• Code: C200
• Description: Drive motor problem
  • LOCK ALM signal remains high for 1 s, 1 s after the drive motor has turned on.
• Causes: Poor contact of the drive motor connector terminals. Defective drive motor rotation control circuit. Defective drive transmission system.
• Remedy: Reinsert the connector. Also check for continuity within the connector cable. If none, repair or replace the cable. Replace the drive motor. Check if the rollers and gears rotate smoothly. If not, grease the bushings and gears. Check for broken gears and replace if any.

• Code: C310
• Description: Scanner carriage problem
  • The home position is not correct when the power is turned on or at the start of copying using the contact glass.
• Causes: Poor contact of the connector terminals. Defective scanner home position switch. Defective main PCB. Defective scanner motor.
• Remedy: Check the connection of connectors CN28 and CN25 on the main PCB and the continuity across the connector terminals. Remedy or replace if necessary. Replace the scanner home position switch. Replace the main PCB and check for correct operation. Replace the scanner motor.

• Code: C400
• Description: Polygon motor synchronization problem
  • The polygon motor does not reach a stable speed within 19 s of the polygon motor remote signal turning on.
• Causes: Poor contact of the polygon motor connector terminals.
• Remedy: Reinsert the connector. Also check for continuity within the connector cable. If none, repair or replace the cable.

• Code: C401
• Description: Polygon motor steady-state problem
  • The polygon motor rotation is not stable for 400 ms after the polygon motor rotation has been stabilized.
• Causes: Poor contact of the polygon motor connector terminals. Defective power source PCB.
• Remedy: Reinsert the connector. Also check for continuity within the connector cable. If none, repair or replace the cable. Check if 24 V DC is present at CN3-1 and CN3-2 on the power source PCB. If not, replace the power source PCB.

• Code: C420
• Description: BD steady-state problem
  • The VTC detects a BD error for 800 ms after the polygon motor rotation has been stabilizad.
• Causes: Poor contact of the laser scanner unit connector terminals. Defective LSU. Defective main PCB.
• Remedy: Reinsert the connector. Also check for continuity within the connector cable. If none, repair or replace the cable. Replace the LSU. Replace the main PCB and check for correct operation.

• Code: C510
• Description: Main charger problem
  • MC ALM signal is detected continuously for 800 ms when MC REM signal is turned on.
• Causes: Poor contact of the high-voltage transformer PCB connector terminals. Defective high-voltage transformer PCB. Leakage during main charging. Deformed high-voltage transformer PCB terminal spring.
• Remedy: Reinsert the connector. Also check for continuity within the connector cable. If none, repair or replace the cable. Replace the high-voltage transformer PCB. Check and clean the main charger assembly. Replace the spring.

• Code: C610
• Description: Broken fixing heater wire
  • Warm-up does not end within 90 s.
  • The secondary stabilization fixing temperature drops to 100°C/212°F or below.
  • The fixing temperature remains below 40˚C/104˚F for 7 s or longer after the fixing heaters have been turned on.
• Causes: Fixing heater installed incorrectly. Broken fixing heater wire. Poor contact in the fixing unit thermistor connector terminals. Broken fixing unit thermistor wire. Fixing unit thermistor installed incorrectly. Fixing unit thermostat triggered.
• Remedy: Check and reinstall if necessary. Check for continuity. If none, replace fixing heater. Check the connection of connector CN12 on the main PCB and the continuity across the connector terminals. Remedy or replace if necessary. Measure the resistance. If it is ∞Ω, replace the fixing unit thermistor. Check and reinstall if necessary. Check for continuity. If none, replace the fixing unit thermostat. Check the operation of the cooling fan and repair if necessary.

• Code: C620
• Description: Abnormally low fixing unit thermistor temperature
  • The fixing temperature remains below 100˚C/212˚F for 10 s during copying.
• Causes: Fixing heater installed incorrectly. Broken fixing heater wire. Poor contact in the fixing unit thermistor connector terminals. Broken fixing unit thermistor wire. Fixing unit thermistor installed incorrectly.
• Remedy: Check and reinstall if necessary. Check for continuity. If none, replace fixing heater. Check the connection of connector CN12 on the main PCB and the continuity across the connector terminals. Remedy or replace if necessary. Measure the resistance. If it is ∞Ω, replace the fixing unit thermistor. Check and reinstall if necessary. Check for continuity. If none, replace the fixing unit thermostat. Check the operation of the cooling fan and repair if necessary.