EPSON Stylus Pro 4400/4450/4800/4880/4880C Revision C
Troubleshooting Troubleshooting Based on Panel Messages 174
FATAL ERROR
The printer has failed. Because this cannot be recovered by the user, resolve by following "3.2.4 Corrective Actions for Service Request Display" (p.175).
LCD Explanation Recovery
SERVICE  REQ. nnnnnnnnn
("nnnnnnnnn" shows type of fatal 
error.)
Occurrence of any error from which the user can not recover the 
printer.
If cleared by turning power OFF and then ON again, continue using 
printer intermittently in that condition. If the same code for the fatal 
error is generated again, specify the cause of the problem and replace 
corresponding failed part causing the problem.
Life expiration of a long-life part which can cause secondary problems 
if the part is further used.
The printer has been brought into malfunction by unexpected 
operation or by receiving an unexpected command.