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{CAUTION:
Four-wheel drive vehicles with the transfer
case in NEUTRAL will allow the vehicle to
roll, even if your shift lever is in PARK (P).
So, be sure the transfer case is in a drive
gear — not in NEUTRAL. Always set your
parking brake.
Follow the proper steps to be sure your vehicle
will not move. SeeShifting Into Park (P) on
page 139.
If you are pulling a trailer, seeTowing a Trailer
on page 414.
Mirrors
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, if
equipped, are at the bottom of the mirror.
SeeOnStar
®System on page 156for more
information about the services OnStar®provides.
P(On/Off):This is the on/off button.
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Temperature and Compass Display
Press the on/off button, located on the far left of
the mirror face, 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, do the
following:
1. Press and hold the on/off button 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, please see
your GM dealer. Under certain circumstances,
a delay in updating the temperature is normal.
Automatic Dimming Mirror Operation
The automatic dimming mirror function is turned
on automatically each time the ignition is started.
To operate the automatic dimming mirror, do
the following:
1. Make sure the green indicator light, located to
the left of the on/off button, is lit. If it is not,
press and hold the on/off button until the
green light comes on, indicating that the mirror
is in automatic dimming mode.
2. Turn off the automatic dimming mirror function
by pressing and holding the on/off button until
the green indicator light turns off.
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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, do the following:
1. Find your current location and variance
zone number on the following zone map.
2. Press and hold the on/off button untilaZand
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.
4. Calibrate the compass as described next.
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