My brother mfc 240c says paper jam while there is no papaer jam but i start it becomes noisy and stop

SOURCE: paper jam, and I don't

I had the same problem.  I had removed all the visible paper and when it came back on made some awful noises and flashed "paper jam".
I even moved the roller forward and backward (after having uplugged the device.  I did this repeatedly and the "paper jam" alert continued (along with the awful noise).
As a last resort I thought I would just take it apart and hope to get it back together but figured it was a sensor or something along that line if I could not find any paper anywhere 

with the machine unplugged (it would not shut down), I opened the lid I used a flashligt to look around trying to figure out how to take it apart.
It then dawned on me that I had not moved the print head over and using a screwdriver I gently pushed it to the center of the bar.  When I looked inside with a flashlight, there was the paper jam way inside under the cover.
I used some needlenose to reach in and took the paper out and it is now working fine.
I hope this helps, but you may have to search really deep into the device.

SOURCE: what is 'print unable 51' never had a paper jam!

Do the following:

Print Unable
XX
The machine has a mechanical
problem.
—OR—
A foreign objects such as a clip or
ripped paper is in the machine.

Open the scanner cover and remove any foreign
objects inside the machine. ( You might try cleaning the scanner glass.)
If the error message continues, disconnect the machine from
the power for several minutes and then reconnect it.

Try this and let me know what happens. Binary Bob

SOURCE: BROTHER MFC-240C,UNABLE TO CHANGE 50

This error is usually caused by the Carriage Encoder Strip being dislodged from
the sensor mounted on the Print Head/Carriage Assembly.

Unfortunately, you will need to remove the scanner assembly, and top cover assembly to check to see if the encoder strip has come out of the printhead assembly.

SOURCE: Error 50 after jammed paper on brother MFC-240c

I had this too, I had to open the back of the machine, it is meant to open and pull out and clear the jam (pull out the crinkled paper) but everytime I tried to print again it kept saying that it still had the jam, I opened and closed it several times and it did not seem to register that I HAD CLEARED THE JAM, so what I did was unplug it from the wall and then plug it back in and then it was fine. I wonder if this is AN ACTUAL DEFECT with this machine, if ater a paper jam it cannot detect that it has been resolved without having to unplug it and plug it back in, HOPE THIS WORKS FOR YOU.

SOURCE: Error 30 after jammed paper on brother MFC-240c

Open the front and the rear panel and make sure there is no bit of paper jammed. Also make sure there is no dirt in the printer roller