My wife has the Gekko and the AC is that the Auto-on Contacts are wet but the computer hasn't entered dive mode yet, as many others in this thread have correctly stated.
Here is the Nitrox section from the Gekko manual.
"NOTE! The computer will automatically revert to
the air (21% O2) setting when a new dive series is
started, if it is not set to any other mix during the
last two hours. When the oxygen percentage is set
for air, the computer will retain this setting.
Manually entered values for oxygen percentage are
retained for about two hours after the setting if a
dive series has not started. In case a dive series is
started, the set value is retained until a new dive series
is started or a new value is entered manually."
Hope this clears things up for you...
Here is the Nitrox section from the Gekko manual.
"NOTE! The computer will automatically revert to
the air (21% O2) setting when a new dive series is
started, if it is not set to any other mix during the
last two hours. When the oxygen percentage is set
for air, the computer will retain this setting.
Manually entered values for oxygen percentage are
retained for about two hours after the setting if a
dive series has not started. In case a dive series is
started, the set value is retained until a new dive series
is started or a new value is entered manually."
Hope this clears things up for you...