1. There is a problem with the scanner, mirror and transfer assembly

Check the scanner, reflector and transfer components, and repair or replace them in time.

2. The protective cover is not opened, and the conductive steel sheet of the magnetic roller is not in contact with the conductive metal wire of the machine

At this time, you need to take out the powder box and reinstall the machine. Make sure that the protective cover is completely hit and the conductive steel sheet of the magnetic roller is in good contact with the conductive metal wire of the machine.

3. The photosensitive drum gear is loose

If the photosensitive drum gear is loose, tighten it carefully.