The internal battery is a lithium button battery which will fail after 5 to 10 years. When it fails the unit's electronic security seal and settings and files will be lost. It is pretty easy to replace the battery, but you should have an LX Navigation dealer like myself do it because there are several similar batteries and you don't want to change the wrong one. Also, only a dealer can re-seal the unit for you. I can change the battery and re-seal it here for $30. I can recalibrate the logger altimeter for an additional $95, plus return shipping costs.

Best Regards,

Paul Remde
Cumulus Soaring, Inc.

On Monday, April 2, 2018 at 3:26:58 AM UTC-5, wrote:
There does not appear to be anything wrong with the integrated flash memory
but has anbody had problems with the internal RAM backup power battery
failing on this unit?