Why does my Dell MFP 3115cn Laser printer keep giving a paper jam message when there is no paper jam?

SOURCE: Dell 1600 paper jam 1 or no cartridge

Your unit is actually manufactured by Samsung. Most probably you have a bad paper sensor. As a technician, you will find these sensors on the power supply board (SMPS)or main board. If your are receiving tech support from Dell, please illustrate those guys on how to do their job.

SOURCE: Dell Laser MFP 1815 won't print. Message keeps

I had same problem. If you go to rear of printer and open the back door you'll see it is attached to a blue connector. Unattached it so that the door opens fully and then unflap the inside roller assembly. Next open the fuser door and you'll notice a little spring loaded assembly on the inside of the opened fuser door. This is where my problem was. Make sure that the assembly springs back when pushed because part communicates with a sensor on the motherboard. If it doesn't spring back then the printer thinks there is a jam. Mine was stuck but after pushing it a few times it started to work freely again. This was a frustrating problem but that fixed my issue and hopefully it will fix yours.

SOURCE: who can fix my printer from paper jamming?

If you mean that the print cycle starts, but the "Paper Jam" lights up at the point where the paper starts to enter the drum, here's what I found worked.

The rollers that feed the paper come down onto the clean sheets on a plastic, spring-loaded arm Those rollers sometimes get too slick after a lot of use and they won't push the paper up and into the drum -- they slip like worn tires.

Solution: slip the rubber "tires"off the plastic roller "wheels" and reverse them, inside-out. Put them back on the wheels and the new rubber surface will probably push the paper just fine.

To do this you have to turn the machine upside down and remove the paper tray. I would unplug the unit and remove the drum as well before trying this.

Good luck.

SOURCE: dell laser mfp 1815 dn "scanner locked" message

When you lift the scanner lid look to the left bottom. you should see a green slider button. If you stick your hand in the output tray and get it rigth under the green slider you will find a lever. Move that thing backwards or forwards, that is your unlocker.

SOURCE: MFP 1815 D Unlock Scanner message

Inside the print tray (where the paper comes out) on the upper right there is a blue lever. Pull it toward you and that will unlock the scanner. I just did this and restarted my printer and it worked! Hope this helps!