I found this problem on a Brother MFC 8820D, but it may also apply to it's sister models: MFC 8420, DCP 8020, DCP 8025D, and DCP 8025DN.
Symptom: When you insert a document into the feeder to scan, fax, or copy, it recognizes it, but when you touch the Start key, it barely twitches, then says Check Original, as if it had jammed. You can pull the document out, touch Stop, and try again as often as you want, but it won't feed.
In my machine it turned out to be just a glitch in the memory. It cleared up with a Memory Clear operation:
You need to enter the Maintenance Mode. Here's the easy way on the MFC 8820D; other models may have different keyboards:
- Turn power off.
- Press and hold the Menu button.
- Keep holding Menu down while turning the power on.
- The machine appears to start normally. Keep holding the Menu button down until the words Please Wait disappear. Then release.
The word MAINTENANCE should appear on the display, while all lights flash in unison.
Maintenance Mode allows you to commit all kinds of crimes against your machine, all by entering just two little digits. Don't mess around - just clear your memory and get out. If you start to enter the wrong number, touch Stop, then enter the correct number.
The code for clearing your machine's memory is 91. That's it. You don't touch Start or Set or anything else - just the two digits. The 91 code initializes the EEPROM, but leaves your phone directory and your own name and number intact.
It will take a few seconds to clear everything, then return to MAINTENANCE. You have two ways to get out of Maintenance Mode: you can touch 99, or you can turn the machine off, then on again. Either way, it will go through it's entire warm-up routine. When it's done it should be fine again.
A similar problem can occur if a gear falls off one of the document feed roller shafts under the rear top cover. That's a different problem altogether.