Chevrolet 2003 Blazer Owner's Manual page 120

Variance is the different 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:
1. Find your location on the zone map. Record your
zone number.
3. After five seconds, the compass will acknowledge
the variation mode by displaying the current zone
number. When it does, release both buttons.
the display.
variance is now set and the display will return to the
COMP/TEMP mode.
4. Press US/MET until your zone number appears on
5. Press MODE to set your zone number. Your
TRIP: Once in the TRIP mode, pressing the MODE
button will step you through the following trip functions:
AVG ECON (Average Economy): The average fuel
economy since the last reset is displayed.
INST ECON (Instantaneous Economy): Instantaneous
fuel economy for the last second of driving is displayed.
RANGE: The display indicates the estimated distance
that can be travelled with the remaining fuel in the tank,
based on the fuel economy for the last few hours of
driving.
FUEL USED: The fuel used since the last reset is
displayed.
AVG SPEED (Average Speed): The average speed
since the last reset is displayed.
2. Press and hold both the MODE and the US/MET
buttons in the COMP/TEMP mode.
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