MR-4000 width size problem

[sappa12]

Hello, has anybody deal with this "problem" when you put A4 sheet on a tray and align the guides and press start , machine sometimes detects A3 format instead of A4. When i test width sensors in 03 mode all three values A,B,C blinks at the same time when i gently move the front guide . I dissamble upper tray,check PWA board, everything looks good (dont know the reason for 7 washers (5 at the front and 2 in the rear groove lol)
I tested few MRs and when everything is fine values go from A to B and C....when all three blinks i soon get this wrong format

[blackcat4866]

The time I saw this was a new installation. During manufacture Toshiba dropped dozens of those clear spacers inside the original tray. Raising and lowering the DF caused them to move around inside the tray. Naturally mylar plastic shims do not make a good conductor. I just removed all the extra spacers. Since they are clear, they are difficult to see. While you are inside the original tray, reseat all the connectors that lead to the conductor board. =^..^=

[arnh79]

We've replaced at least 10 of those PWA boards that detect the width for that exact problem. Seems there was a run of bad boards.

[MarioTech]

There's a bulletin TSB-2011 that fixes these issues, unless of course the board is blown. Hope it helps

[Rusty.Harris]

We noticed a few of these doing similar, and i tracked it down to the lighting in the ceiling above the machine. If I took an 11x17 (A3) sheet and held it a foot above the RADF
it would detect fine, but with the lighting hitting the sensor, it would pop up A3 (11x17).
Also, as mentioned, double check that sensor. That window gets clouded up easily.

[Cusefan81]

Alot of time you don't need to replace that board just clean the contacts and bend the prongs I've fixed 100s like this and maybe replaced 2

[djbass]

Sometimes there is excessive grease on the board with the sliding contacts, usually a good clean, and as Cusefan81 mentions reforming the springs for better contact will fix it.