• Code: 0300
• Description: Polygon motor malfunction • The polygon motor does not rotate evenly even after the lapse of a given period of time after it has been started. • The motor lock signal remains HIGH for a given period of consecutive time while the polygon motor is being rotated.
• Causes: • PH unit • Printer control board (PRCB)
• Remedy: 1 Check the connector between PH unit-relay CN63- PRCB CN18 for proper connection and correct as necessary. 2 Replace the PH unit. 3 Replace PRCB.

• Code: 0310
• Description: Laser malfunction The SOS signal is not detected within a given period of time after the output of the laser has been started.
• Causes: • PH unit • Printer control board (PRCB) • MFP board (MFPB)
• Remedy: 1 Check the connector between PH unit-relay CN63- PRCB CN18 for proper connection and correct as necessary. 2 Check the connector between PH unit-MFPB CN15 for proper connection and correct as necessary. 3 Replace the PH unit. 4 Replace PRCB.

• Code: 0315
• Description: PH board communication error • Mismatching of data being written and read occurs continuously for certain times during communication with the PH board. • The EEPROM of the PH board is not yet initialized.
• Causes: • Front door sensor (PS10) • Right door sensor (PS11) • Front door switch (SW2) • Right door switch (SW3) • DC power supply (DCPU) • Printer control board (PRCB) • MFP board (MFPB) • PH unit
• Remedy: 1 Check the connector between PRCB CN18-relay CN63-PH unit for proper connection and correct as necessary. 2 Replace the PH unit. 3 Replace PRCB.

• Code: 0500
• Description: Heating roller warm-up failure The thermistor/1 does not detect the specified temperature and the warm-up cycle is not completed even after the lapse of a given period of time after the cycle has been started.
• Causes: • Fusing unit • Printer control board (PRCB) • DC power supply (DCPU)
• Remedy: 1 Check the fusing unit for correct installation (whether it is secured in position). 2 Check the connector between fusing unit-PRCB CN9 for proper connection and correct as necessary. 3 Check the connector between fusing unit-DCPU CN2 for proper connection and correct as necessary. 4 Replace the fusing unit. 5 Replace PRCB. 6 Replace DCPU.

• Code: 0502
• Description: Thermistor open-circuit failure The temperature detected by the thermistor/1 or thermistor/2 does not reach a predetermined level even after the lapse of a given period time after the warm-up cycle has been started.
• Causes: • Fusing unit • Printer control board (PRCB) • DC power supply (DCPU)
• Remedy: 1 Check the fusing unit for correct installation (whether it is secured in position). 2 Check the connector between fusing unit-PRCB CN9 for proper connection and correct as necessary. 3 Check the connector between fusing unit-DCPU CN2 for proper connection and correct as necessary. 4 Replace the fusing unit. 5 Replace PRCB. 6 Replace DCPU.

• Code: 0503
• Description: Thermistor resistance failure The difference between the temperature detected by thermistor/1 and that detected by thermistor/2 exceeds a predetermined value.
• Causes: • Fusing unit • Printer control board (PRCB) • DC power supply (DCPU)
• Remedy: 1 Check the fusing unit for correct installation (whether it is secured in position). 2 Check the connector between fusing unit-PRCB CN9 for proper connection and correct as necessary. 3 Check the connector between fusing unit-DCPU CN2 for proper connection and correct as necessary. 4 Replace the fusing unit. 5 Replace PRCB. 6 Replace DCPU.

• Code: 0510
• Description: Abnormally low heating roller temperature The temperature detected by the thermistor/1 or thermistor/2 remains lower than the specified value.
• Causes: • Fusing unit • Printer control board (PRCB) • DC power supply (DCPU)
• Remedy: 1 Check the fusing unit for correct installation (whether it is secured in position). 2 Check the connector between fusing unit-PRCB CN9 for proper connection and correct as necessary. 3 Check the connector between fusing unit-DCPU CN2 for proper connection and correct as necessary. 4 Replace the fusing unit. 5 Replace PRCB. 6 Replace DCPU.

• Code: 0520
• Description: Abnormally high heating roller temperature The temperature detected by the thermistor/1 or thermistor/2 remains higher than the specified value.
• Causes: • Fusing unit • Printer control board (PRCB) • DC power supply (DCPU)
• Remedy: 1 Check the fusing unit for correct installation (whether it is secured in position). 2 Check the connector between fusing unit-PRCB CN9 for proper connection and correct as necessary. 3 Check the connector between fusing unit-DCPU CN2 for proper connection and correct as necessary. 4 Replace the fusing unit. 5 Replace PRCB. 6 Replace DCPU.