Suunto D4 manual Battery Replacement, By the warranty

9. BATTERY REPLACEMENT

NOTE	It is advisable to contact an authorized Suunto representative for
	battery replacement. It is imperative that the change is made in
	a proper manner to avoid any leakage of water into the battery
	compartment or computer.
CAUTION	Defects caused by improper battery installation are not covered
	by the warranty.
CAUTION	When the battery is changed, all nitrogen and oxygen uptake data
	is lost. Therefore, the no-fly time shown by the computer should
	have reached zero or you must wait for 48 hours, or preferably
	up to 100 hours, before you dive again.

All history and profile data, as well as the altitude, personal, and alarm settings, will remain in the dive computer memory after the battery change. However, the clock time and time alarm settings are lost. In the NITROX Mode, the nitrox settings also revert back to default settings (MIX1 21 % O2, 1.4 bar PO2).

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