• Code: 5102
• Description: Main high-voltage error C Measure the inflowing current when Vpp is varied in 3 steps and verify if the difference of the currents of 0 and step 2 is less than 42 (51 if lower highvoltage board).
• Remedy: Drum unit 1. Execute U030 Belt Mean Drum Motor and check that the drum motor can rotate. 2. Confirm that the drum or the drum screw can rotate. 3. Check that the discharger lamp is properly connected. 4. If it won’t rotate, replace the drum unit.
  Charger roller unit 1. Check that the high-voltage contacts are not distorted or adhered with foreign objects. 2. Reinstall the chrager roller unit.Or, replace the charger roller unit.
  High voltage PWB 1 1. Confirm that the wiring connector is firmly connected and, if necessary, connect the connector all the way in. High voltage PWB 1(YC2) and Engine PWB (YC16) 2. If the wiring is disconnected, shorted or grounded, replace the wiring. 3. Replace the High voltage PWB 1.
  Engine PWB 1. Check the engine software and upgrade to the latest, if necessary. 2. Replace the engine PWB.

• Code: 5103
• Description: Main high-voltage error M Measure the inflowing current when Vpp is varied in 3 steps and verify if the difference of the currents of 0 and step 2 is less than 42 (51 if lower highvoltage board).
• Remedy: Drum unit 1. Execute U030 Belt Mean Drum Motor and check that the drum motor can rotate. 2. Confirm that the drum or the drum screw can rotate. 3. Check that the discharger lamp is properly connected. 4. If it won’t rotate, replace the drum unit.
  Charger roller unit 1. Check that the high-voltage contacts are not distorted or adhered with foreign objects. 2. Reinstall the chrager roller unit.Or, replace the charger roller unit.
  High voltage PWB 1 1. Confirm that the wiring connector is firmly connected and, if necessary, connect the connector all the way in. High voltage PWB 1(YC3) and Engine PWB (YC17) 2. If the wiring is disconnected, shorted or grounded, replace the wiring. 3. Replace the High voltage PWB 1.
  Engine PWB 1. Check the engine software and upgrade to the latest, if necessary. 2. Replace the engine PWB.

• Code: 5104
• Description: Main high-voltage error Y Measure the inflowing current when Vpp is varied in 3 steps and verify if the difference of the currents of 0 and step 2 is less than 42 (51 if lower highvoltage board).
• Remedy: Drum unit 1. Execute U030 Belt Mean Drum Motor and check that the drum motor can rotate. 2. Confirm that the drum or the drum screw can rotate. 3. Check that the discharger lamp is properly connected. 4. If it won’t rotate, replace the drum unit.
  Charger roller unit 1. Check that the high-voltage contacts are not distorted or adhered with foreign objects. 2. Reinstall the chrager roller unit.Or, replace the charger roller unit.
  High voltage PWB 1 1. Confirm that the wiring connector is firmly connected and, if necessary, connect the connector all the way in. High voltage PWB 1(YC1) and Engine PWB (YC16) 2. If the wiring is disconnected, shorted or grounded, replace the wiring. 3. Replace the High voltage PWB 1.
  Engine PWB 1. Check the engine software and upgrade to the latest, if necessary. 2. Replace the engine PWB.

• Code: 6000
• Description: Broken fuser heater wire Fuser center thermistor 1 does not reach 100° C/ 212 °F even after 60 s during warming up. The detected temperature of fuser center thermistor 1 does not reach the specified temperature (ready indication temperature) for 420 s in warming up after reached to 100° C/ 212 °F.
• Remedy: Fuser unit 1. Check that no paper jam is present. 2. Confirm that the wiring connector is firmly connected and, if necessary, connect the connector all the way in. Fuser unit and Engine PWB (YC26) 3. If the wiring is disconnected, shorted or grounded, replace the wiring. 4. Replace the Fuser unit and execute U167 counter clear. (Deteriorated sensitivity due to the toner adhered to the center thermistor.)
  Engine PWB 1. Check the engine software and upgrade to the latest, if necessary. 2. Replace the engine PWB.
  Fuser IH PWB 1. Confirm that the wiring connector is firmly connected and, if necessary, connect the connector all the way in. Fuser IH PWB(YC4) and Engine PWB (YC26) 2. Replace the fuser IH PWB.
  Fuser IH unit 1. Confirm that the wiring connector is firmly connected and, if necessary, connect the connector all the way in. Fuser IH unit and Fuser IH PWB (YC9 and 10) 2. If the wiring is disconnected, shorted or grounded, replace the wiring. 3. Replace the fuser IH unit.

• Code: 6020
• Description: Abnormally high fuser Center thermistor 1 temperature Fuser center thermistor 1 detects a temperature higher than 240°C/ 464°F for 1 s.
• Remedy: Fuser unit 1. Confirm that the wiring connector is firmly connected and, if necessary, connect the connector all the way in. Fuser unit and Engine PWB (YC26) 2. If the wiring is disconnected, shorted or grounded, replace the wiring. 3. Replace the Fuser unit.
  Engine PWB 1. Check the engine software and upgrade to the latest, if necessary. 2. Replace the engine PWB.

• Code: 6030
• Description: Broken fuser center thermistor 1 wire Input from fuser center thermistor 1 is 1010 or more (A/D value) continuously for 1 s. Verify if A/D read in the differential output won’t change by 4 or more when it was turned on for 10 seconds in a lowtemperature environment.
• Remedy: Fuser unit 1. Check that no paper jam is present. 2. Confirm that the wiring connector is firmly connected and, if necessary, connect the connector all the way in. Fuser unit and Engine PWB (YC26) 3. If the wiring is disconnected, shorted or grounded, replace the wiring. 4. Replace the Fuser unit and execute U167 counter clear. (Deteriorated sensitivity due to the toner adhered to the center thermistor.)
  Engine PWB 1. Check the engine software and upgrade to the latest, if necessary. 2. Replace the engine PWB.
  Fuser IH PWB 1. Confirm that the wiring connector is firmly connected and, if necessary, connect the connector all the way in. Fuser IH PWB(YC4) and Engine PWB (YC26) 2. Replace the Fuser IH PWB.
  Fuser IH unit 1. Confirm that the wiring connector is firmly connected and, if necessary, connect the connector all the way in. Fuser IH unit and Fuser IH PWB (YC9 and 10) 2. If the wiring is disconnected, shorted or grounded, replace the wiring. 3. Replace the fuser IH unit.

• Code: 6040
• Description: Fuser heater error Input from fuser center thermistor 1 is abnormal value continuously for 1 s.
• Remedy: Fuser unit 1. Confirm that the wiring connector is firmly connected and, if necessary, connect the connector all the way in. Fuser unit and Engine PWB (YC26) 2. If the wiring is disconnected, shorted or grounded, replace the wiring. 3. Replace the Fuser unit and execute U167 counter clear.
  Engine PWB 1. Check the engine software and upgrade to the latest, if necessary. 2. Replace the engine PWB.
  Fuser IH PWB 1. Confirm that the wiring connector is firmly connected and, if necessary, connect the connector all the way in. Fuser IH PWB (YC4) and Engine PWB (YC26) 2. Replace the fuser IH PWB.

• Code: 6050
• Description: Abnormally low fuser center thermistor 1 temperature Fuser center thermistor 1 detects a temperature lower than 100°C/ 212°F for 1 s after warming up, during ready or during print.
• Remedy: Power source 1. Check that the operating voltage falls within +/-10%. 2. Check no voltage drop is caused. The heater is deactivated at 70V or lower. 3. Relocate the AC outlet that supplies power.
  Fuser unit 1. Confirm that the wiring connector is firmly connected and, if necessary, connect the connector all the way in. Fuser unit and Engine PWB (YC26) 2. If the wiring is disconnected, shorted or grounded, replace the wiring. 3. Replace the Fuser unit and execute U167 counter clear.
  Engine PWB 1. Check the engine software and upgrade to the latest, if necessary. 2. Replace the engine PWB.
  Fuser IH PWB 1. Confirm that the wiring connector is firmly connected and, if necessary, connect the connector all the way in. Fuser IH PWB(YC4) and Engine PWB (YC26) 2. Replace the Fuser IH PWB.
  Fuser IH unit 1. Confirm that the wiring connector is firmly connected and, if necessary, connect the connector all the way in. Fuser IH unit and Fuser IH PWB (YC9 and 10) Fuser IH PWB( YC4) and Engine PWB (YC26) 2. If the wiring is disconnected, shorted or grounded, replace the wiring. 3. Replace the fuser IH unit.