Ricoh M281 Series Service Manual page 334

Electrical Components
6. Remove the controller board [A] from the BiCU [B].
7. Remove the two guide rails [A] from the controller board [B]. (hook×2)
8. Remove the two NVRAMs [A] from the old controller board and install them on the new
controller board.

Make sure the NVRAM [A] is installed at the correct mounting location and orientation.
Install the NVRAM so that the indentation on the NVRAM corresponds with the mark [B]
on the controller board.

Incorrect installation of the NVRAM will damage both the controller board and NVRAM.
D255/D256/M281/M282 4-140 SM