FS-9120DN/9520DN 1-4-2 Maintenance mode (1) Maintenance mode The printer is equipped with a maintenance function which can be used to maintain and service the machine. To run the maintenance mode, Insert a compact flash card to which the API program has been written into the printer and load the API program to the printer using either method.
FS-9120DN/9520DN 1-5-2 Self-diagnosis (1) Self-diagnostic function This printer is equipped with a self-diagnostic function. When a problem is detected, printing is disabled. The problem is displayed as a code consisting of digits number followed by a number between 0100 and F080, indicating the nature of the problem.
Page 5
FS-9120DN/9520DN Remarks Code Contents Causes Check procedures/corrective measures 4200 BD steady-state problem Defective laser Replace the LSU (see page 1-6-11). • While the polygon motor is on, a BD diode. error is detected three times continu- Defective polygon Replace the LSU (see page 1-6-11).
Page 6
FS-9120DN/9520DN Remarks Code Contents Causes Check procedures/corrective measures Abnormally low fuser unit thermistor Broken fuser Check for continuity. If none, replace the 6050 temperature heater M or S fuser heater M or S (see page 1-6-20). • When only fuser heater M is on, fuser wire.