Nvram Mismatch Failure Service Check - Konica Minolta bizhub 4020 Service Manual

Error code Description
956.xx Controller board failure—processor failure.
Replace the controller board.
956.01 Processor Overtemp.
Replace the controller board.
957.xx Controller board failure—ASIC failure.
Replace the controller board.
958.xx Controller Board NAND Failure—printer has
performed more than 100 shift and reflash
operations as a result of ECC bit corrections.
Replace the controller board.

NVRAM mismatch failure service check

Warning—Potential Damage: When replacing any of the following components:

Control panel assembly

Controller board assembly
Replace only one component at a time. Replace the required component and perform a POR before
replacing a second component listed above. If this procedure is not followed, the printer will be
rendered inoperable. Never replace two or more of the components listed above without a POR after
installing each one or the printer will be rendered inoperable.
Warning—Potential Damage: These components can be used as a method of troubleshooting as long
as the machine is booted into diagnostic mode or is operating in diagnostic mode. Once a component
has been installed in a machine and powered up into user mode, it cannot be used in another machine.
It must be returned to the manufacturer.
Action
Step 1
Check the control panel assembly.
Was the control panel assembly recently replaced?
Step 2
Check the controller board assembly.
Was the controller board assembly recently replaced?
Step 3
Replace the current control panel assembly with the original
control panel assembly. Go to
Does the error remain?
bizhub 4020/3320 Service Manual
Control panel assembly removal.
- 139 -
Action
Go to Controller board removal.
Go to Controller board removal.
Go to Controller board removal.
Go to Controller board removal.
Yes No
Go to step 3. Go to step 2.
Go to step 4. Contact next level of
support.
Go to step 5. The problem is
solved.