CHEVROLET Tahoe - Manual (Page 167)

Automatic Dimming Mirror Operation
O : 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
briefly to turn the display on or off.
Compass Calibration
The compass may need calibration if one of the
following occurs:
• If CAL is displayed while driving in the vehicle.
• After approximately five seconds, the display
does not show a compass heading, N for
North, for example, there may be a strong
magnetic field 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 in the compass/temperature button for
approximately nine 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 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.
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