Lexmark CX725
Step 1
Update the firmware.
Note: Contact the next level of support for the correct firmware level.
Does the problem remain?
Go to step 2.
The problem is solved.
Step 2
Replace the controller board. See Controller board removal.
Contact the next level of support.
An “Invalid Engine Code” error message indicates a problem with one of the internal operating programs of the printer. The printer is not able to receive, and process print jobs until the printer is reset.
Lexmark CX/CS72x and XC/Cxxxx: Print Quality Diagnosis ? Printer Not Printing Black