OKI B721 Error Codes list and solutions

OKI B721 Error Codes list and solutions

– Compatible Printer model: OKI B721
– OKI B721 Error Code description:

• Code: 042, 043, 045
• Description: Flash File System Error
  Failed access to Flash set directly on PU/CU board.
• Troubleshooting Guides: Run forced initialization of Flash.(Note that NIC- F/W and Mac address is deleted.After the initialization,it is need to download NIC-F/W and / or Mac address by Maintenance utility.)Press’+”,’- ”,’CAN-CEL”to turn power ON . Replace the PU/CU board if symptom does not change.

• Code: 049
• Description: LED head type (resolution) error
  LED Head type was mismatched with CU and Engine.
• Troubleshooting Guides: 1) Replace the PU/ CU board with the one for the proper head. 2) Replace with a head of proper resolution.

• Code: 051
• Description: CU Fan Error Abnormal CPU cooling fan on PU/ CU board.
• Troubleshooting Guides: Connect Properly. Replace fan. Replace the PU/ CU board.

• Code: 052
• Description: DMA Abort Error detected in Image processor.
• Troubleshooting Guides: Power Off/On. Replace the PU/ CU board.

• Code: 067
• Description: SleepMode Interface Monitor I/F error with CU F/W.
• Troubleshooting Guides: Power Off/On. Replace the PU/ CU board.

• Code: 069
• Description: The NIC device had not worked correctly.
• Troubleshooting Guides: Power Off/On Replace the PU/ CU board.

• Code: 070
• Description: PSE firmware fault was detected.
• Troubleshooting Guides: Power Off/On. Replace the PU/ CU board.

• Code: 072
• Description: Engine I/F error between PU-CU.
• Troubleshooting Guides: Power Off/On. Replace the PU/ CU board.

• Code: 073
• Description: Video Error; Fault detected when image data was extended.
• Troubleshooting Guides: Power Off/On. Replace the PU/ CU board

• Code: 075
• Description: Video Error; Fault detected when image data was extended.
• Troubleshooting Guides: Power Off/On. Replace the PU/ CU board.

• Code: 077
• Description: The video decompress fault was detected on the image data expansion.
• Troubleshooting Guides: Replace the PU/ CU board

• Code: 081
• Description: The CU initializer detected an error in the backuped data.
• Troubleshooting Guides: Power Off/On. Replace the PU/ CU board.

Solve OKI B721 Error codes

• Code: 104
• Description: Engine EEPROM setting check was OK when power ON. Then detect read/ write error.
• Troubleshooting Guides: Power Off/On. Replace the PU/ CU board

• Code: 106
• Description: Abnormal engine control logic.
• Troubleshooting Guides: Power Off/On. Replace the PU/ CU board.

• Code: 112
• Description: Detected illegal 2nd Tray.
• Troubleshooting Guides: Is a 2nd Tray provided for this model installed? No Install a correct 2nd Tray.

• Code: 113
• Description: Detected illegal 3rd Tray.
• Troubleshooting Guides: Is a 3rd Tray provided for this model installed? No Install a correct 3rd Tray.

• Code: 114
• Description: Detected illegal 4th Tray.
• Troubleshooting Guides: Is a 4th Tray provided for this model installed? No Install a correct 4th Tray.

• Code: 121
• Description: High-voltage power supply I/F error.
• Troubleshooting Guides: Is cable between PU board and high-voltage power unit connected properly? Is there no improperly connections? No Yes No Connect properly. Check improper connections for high-voltage. Replace the higevoltage power supply.

• Code: 122
• Description: Low-voltage power supply FAN error. Low-voltage power supply temperature error.
• Troubleshooting Guides: Is the FAN (bottom right of the front) of the low voltage power supply block working? Is the FAN connector connected correctly? Check connections for connector of the FAN. Replace the lowvoltage power supply. Replace the FAN. Replace the lowvoltage power supply.

• Code: 123
• Description: Abnormal environment humidty /Not connected humidity sensor.
• Troubleshooting Guides: Does error reoccur? Yes Power Off/On. Replace the control panel board (PCQ board).

• Code: 124
• Description: Abnormal environment temperature.
• Troubleshooting Guides: Does error reoccur? Yes Power Off/On. Replace the control panel board (PCQ board).

• Code: 126
• Description: Condensation in the printer was detected.
• Troubleshooting Guides: Condensation iss likely to occur in printers carried from the outside. Turn on the printer again after it is exposed to room temperature for two hours to half a day. Does the error reoccur? Yes After leaving the printer at room temperature, turn on the power again. Replace the control panel board (PCQ board).

• Code: 127
• Description: Error detected at the fuser unit cooling FAN.
• Troubleshooting Guides: Is the FAN connector connected properly? Does error reoccur?
  Connect properly again. Replace the FAN motor. Replace the PU/ CU board

• Code: 128
• Description: Error detected at the engine FAN motors. 05: Fuser side FAN 08: REAR FAN 0B: ID FAN 2
• Troubleshooting Guides: Is the FAN connector connected properly? Does error reoccur?
  Connect properly again. Replace the FAN motor. Replace the PU/ CU board.

• Code: 134
• Description: LED head fault detected. (134=K)
• Troubleshooting Guides: Is LED head properly set? Does error reoccur?
  Set properly for LED head unit. Turn power ON agein. Replace LED head unit

• Code: 155
• Description: Fuser unit fuse cannot be disconnected.
• Troubleshooting Guides: Is fuser unit set properly? Does error reoccur?
  After cleaning for fuser connector, reset. Turn power ON again. Replace the PU/ CU board.

• Code: 163
• Description: Error detected by toner sensor. (163=K) This error does not occur with the factory default settings.
• Troubleshooting Guides: Is toner cartridge setting? Is toner lock lever setting? Does error reoccur?
  Set toner cartridge. Turn a lock lever of toner to a fixed position. Replace toner sensor or assembly.

• Code: 166
• Description: An abnormality was detected with the power supply temperature thermistor. 01: Short 02: Open 03: High temp. 04: Low temp.
• Troubleshooting Guides: 01, 02: Does error reoccur? Does error reoccur? Does error reoccur? 03: Does error reoccur? Does error reoccur? Does error reoccur? 04: Does error reoccur? Does error reoccur? Does error reoccur?
  Power Off/On. Replace the low voltage power supply unit. Replace the PU/ CU board. Replace the cable between the low voltage power supply unit and the PU/CU board. Remove anything obstructing the ventilation slots if any and restore the power. Replace the low voltage power supply unit. Replace the PU/ CU board. Replace the cable between the low voltage power supply unit and the PU/CU board. Raise the room temperature and restore the power. Replace the low voltage power supply unit. Replace the PU/ CU board. Replace the cable between the low voltage power supply unit and the PU/CU board.

• Code: 167
• Description: ThermistorSlope Error
• Troubleshooting Guides: Is the error message displayed? Does error reoccur?
  Power Off/On. After leaving the printer for 30 minutes, turn on the printer again.

• Code: 168
• Description: Compensation Thermistor Error
  01: Short 02: Open 03: High temp. 04: Low temp.
• Troubleshooting Guides: Is the error message displayed? Does error reoccur?
  Power Off/On. After leaving the printer for 30 minutes, turn on the printer again.

• Code: 169
• Description: Upper Side Thermistor Error 01: Short 02: Open 03: High temp. 04: Low temp.
• Troubleshooting Guides: Is the error message displayed? Does error reoccur?
  Power Off/On. After leaving the printer for 30 minutes, turn on the printer again.

• Code: 170, 171
• Description: Short circuit in fuser thermistor or open detected.
• Troubleshooting Guides: Does error reoccur? Yes Power Off/On. Replace the fuser unit.

• Code: 172, 173
• Description: Abnormal temperature detected by fuser thermistor (high-temp or low temp.)
• Troubleshooting Guides: Does error reoccur? Yes Power Off/On. Replace the fuser unit

• Code: 182, 184
• Description: Option unit I/F error
  182=Tray2 183=Tray3 184=Tray4
• Troubleshooting Guides: Does error reoccur? Yes Power Off/On. After checking connention parts of connector,replace option unit.

• Code: 190
• Description: System Memory Overflow.
• Troubleshooting Guides: Does error reoccur? Yes Power Off/On. Add option RAM DIMM.

• Code: 200, 202
• Description: PU Firmware download Error.(These problems are not occurred in the usual operating.)
• Troubleshooting Guides: Error occured while writing over the PU firmware. Turn the printer OFF/ON, and retry to download the PU firmware again.

• Code: 203, 204
• Description: An error was detected of the CU program. (These problems are not occurred in the usual operating.)
• Troubleshooting Guides: Reinstall the PU/CU board. Is the error message displayed again? After turn power OFF, check connections between CU board and PU board. Then turn power ON again.

• Code: 207, 208
• Description: An error was detected of the CU program. (These problems are not occurred in the usual operating.)
• Troubleshooting Guides: Reinstall the PU/CU board. Is the error message displayed again? After turn power OFF, check connections between CU board and PU board. Then turn power ON again.

• Code: 209
• Description: Media Table download Error. (This problem is not occurred in the usual operating.)
  Downloading Media Table to PU has failure. (Related to Custom Media Type)
• Troubleshooting Guides: Downloading Media Table to PU has failure. (Related to Custom Media Type) Turn the printer OFF/ON, and retry to download again.

• Code: 213, 214
• Description: An error was detected of the CU program. (These problems are not occurred in the usual operating.)
  Error occurred while printing
• Troubleshooting Guides: Error occurred while printing After turn power OFF, check connections between CU board and PU board. Then turn power ON again.

• Code: 231
• Description: Tag Interface Error
  05: K reader (TC/ID) – Tag interface connection error
  11: K reader (TC/ID) – Tag interface connection error
• Troubleshooting Guides: 05, 11: Does error reoccur? Does error reoccur after the power restoration? Is the Tag cable connected properly? Does error reoccur after the power restoration?
  Replace the toner cartridge, ID or Print Cartridge. Check the Tag cable. Connect the cable properly. Replace the PU/ CU board.

• Code: 250
• Description: Secure File Erasing Error
• Troubleshooting Guides: Did the user accept to execute Erase HDD? Inform the user that it is necessary to execute Disk ERASE to restore the HDD defaults in order to delete the encrypted file.

• Code: 251
• Description: Secure Disk Erasing Error
• Troubleshooting Guides: Error occurred during Disk ERASE. Does error reoccur? Power Off/On. Yes Replace the HDD.

• Code: 254
• Description: An unexcepted error occurred during initializing the security mode. Error cause information was displayed after an error number.
• Troubleshooting Guides: Does error reoccur? Yes Power Off/On. Regenerate an encryption key. If it doesn’t solve the problem, replace the PU/CU board or encrypted HDD.

• Code: 257
• Description: An unexcepted error occurred during initializing HDD. HDD Error cause information was displayed after an error number.
• Troubleshooting Guides: Does error reoccur? Yes Power Off/On. Format the HDD again. If it does not solve the problem, replace the HDD.

• Code: 901, 902
• Description: Short or open in Internal thermistor detected.
• Troubleshooting Guides: Is internal thermistor cable setting proper? Does error reoccur?
  Connect cable set properly again. Turn power ON again. Replace the internal thermistor.

• Code: 903, 904
• Description: Abnormal temperature detected by Internal thermistor (high-temp or low temp.)
• Troubleshooting Guides: Is internal thermistor cable setting proper? Does error reoccur?
  Connect cable set properly again. Turn power ON again. Replace the internal thermistor and leave aside for 30 minutes. Then turn power ON again.

• Code: 911, 912
• Description: The Geared Motor Error at the Optional Tray. 911:Tray2 912 Tray3
• Troubleshooting Guides: Is the indicated tray installed properly? Does error reoccur?
  Install the optional tray properly. Turn power ON again. Replace the Geared Motor of indicated tray.

• Code: 918
• Description: An error was detected with the Duplex Fan Motor.
• Troubleshooting Guides: Does error reoccur? Does error reoccur after power restoration?
  Power Off/On. Check if the FAN is connected properly. Replace the FAN.

• Code: 923
• Description: An error was detected with the image drum motor by overload.
• Troubleshooting Guides: Does error reoccur after power restoration? Does error reoccur after power restoration?
  Check if the image drum is installed properly. Replace the image drum unit. Replace the ID motor.

• Code: 928
• Description: An error was detected the Fuser Motor rotation by overload.
• Troubleshooting Guides: Does error reoccur after power restoration? Does error reoccur after power restoration?
  Check if the fuser is installed properly. Replace the fuser. Replace the fuser motor.

• Code: 933
• Description: Tray2 CPU Clock Frequency Error
• Troubleshooting Guides: Does error reoccur after power restoration? Does error reoccur after power restoration?
  Replace the unit. Replace the PU/ CU board.

• Code: 934
• Description: Tray3 CPU Clock Frequency Error
• Troubleshooting Guides: Does error reoccur after power restoration? Does error reoccur after power restoration?
  Replace the unit. Replace the PU/ CU board.

• Code: 935
• Description: Tray4 CPU Clock Frequency Error
• Troubleshooting Guides: Does error reoccur after power restoration? Does error reoccur after power restoration?
  Replace the unit. Replace the PU/ CU board.

• Code: 941
• Description: A watch dog timer error was detected.
• Troubleshooting Guides: Does error reoccur? Yes Power Off/On. Replace the PU/ CU board.

• Code: 942
• Description: An undefined interruption was detected.
• Troubleshooting Guides: Does error reoccur? Yes Power Off/On. Replace the PU/ CU board.

• Code: 943
• Description: PU CPU ran away out of control due to noise etc.
• Troubleshooting Guides: Does error reoccur? Yes Power Off/On. Replace the PU/ CU board.

• Code: 944
• Description: An error was detected with accessing the Dcon circuit.
• Troubleshooting Guides: Does error reoccur? Yes Power Off/On. Replace the PU/ CU board.

• Code: 945
• Description: SDRAM access at power on failed.
• Troubleshooting Guides: Does error reoccur? Yes Power Off/On. Replace the PU/ CU board.

• Code: 947
• Description: EMF Missing Error
• Troubleshooting Guides: Does error reoccur? Yes Power Off/On. Replace the PU/ CU board.

• Code: 948
• Description: Detect hopping motor rotate error
• Troubleshooting Guides: Error occurred when hopping motor error detected Power Off/On.

• Code: 982
• Description: Unsupport Tray Error
• Troubleshooting Guides: Are many trays beyond the specification installed? Yes Use trays as many as specified.

• Code: 984
• Description: Black Tag Version Mismatch
• Troubleshooting Guides: Does error reoccur? Yes Power Off/On. Replace the toner cartridge, the image drum or Print Cartridge.

• Code: 999
• Description: The PU/CU firmware has a problem with its compatibility.
• Troubleshooting Guides:

– Get more information about Epson XP 15000 troubleshooting, click here

– Get more error code list with quick guide to fix printer product, click here
– About get help with reseting Epson inkpad or others, click here

Waste Ink Pad Counter Utility Functions:

– Cleaning printhead.
– Ink charge.
– Fix Epson red lights blinking Error

– Fix Epson Service Required Error: A printer’s ink pad at the end of its service life Please contact Epson Support.

– Check the current value of waste ink counters and ink level counters.
– Clear Waste Ink Counters.
– Read and write serial number.
– Read and write USB ID.
– Read and write HEAD ID.
– Make EEPROM dump, backup.
– Paper feed test.
– Nozzle check.
– Color check pattern.
– Initialize (disable) PF deterioration offset.
– Retrieve device information

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