Hi.
There are several ways to reset the unit to factory. Replacing the RAM will not reset the unit to factory. Replacing the NVRAM is clearly not a viable solution, unless the NVRAM is defective.
One way to reset the printer is by using the dip switch located on the main board. To reset to factory the dip switch array marked S1 below must be set to off off off on:
Change to dip switch is done in this way:
Note original dip switch combination.
Disconnect power.
Set switches as above- DO NOT TRY ANY OTHER COMBINATION
Restart printer.
Turn off.
Disconnect power.
Put switch in original combination.
Restart again.
If you repute this solution helpful, then please do not forget to accept the solution.
Regards.