Remedy: If the RAM DIMM is installed, remove it and turn off the power of the printer and back on. Replace the CU/PU board. Re-install the RAM DIMM. Replace the RAM DIMM.
Code: 020
Display: Service call 020: Error
Description: CU ROM Hash Check Error
Remedy: Turn off the power of the printer and back on. Replace the CU/PU board.
Code: 030
Display: Service call 030: Error
Description: CU RAM Check Error
Remedy: Turn off the power of the printer and back on. Replace the CU/PU board.