HI Sandman,
i been fix lot 3650 ,, not charging, not RX TX possible ,, it is becasue some flash tool earse EEPROM ELEMENT 1 area
!
just need to do by use JBV-1 or FLA-x to make energy calibration under phoenix !
about 7650, check BSI and BTEMP pin when you plug a charger
Willy