Post-Belt Sensor paper jam error

Error code
  • 78 Post-Belt Sensor paper jam error
Occurrence condition
  • The Post-Belt Sensor detected paper when the power was turned ON, when the cover was closed, when the product recovered from the power saving mode, or when the printing operation ended
Assumed cause
  • Foreign objects or pieces of paper in the paper transport path
  • Post-Belt Sensor has a dirty surface, has fallen off, or is faulty
  • MCU board failure
Related parts
  • Post-Belt Sensor
  • Post-Belt Guide Unit
Troubleshooting
Step Confirmation and action YES NO
1

Check paper transport path

Is there any foreign matter, paper chips, etc. in the paper transport path?

Remove foreign matter, paper fragments, etc.

Go to step 2

2

Check the operation of the Post-Belt Sensor

Check the operation of the Post-Belt Sensor with the diagnostic function.

Judgment: Does the signal change between when the paper is placed and when it is not?

End Go to step 3
3

Check the Post-Belt Sensor for installation, dirt, and connector connection

Is the Post-Belt Sensor installed improperly? Is there dirt on the sensor? Is the connector not fully inserted?

Is the relay connector on the Rear Frame side not fully inserted?

Clean the sensor surface, or fully insert the connector.

Replace the parts one by one.

  • Post-Belt Sensor
  • Post-Belt Guide Unit
  • MCU Board