Agilent 7820 GC Service
217
Components can be damaged by static electricity:
be sure to wear an ESD strap grounded to the GC
chassis while performing this procedure.
Remove the right side electronics panel cover.
Disconnect the ribbon cable to the keyboard/display.
Disconnect the communications bus cable. If present, also
remove the external LAN cable.
Slide the logic board down while using a rocking motion to
unplug the board from its analog and power board receptacle.
With respect to the new logic board, verify, and if necessary
change, the battery-connect switch found next to the battery: The
switch must be in position away from the analog and power
board (see above).
If switches are incorrectly-set (battery
disconnected), critical internal GC information
will be lost any time AC power is not present.