• Code: 7242
• Description: Broken developer thermistor C wire The sensor input sampling is greater than 230.
• Remedy: Developer thermistor C 1. Confirm Developing is displayed by U139 temperature and humidity. 2. Confirm that the wiring connector is firmly connected and, if necessary, connect the connector all the way in. Developer unit C and Front PWB (YC13) Front PWB (YC2) and Engine PWB (YC10) 3. If the wiring is disconnected, shorted or grounded, replace the wiring. 4. Replace the Developer unit C.
  Front PWB Replace the front PWB
  Engine PWB 1. Check the engine software and upgrade to the latest, if necessary. 2. Replace the engine PWB.

• Code: 7243
• Description: Broken developer thermistor M wire The sensor input sampling is greater than 230.
• Remedy: Developer thermistor M 1. Confirm Developing is displayed by U139 temperature and humidity. 2. Confirm that the wiring connector is firmly connected and, if necessary, connect the connector all the way in. Developer unit M and Front PWB (YC11) Front PWB (YC2) and Engine PWB (YC10) 3. If the wiring is disconnected, shorted or grounded, replace the wiring. 4. Replace the Developer unit M.
  Front PWB Replace the front PWB
  Engine PWB 1. Check the engine software and upgrade to the latest, if necessary. 2. Replace the engine PWB.

• Code: 7244
• Description: Broken developer thermistor Y wire The sensor input sampling is greater than 230.
• Remedy: Developer thermistor Y 1. Confirm Developing is displayed by U139 temperature and humidity. 2. Confirm that the wiring connector is firmly connected and, if necessary, connect the connector all the way in. Developer unit Y and Front PWB (YC15) Front PWB (YC2) and Engine PWB (YC10) 3. If the wiring is disconnected, shorted or grounded, replace the wiring. 4. Replace the Developer unit Y.
  Front PWB Replace the front PWB
  Engine PWB 1. Check the engine software and upgrade to the latest, if necessary. 2. Replace the engine PWB.

• Code: 7251
• Description: Short-circuited developer thermistor K The sensor input sampling is less than 69.
• Remedy: Developer thermistor K 1. Confirm Developing is displayed by U139 temperature and humidity. 2. Confirm that the wiring connector is firmly connected and, if necessary, connect the connector all the way in. Developer unit K and Front PWB (YC9) Front PWB (YC2) and Engine PWB (YC10) 3. If the wiring is disconnected, shorted or grounded, replace the wiring. 4. Replace the Developer unit K.
  Front PWB Replace the front PWB
  Engine PWB 1. Check the engine software and upgrade to the latest, if necessary. 2. Replace the engine PWB.

• Code: 7252
• Description: Short-circuited developer thermistor C The sensor input sampling is less than 69.
• Remedy: Developer thermistor C 1. Confirm Developing is displayed by U139 temperature and humidity. 2. Confirm that the wiring connector is firmly connected and, if necessary, connect the connector all the way in. Developer unit C and Front PWB (YC13) Front PWB (YC2) and Engine PWB (YC10) 3. If the wiring is disconnected, shorted or grounded, replace the wiring. 4. Replace the Developer unit C.
  Front PWB Replace the front PWB
  Engine PWB 1. Check the engine software and upgrade to the latest, if necessary. 2. Replace the engine PWB.

• Code: 7253
• Description: Short-circuited developer thermistor M The sensor input sampling is less than 69.
• Remedy: Developer thermistor M 1. Confirm Developing is displayed by U139 temperature and humidity. 2. Confirm that the wiring connector is firmly connected and, if necessary, connect the connector all the way in. Developer unit M and Front PWB (YC11) Front PWB (YC2) and Engine PWB (YC10) 3. If the wiring is disconnected, shorted or grounded, replace the wiring. 4. Replace the Developer unit M.
  Front PWB Replace the front PWB
  Engine PWB 1. Check the engine software and upgrade to the latest, if necessary. 2. Replace the engine PWB.

• Code: 7254
• Description: Short-circuited developer thermistor Y wire The sensor input sampling is less than 69.
• Remedy: Developer thermistor Y 1. Confirm Developing is displayed by U139 temperature and humidity. 2. Confirm that the wiring connector is firmly connected and, if necessary, connect the connector all the way in. Developer unit Y and Front PWB (YC15) Front PWB (YC2) and Engine PWB (YC10) 3. If the wiring is disconnected, shorted or grounded, replace the wiring. 4. Replace the Developer unit Y.
  Front PWB Replace the front PWB
  Engine PWB 1. Check the engine software and upgrade to the latest, if necessary. 2. Replace the engine PWB.

• Code: 7301
• Description: Toner hopper motor K error During the Toner hopper motor K is driven, an event in which a locking was detected for 15 times in 200 ms intervals.
• Remedy: Toner hopper motor K 1. Check the drive gear can rotate or they are not unusually loaded and, if necessary, replace. 2. Confirm that the wiring connector is firmly connected and, if necessary, connect the connector all the way in. Toner hopper motor K and retainer PWB (YC4) Retainer PWB (YC3) and front PWB (YC6) Front PWB (YC3) and engine PWB (YC7) 3. If the wiring is disconnected, shorted or grounded, replace the wiring. 4. Replace the Toner motor K.
  Screw sensor K 1. Check that the sensor is correctly positioned. 2. Confirm that the wiring connector is firmly connected and, if necessary, connect the connector all the way in. Screw sensor K and Engine PWB (YC27) 3. Replace the screw sensor K.
  Engine PWB 1. Check the engine software and upgrade to the latest, if necessary. 2. Replace the engine PWB.