SUUNTO COBRA3 User Guide - Manual (Page 48)

If the battery symbol is displayed in the Surface mode, or if the display is faded or
weak, the battery may be too low to operate the dive computer, and battery replacement
is recommended.
NOTE
For safety reasons, the backlight cannot be activated when the
low battery warning is indicated by the battery symbol.
5.8.4. Diving at altitude
The dive computer can be adjusted both for diving at altitude and also to increase the
conservatism of the mathematical nitrogen model.
When programming the instrument for the correct altitude, you need to select the
correct Altitude Adjustment settings according to Table 5.4, Altitude Adjustment settings.
The dive computer will adjust its mathematical model according to the entered altitude
setting, giving shorter no-decompression times at higher altitudes.
For more information, see Section 10.2.3. Altitude diving.
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