Description: Option unit for different model detected.
Remedy: Is a proper option unit for the printer set? Set proper option unit. Check connections and turn power ON. If error is not recovered, replace the unit.
Code: 120
Display: Service Call 120: Error
Description: PU unit fan motor error.
Remedy: 1) Is fan in PU unit operating? 2) Error reoccurs after replacing fan motor. Replace fan motor. Replace engine control board. Replace engine control board.
Code: 121
Display: Service Call 121: Error
Description: High-voltage power supply I/F error.
Remedy: Is cable between PU board andhighvoltage power LSI connected properly? Connect properly. Replace high-voltage power supply. Check improper connections for high-voltage.