M775 Upper bin full error

[Savills_Belux]

Hello,

The M775 likes to print a few page, and then will say the upper bin is full. This has never happened before and it's driving me crazy because I have a lot of stapled copies to print.

Does anyone know how I can fix it?

Thank you

[Repairatrooper]

Are you getting a specific error code when this happens? The paper path on this device is fairly complex and has many sensors and an error code can help point towards the culprit. 

[Savills_Belux]

Hi Repairtrooper,

There is no code, the screen simply says "Upper bin full" once paper has successfully completed the circuit and is dropped into the bin.

I have taken a direct look at the printing process myself. The printer starts printing, the paper is fed correctly and exits through the correct opening. The error appears as soon as the paper falls down and pushes a black mechanical plastic part down. 

Here are the photos of the aforementioned black mechanical part :

Tiny mechanical trigger that triggers error on screen.Tiny mechanical trigger that triggers error on screen.

Here's a link to an Imgur album containing a video of the printing process : https://imgur.com/a/sIf8a7m

[Repairatrooper]

You likely have a sensor error, but not that one on the tray. Your will need to go into the troubleshooting menu and check the manual sensor test to see if a sensor is always tripped. Do you get the error regardless of the output you have selected? If yes check the output sensor for the standard output bin as there is where that sensor is located.