Lexmark CS720 Service Manual page 219

Actions
Step 4
Replace the controller board with a new, and not previously
installed, controller board. See
page 357.
Does the problem remain?
Step 5
a
Turn the printer off for ten or more seconds.
b
Turn the printer back on.
Does the problem remain?
Step 6
Clear the NVRAM of the printer:
a
Turn the printer off.
b
With the printer off, press and hold buttons 6, 7, and 8 on the
keypad.
c
Turn the printer on.
When Restoring Factory Defaults appears, release
d
the buttons.
Note: If the printer looks up on the Restoring Factory Defaults,
then wait two minutes, and then turn the printer off. After ten
seconds or more, turn the printer back on without holding down
any buttons.
Does the problem remain?
Step 7
Replace the control panel. See
page 280.
Does the problem remain?
Step 8
Replace the controller board. See
page 357.
Does the problem remain?
"Controller board removal" on
"Upper control panel removal" on
"Controller board removal" on
Diagnostic information
219
Yes No
Go to step 5. The problem is
solved.
Go to step 6. The problem is
solved.
Go to step 7. The problem is
solved.
Go to step 8. The problem is
solved.
Contact the next The problem is
level of support. solved.
5028