121 Errors - Lexmark MS312 Service Manual

Action
Step 6
Check the LSU for damages, and replace if necessary.
Installation note: Mechanical and electronic LSU adjustments
are required to complete the installation of the LSU. See
"Printhead assembly adjustments" on page
Does the problem remain?
Step 7
Check the LSU and controller board connector for damaged or
bent pins. Replace the part with damaged pins.
Does the problem remain?
Step 8
Replace the controller board.
Does the problem remain?

121 errors

121 error messages
Error code Description
121.07 Fuser has been on for more than allowed after a
gap blowout, and the temperature is still too cold.
121.08 Fuser was under temp when page was in fuser.
121.20 Fuser undertemp during steady state control. Can
occur in printing or standby modes.
121.22 Fuser did not warm enough to start line voltage
detection.
121.23 Fuser took too long to heat to line detection temp.
121.24 Fuser never reached detection temperature.
121.25 After line voltage detection, control did not roll
over to steady state control in time.
121.26 Failed to reach temperature during warm up.
121.28 Failed to reach EP warm up temperature in time.
121.29 Fuser failed to reach pre‑heat temperature for
motor start during warm up.
204.
Action
Go to
Diagnostics and troubleshooting
126
Yes No
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.
"Fuser service check" on page
4514-330
127.