I have a Brother MFC-7860DW that always reports "No Paper" (slightly different from this question, which reports "Paper Jam"). When I open the letter tray, the paper just barely starts to grab the rollers. I have tried following the instructions in this Brother Brother MFC-L2710DW No Paper Error video to no avail.
There are several similar models to this printer which seem to exhibit the same error:
The problem is likely that the Brother Feeder Cam Lever (part LY2579001) is either broken or slipped out of position. One user reported it's possible to fix without disassembly):
This is small plastic piece that is used to lift/lower a gear in order to start and stop the feeder rollers. This lever can come out of position such that it can no longer wedge beneath the gear, and instead pushes against the side of the gear. Thus, the feeder rollers will no longer work.
I was able to fix this for a little while without disassembly. Later the same problem happened. I removed one screw and a side panel to expose the cam. Sure enough, it was broken. See this video which shows how to access the Feeder Cam for Brother printers MFC-7360, DCP-7055.
I found a replacement Brother Feeder Cam Lever (part LY2579001) on Amazon for $5.95 which should keep the printer running.
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