GMC 1999 Jimmy Owner's Manual page 122

Temperature and Compass Display
The outside air temperature and the compass are
displayed at the front of the overhead console. The
control switches are located to the left of the display.
Turn the display on or off by pressing the ON/OFF
switch. Display the temperature in either degrees
Fahrenheit (English) or Celsius (metric) by pressing the
US/MET switch.
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Before you turn on the ignition and move the vehicle,
the temperature indicated will be the last outside
temperature recorded with the ignition on.
If the outside temperature is 37 _ F (3 _ C) or lower when
you turn on the ignition, ICE will appear on the display.
This is a warning to the driver that road conditions may
be icy, and that appropriate precautions should be taken.
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The compass is self calibrating, so it does not need to be
manually set. However, when your vehicle is new, the
compass may function erratically. If it does, CAL
(Calibration) will appear on the display. To correct the
problem, drive in a complete 360 _ circle three times,
and the compass will function normally.
Variance is the difference between magnetic north and
geographic north. In some areas, the difference between
the two can be great enough to cause false compass
readings. If this happens, follow these instructions to set
the variance for your particular location:
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