CHEVROLET TRAIL BLAZER 2008 1.G Owners Manual
Manufacturer: CHEVROLET, Model Year: 2008, Model line: TRAIL BLAZER, Model: CHEVROLET TRAIL BLAZER 2008 1.GPages: 472, PDF Size: 2.57 MB
Page 111 of 472

Compass Variance
Compass variance is the difference between earth’s
magnetic north and true geographic north. The mirror is
set to zone eight upon leaving the factory. It will be
necessary to adjust the compass to compensate
for compass variance if you live outside zone eight.
Under certain circumstances, such as during a
long distance cross-country trip, it will be necessary to
adjust for compass variance. If not adjusted to
account for compass variance, your compass could give
false readings.
To adjust for compass variance:
1. Find your current location and variance zone
number on the following zone map.
2. Press and hold the on/off button until the zone
number is displayed. The number shown is the
current zone number.
3. Scroll through the zone numbers that appear in the
window on the mirror by pressing the on/off button.
Once you nd your zone number, release the button.
After about four seconds, the mirror will return to the
compass display, and the new zone number will be
set. If C or CAL appears in the compass window, the
compass may need calibration. See “Compass
Calibration” listed previously.
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Page 112 of 472

Automatic Dimming Rearview Mirror
with OnStar
®, Compass and
Temperature Display
Your vehicle may have this feature. When on, an
automatic dimming mirror automatically dims 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 face. The compass reading and
the outside temperature will both appear in the display
at the same time.
P(On/Off):This is the on/off button.
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’s 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.
Temperature and Compass Display
Press the on/off button, located to the far left, brie y to
turn the compass/temperature display on or off.
If the display reads CAL, you will need to calibrate the
compass. For more information on calibration, see below.
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 display will return.
If an abnormal temperature reading is displayed for an
extended period of time, please consult your dealer.
Under certain circumstances, a delay in updating
the temperature is normal.
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Page 113 of 472

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 you live 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, your 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 until a Z and a
zone number appear 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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