• Code: C6230
• Description: Fuser thermistor 1 edge break error Fuser thermistor 1 detects a temperature of 40C/104F or lower for 30 s.
• Causes: Defective fuser heater 1.
  Installation defectiveness on fuser thermistor 1.
  Defective PWB.
• Remedy: Defective fuser heater 1. Check for continuity across each heater. If none, replace the fuser unit.
  Installation defectiveness on fuser thermistor 1. Measure the resistance. If it is ∞, replace the fuser unit.
  Defective PWB. Replace the power source PWB or engine PWB and check for correct operation.

• Code: C6400
• Description: Zero-cross signal error
  While fuser heater ON/OFF control is performed, the zero-cross signal is not input within 3 s.
• Causes: Poor contact in the connector terminals.
  Defective PWB.
• Remedy: Poor contact in the connector terminals. Check the connection of connector YC4 on the engine PWB and the connector YC10 on the power souce PWB, and the continuity across the connector terminals. Repair or replace if necessary.
  Defective PWB. Replace the engine PWB or power source PWB and check for correct operation.

• Code: C6410
• Description: Fuser unit type mismatch problem
  Absence of the fuser unit is detected.
• Causes: Fuser unit connector inserted incorrectly.
  Different type of the fuser unit is installed.
• Remedy: Fuser unit connector inserted incorrectly. Reinsert the fuser unit connector if necessary.
  Different type of the fuser unit is installed. Install the correct fuser unit.

• Code: C7000
• Description: Toner motor problem
  After driving of the toner motor starts, the error signal is not at the H level for 500 ms continuously.
• Causes: Poor contact in the connector terminals.
  Broken the gear
  Defective toner motor M/C/Y/K.
  Defective engine PWB.
• Remedy: Poor contact in the connector terminals. Check the connection of connector YC26 on the engine PWB and the connector of the toner motor, and the continuity across the connector terminals. Repair or replace if necessary.
  Broken the gear. Check visually and replace the gear if necessary.
  Defective toner motor M/C/Y/K. Run maintenance item U135 and check if the toner motor operates. If not, replace the toner motor.
  Defective engine PWB. Replace the engine PWB and check for correct operation.

• Code: C7100
• Description: Toner container motor error
  The rated speed achievement signal does not turn to L within 2 s since toner container motor is activated. The rated speed achievement signal is at the H level for 1 s continuously after toner container motor is stabilized.
• Causes: Poor contact in the connector terminals.
  Defective drive transmission system.
  Defective toner container motor
  Defective engine PWB.
• Remedy: Poor contact in the connector terminals. Check the connection of connector YC26 on the engine PWB and the connector on the toner container motor, and the continuity across the connector terminals. Repair or replace if necessary.
  Defective drive transmission system. Check if the rollers and gears rotate smoothly. If not, grease the bushings and gears. Check for broken gears and replace if any.
  Defective toner container motor. Run maintenance item U030 and check if the toner container motor operates when YC26-A7 (remote signal) on the engine PWB goes low. If not, replace the toner container motor.
  Defective engine PWB. Run maintenance item U030 and check if YC26-A7 (remote signal) on the engine PWB goes low. If not, replace the engine PWB.

• Code: C7101
• Description: Toner sensor K problem
  Sensor output value of 60 or less or 944 or more continued for 3 s.
• Causes: Defective developing unit K.
  Defective PWB.
• Remedy: Defective developing unit K. Replace the developing unit K.
  Defective PWB. Replace the main front PWB or engine PWB and check for correct operation.

• Code: C7102
• Description: Toner sensor C problem Sensor output value of 60 or less or 944 or more continued for 3 s.
• Causes: Defective developing unit C.
  Defective PWB.
• Remedy: Defective developing unit C. Replace the developing unit C.
  Defective PWB. Replace the sub front PWB or engine PWB and check for correct operation.

• Code: C7103
• Description: Toner sensor M problem Sensor output value of 60 or less or 944 or more continued for 3 s.
• Causes: Defective developing unit M.
  Defective PWB.
• Remedy: Defective developing unit M. Replace the developing unit M.
  Defective PWB. Replace the sub front PWB or engine PWB and check for correct operation.