GMC 2007 Sierra - Manual (Page 180)

Automatic Dimming Rearview Mirror
with Compass and Temperature
Display
If the vehicle is equipped with an automatic mirror, it
will, when on, automatically dim to the proper level
to minimize glare from lights behind you after dark.
The mirror also includes a 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. The dual
display can be turned on or off by briefly
pressing either the TEMP or the COMP button.
Temperature Display
The temperature can be displayed by pressing the
TEMP button. Pressing the TEMP button once
briefly, will toggle the temperature reading on and
off. To alternate the temperature reading
between Fahrenheit and Celsius, press and hold
the TEMP button for approximately four seconds
until the display blinks F and C. Press and release
the TEMP button to toggle between the Fahrenheit
and Celsius readings. After approximately four
seconds of inactivity, the display will stop blinking
and display the last selection made.
If an abnormal 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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