Sharp AL-1631 misfeed light will not go out.

Not familiar with this particular model but I can tell you that every flag that the paper goes past has another flag at the other end of it's stem that blocks and unblocks a photoelectric sensor, these get clogged with paper dust which can be removed with a can of air. Just have a rag handy to block the dust and toner. You should also remove your developer tank and drum cartridge before you start spraying around (cover the drum or keep it out of the light). Take out your paper trays and make sure that there's no paper wedged behind it so that the motor cannot get turn it. Get a flashlight in the tight areas of the paper path and look for torn little bits. Mabye your rollers are dirty and need a cleaning with soap and water. It should be said that if you do not know how to do any of this without scratching your drum or spilling toner or developer, to just leave it alone and call for a service tech!!

Sensors are pretty much hidden and can't be accessed without taking the machine apart. You need someone trained on them to get to them.