Volvo 2008 C30 Owner's Manual page 66

The compass may need to be calibrated in certain cases. If calibration is required, the character C appears in the mirror's
display.
The earth is divided into 15 magnetic zones. The compass is initially set for the zone to which the vehicle was delivered,
and should always be adjusted if the vehicle is driven to a new magnetic zone. A "C" will be displayed if calibration
becomes necessary.
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02 Instruments and controls
Mirrors
To calibrate the compass:
1. Stop the vehicle in a large, open area, away from traffic.
2. Using a pen or similar object, hold the button (1) depressed for at least 6 seconds. "C" will be displayed.
3. Press button (1) for at least 3 seconds to display the number of the current magnetic zone.
4. Press button (1) repeatedly until the number for the required geographical area (1-15) is displayed. "C" will be
displayed again.
5. Drive slowly in a circle at a maximum speed of 6 m.p.h. (10 km/h) until a compass direction is displayed.
Calibration is complete.
Magnetic zones
74
02 Instruments and controls
Mirrors
Power door mirrors