OKI MB780MFP

Before starting, check the media route for foreign objects, such as staples, clips, and scraps, in the media path.

Step	Check	Yes	No
1	Check the media condition. Load new, dry, recommended media, and perform a print test. Is the image density normal?	Problem solved.	Go to step 2.
2	Check the toner level. Is the toner level normal?	Go to step 3.	Replace the print cartridge.
3	Check the transfer roll assembly for contamination and wear. Is the above component free of excess wear and contamination?	Go to step 4.	Replace the transfer roll assembly.
4	Check the print cartridge for proper installation. Is the print cartridge properly installed?	Go to step 5.	Inspect, clean and reinstall replace the print cartridge.
5	Check the laser beam route. Check for debris between the printhead assembly and the PC drum. Is the laser beam route free of debris and the glass window, in the printhead assembly, free of contamination?	Go to step 6.	Remove debris or clean the printhead assembly window.
6	Check the HVPS card assembly for proper connection. Is the above component properly connected?	Replace the HVPS card assembly.	Replace the connections.
7	Check the printhead assembly for proper connection. Is the above component properly connected?	Replace the printhead assembly.	Replace the connections.
8	Perform a print test. Does the problem remain?	Contact next highest level of tech support.	Problem solved.