driver’s door armrest.
Press (A) to select the driver’s side mirror. Then
press the arrows located on the four-way control
pad to adjust the mirror. Press (A) again to deselect
the mirror.
Press (B) to select the passenger’s side mirror.
Then press the arrows located on the four-way
control pad to adjust the mirror. Press (B) again to
deselect the mirror.
Press (C) to fold the mirrors out to the driving
position.
Press (D) to fold the mirrors in to the folded
position.If the mirrors are accidentally folded/unfolded manually,
they may shake or utter at normal driving speeds
and may not stay in the unfolded position. If this
happens, you will need to reset the mirrors. See
“Resetting the Power Foldaway Mirrors” next.
Resetting the Power Foldaway Mirrors
You will need to reset the power foldaway mirrors if the
following occurs:
The mirrors are accidentally obstructed while
folding.
They are accidentally manually folded/unfolded.
The mirrors will not stay in the unfolded position.
The mirrors shake and utter at normal driving
speeds.
To reset the power foldaway mirrors, fold and unfold
them one time using the mirror controls. This will reset
them to their normal position.
This mirror has the following features.
Automatic Dimming
The driver’s outside mirror will adjust for the glare of the
headlamps behind you. SeeAutomatic Dimming
Rearview Mirror with OnStar
®, Compass and
Temperature Display on page 2-55.
2-61

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.
2-62