Message: Error paper jam. There is no paper jam.

With commercial machine like the ImageRunner, it is often staff roughly removing the jammed paper and leaving a tiny piece of torn paper over one of the sensors.

Remove the wall mains plug. Remove all the paper trays. remove the toner cartridge, open all the side doors and look carefully with a flashlight for a small piece of paper.

List of Error Messages - imageRUNNER ADVANCE 400iF 500iF

https://oip.manual.canon > ... > Problem Solving
Error messages are categorized by function. Select the function that corresponds to the displayed error message, and see the possible causes and remedies.

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  Clearing Paper Jams - imageRUNNER ADVANCE 400iF 500iF

  https://oip.manual.canon > ... > Problem Solving
  Follow the instructions on the screen to clear the paper jam. The screen is displayed repeatedly until the paper jam is cleared. If you press [Close], you can ...

check the sensor

To clear the error message Paper Jam after you removed the jammed paper, open and close the scanner cover.
If you still receive the error message, a small piece of paper may be stuck inside your Brother machine.

Refer the below link for the steps to remove any ripped paper remaining inside your Brother machine:

still receive the error message Paper Jam after removed the jammed paper...

Reboot it. Unplug wait plug it back in

Dell 2135cn All-In-One Laser Printer paper jam

If message in display panel reads [13.XX PAPER JAM [LOCATION]]Media is jammed at the specified location (and possibly at other locations). If the message persists after all jams have been cleared, a sensor or sensor lever might be stuck or broken.
Soln.
For all jam messages, do the following: 1. Remove jammed print media from the specified location. Check the entire paper path for other pieces of media in the path. 2. Open and close the top cover to clear the message. 3. Check sensors and flags in the paper path for proper operation.

For message 3.0 PAPER JAM [LOCATION]
means A non-specific paper jam occurred.
Soln
1. Remove jammed media from the specified location. 2. Verify the paper tray is fully closed. 3. Inspect and/or replace the feed and separation rollers. 4. Ensure there is no obstruction in the path, such as a torn piece of paper. 5. Open and close the top cover to clear the message. 6. Check sensors and flags for proper operation.

For more help check yhis site

http://www.printertechs.com/tech/error-codes/error-codes-0-19.php

This error message is displayed by the printer when paper is jammed in one or more locations. In such a case, users are recommended to remove the jammed paper from the specified location. The entire paper path must be checked for any pieces of paper. To stop the message, open and close the top most cover of the printer. Lastly, verify the flags and the sensors. If the problem persists, the cause of the error message could be a broken sensor or sensor lever.
http://h30434.www3.hp.com/t5/Other-printing-questions/Paper-Jam-Error/m-p/305772#M20513

Hp paper jam error message is displayed by the printer when paper is jammed in one or more locations. In such a case, users are recommended to remove the jammed paper from the specified location. The entire paper path must be checked for any pieces of paper. To stop the message, open and close the top most cover of the printer. Lastly, verify the flags and the sensors. If the problem persists, the cause of the error message could be a broken sensor or sensor lever.



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look at the paper tray,some of your sensor are jammed,try tyo find out where is the sensor on paper try

Please check rear door area for paper, can you use manual feed slot? Power off machine with all jams removed and paper loaded, then power on, can you tell us exact error message/lights that are shown in this state?