• Code: 6950
• Description: Fuser IH PWB communication error
  No response is received in 30 ms since a command is sent to IHCPU. A checksum error is detected 10 times in succession.
• Causes: Defective connector cable or poor contact in the connector.
  Defective fuser IH PWB.
  Defective engine PWB.
• Remedy: Defective connector cable or poor contact in the connector. Reinsert the connector. Also check for continuity within the connector cable. If none, replace the cable. Fuser IH PWB (YC4) and engine PWB (YC26)
  Defective fuser IH PWB. Replace the fuser IH PWB and check for correct operation.
  Defective engine PWB. Replace the engine PWB and check for correct operation.

• Code: 6990
• Description: Fuser power supply incompatibility Information won’t match between the engine backup and the fuser IH PWB.
• Causes: Defective fuser IH PWB.
  Defective engine PWB.
• Remedy: Defective fuser IH PWB. Replace the fuser IH PWB and check for correct operation.
  Defective engine PWB. Replace the engine PWB and check for correct operation.

• Code: 7001
• Description: Toner motor error
  During the toner motor is driven, an event in which a locking was detected for 5 times in 200 ms intervals has occurred in 30 sets.
• Causes: Defective connector cable or poor contact in the connector.
  Defective toner motor.
  Defective engine PWB.
• Remedy: Defective connector cable or poor contact in the connector. Reinsert the connector. Also check for continuity within the connector cable. If none, replace the cable. Toner motor and engine PWB (YC27)
  Defective toner motor. Replace the toner motor.
  Defective engine PWB. Replace the engine PWB and check for correct operation.

• Code: 7101
• Description: Toner sensor error
  Sensor output value of 60 or less or 944 or more continued for 3 s.
• Causes: Defective connector cable or poor contact in the connector.
  Defective toner sensor.
  Defective engine PWB.
• Remedy: Defective connector cable or poor contact in the connector. Reinsert the connector. Also check for continuity within the connector cable. If none, replace the cable. Toner sensor and front PWB (YC7) Front PWB (YC2) and engine PWB (YC8)
  Defective toner sensor. Replace developer unit.
  Defective engine PWB. Replace the engine PWB and check for correct operation.

• Code: 7200
• Description: Broken outer temperature sensor wire
  The sensor input sampling is greater than 230.
• Causes: Defective connector cable or poor contact in the connector.
  Defective outer temperature sensor.
  Defective engine PWB.
• Remedy: Defective connector cable or poor contact in the connector. Reinsert the connector. Also check for continuity within the connector cable. If none, replace the cable. Outer temperature sensor and front PWB (YC8) Front PWB (YC2) and engine PWB (YC8)
  Defective outer temperature sensor. Replace outer temperature sensor.
  Defective engine PWB. Replace the engine PWB and check for correct operation.

• Code: 7210
• Description: Short-circuited outer temperature sensor
  The sensor input sampling is less than 69.
• Causes: Defective connector cable or poor contact in the connector.
  Defective outer temperature sensor.
  Defective engine PWB.
• Remedy: Defective connector cable or poor contact in the connector. Reinsert the connector. Also check for continuity within the connector cable. If none, replace the cable. Outer temperature sensor 2 and front PWB (YC8) Front PWB (YC2) and engine PWB (YC8)
  Defective outer temperature sensor. Replace outer temperature sensor.
  Defective engine PWB. Replace the engine PWB and check for correct operation.

• Code: 7221
• Description: Broken LSU thermistor wire
  The sensor input sampling is greater than 230.
• Causes: Defective connector cable or poor contact in the connector.
  Defective LSU thermistor.
  Defective engine PWB.
• Remedy: Defective connector cable or poor contact in the connector. Reinsert the connector. Also check for continuity within the connector cable. If none, replace the cable. Laser scanner unit and LSU relay PWB (YC3) LSU relay PWB (YC2) and engine PWB (YC11)
  Defective LSU thermistor. Replace the laser scanner unit.
  Defective engine PWB. Replace the engine PWB and check for correct operation.

• Code: 7231
• Description: Short-circuited LSU thermistor
  The sensor input sampling is less than 69.
• Causes: Defective connector cable or poor contact in the connector.
  Defective LSU thermistor.
  Defective engine PWB.
• Remedy: Defective connector cable or poor contact in the connector. Reinsert the connector. Also check for continuity within the connector cable. If none, replace the cable. Laser scanner unit and LSU relay PWB (YC3) LSU relay PWB (YC2) and engine PWB (YC11)
  Defective LSU thermistor. Replace the laser scanner unit.
  Defective engine PWB. Replace the engine PWB and check for correct operation.