Paper tray is full but display still reads to load paper. There is a small sensor? dohickie hanging down inside. It was loose. I reconnected it but am not sure how it fits inside the machine. Pushing in paper tray just knocks it looses again so I am sure it isnt supposed to be hanging down.

Printers have a paper out sensor and corresponding flag that hangs down under the printer when the paper tray is removed or opened. From your description there is some issue with this flag and/or sensor which is registering the paper out signal when in fact paper is loaded into the tray and the tray is installed.

Hope this helped.

Tony
www.aimdistribution.com

First, when you put the paper in the tray make sure the paper holders on the side and back of the tray are positioned against the paper stack but not so much as to be snug.
Next, inside the compartment where the paper try is inserted look for a small plastic piece that hangs below the ceiling of the compartment. It should be near the front of the compartment hanging down and should swing freely backward.
Also, in the printer's paper tray settings make sure that tray is set to that size of paper you are using.

Hello!
You already found the problem. That sensor is the paper sensor. It probably is broken. You need to replace it or glu it.

There is a sensor above the tray where the paper comes out, and that sensor has a long black actuator. Sometimes that actuator gets turned to the side, and this will cause that message to appear.

Reach above the rollers where the paper exits the copier, find the black actuator, and turn it so that it is hanging down over the tray. Once the sensor is reset that message should disappear.

When it says that it usually means there is a paper scrap in the sensor flag that is under the long gray roller. It is a black plastic tab toward the right side behind the white plastic guides that the paper comes out under. You need a flashlight to see it and you need to be careful not to break the tab.

First check the machine for paper jams. If not, remove the paper from the paper tray and reinstall it. Then try to print from the MP tray.If this works, check paper size settings on the printer driver, or the small black arm which hangs down next to the paper pick up roller, and is the paper sensor.

There should be a plastic flag that hangs down into the tray. When the tray is full the other end of the flag moves out of the path of an inferred sensor. Locate the sensor and try cleaning it.

1-are the guides set correctly?
2-is the sensor flag there? on the bottomof the machine when you take out the tray you should see a piece of plastic hanging and is very loose it is the sensor for the paper, ( although I have seen it work without it !!!!!!)

Your paper sensor actuator arm is most likely broken or out of position, or you may have a dirty sensor if you are in a dusty environment. If you look in the machine with the tray out, you should see a small (usually black) piece of plastic hanging down. You can also take the toner and drum cartridge out and turn it on its back to get a better look. If it's not there, it's probably broken off.

There is a black, curved-shape piece that hangs down (protrudes) from within the paper bay (visible with cartridge removed) that is spring-loaded. That piece might be jammed or broken.