Here is a list of error codes for the Sharp MX-copier, along with brief descriptions and potential causes​​:
A0 Series (PCU/SCN-MFP PWB Errors)
A0-01, A0-02, A0-04: PCU/SCN-MFP PWB ROM errors.
A0-10, A0-15, A0-17, A0-18, A0-20, A0-21, A0-22: Inconsistencies between firmware, EEPROM data, or PCU/SCN-MFP.
U1 Series (Battery/Memory Errors)
U1-01: Battery trouble.
U2-00, U2-11, U2-30, U2-41: MFP/SCN-MFP PWB EEPROM errors.
U2-05: Account data error.
E7 Series (Various Component Errors)
E7-01, E7-03, E7-04: HDD-related issues.
E7-10 to E7-29: LSU laser detection errors.
E7-40 to E7-48: Image data, ASIC, and watermarks.
E7-60 to E7-80: Communication issues between SCN-MFP PWB and other components.
C1 Series (Main Charger Issues)
C1-10, C1-14, C1-15, C1-16, C1-40, C1-41: Main charger trouble for monochrome and color.
F1 Series (Finisher Errors)
F1-00 to F1-03: Finisher motor and inlet transport errors.
F2 Series (Toner/Drum Sensor Errors)
F2-22 to F2-67: Discharge lamp and toner density sensor issues.
F2-70 to F2-78: Toner cartridge and registration image density sensor errors.
H Series (Thermistor Issues)
H2-00 to H2-03: Thermistor open troubles.
H3-00 to H3-02: Fusing section high-temperature troubles.
H4-00 to H4-02: Fusing section low-temperature troubles.
H7-10, H7-11: Fusing temperature recovery errors.
L Series (Motor/Fan Issues)
L1-00, L3-00, L4-02 to L4-43: Motor and fan troubles.
L6-10, L8-01 to L8-02: Polygon motor and full wave signal errors.
F3 Series (Paper Feed Tray Troubles)
F3-12, F3-22: Paper feed tray lift troubles.
F6 Series (FAX Issues)
F6-00 to F6-98: FAX control board and power supply troubles.
U7 Series (Vendor Machine Errors)
U7-50, U7-51: Vendor machine errors.
These are the major error codes for the Sharp MX-4070N. For a complete list and detailed troubleshooting information, consult the copier's service manual​​.