[Solved] MK3S upgrade filament sensor not working  

MK3S upgrade filament sensor not working

I upgraded my MK3 to MK3S recently with the upgrade kit that included the printed parts. I didn't notice until weeks later that the filament sensor doesn't work. In the sensors menu it always shows a '1' whether or not filament is loaded. I tested the sensor by removing the top cap and freeing the sensor board and blocking it manually with a piece of filament (it works fine in that case). I disassembled the print head and checked for free movement of parts, magnet orientation (opposing), etc. An hour or so later after having assembled it I tried it, and once again it always thinks filament is present.

I removed the cap and filament sensor again and looked at the mechanism inside. It appears that the lever part that pushes against the ball bearing is not able to move far enough to the right for the 'fin' to unblock the IR sensor. I am not able to push it farther to the right either (with no filament inserted of course). When I put filament in from above the lever moves left, but only a small amount (maybe 1.5mm).

Could someone possibly remove the cap and filament sensor from their MK3S and take a photo of the lever part from above, both with and without filament inserted? I'd like to get a better idea of how far the lever is supposed to travel.

Any other tips are appreciated.

BTW - I couldn't find a way to work in this part of the extruder without quite a lot of disassembly including removal from the X chassis. Hopefully I'm missing something and there's an easier way to get to the filament sensor chamber.