Panasonic KX-PS8100 - Manual (Page 274)

274
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To replace the printer controller board:
1 Align the printer controller board with the groove on the
back of the printer and carefully slide it back inside the
printer.
2 Tighten the two screws on the printer controller board
that you loosened earlier, using a cross-point head (+)
screwdriver.
3 Plug in the power cord and reconnect any cables to the
back of the printer.
Printer controller board