HP M507 print alignment fluctuates, jams

[jeffshead]

I created a thread (https://h30434.www3.hp.com/t5/Printer-Paper-Jams-Feed-Issues/HP-M507-print-alignment-fluctuates/m-p/...), for this same issue, a year ago but it is closed.

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I have a M507 with three 550 sheet trays including the built-in (trays 2, 3, 4).

Issue described below does not occur when printing from manual feed tray nor trays 3 and 4.

When printing from tray 2, the top alignment of the print (start of print) varies from page to page.  It can vary up to 3/16". It does this with all print jobs even the onboard tests. For example, if I perform a paper path test of five pages, the start of print is different on each page. It varies from correct to too high on the page. I don't recall ever seeing the start of print being too low on the page. It hasn't jammed nor thrown any errors.

I have replaced tray 2, replaced the pick and separation roller assemblies, replaced both pick solenoids on the right side of the printer, made sure the paper path is free from debris and adhesive, made sure paper settings and tray guides are properly set.

Maybe I'm wrong but I don't think it's the registration assembly since this issue does not ever affect print jobs from the manual feed tray nor trays 3 and 4.

What could be causing this... Paper feed motor, formatter, DC controller??? What's my next step other than throwing parts at it?

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Since then, I have encountered this same exact issue with four different printers (M506's and M507's). This issue also occurs with the option tray assemblies.

Because HP has such a limited list of replacement parts which can be ordered for this series, I have had to replace some of the printers and option tray assemblies. That has been the only remedy. This must be a known issue. I can't believe I'm the only one reporting it. To me, it seems to be a sensor/timing issue. The printer thinks the paper is where it is supposed to be and starts printing even though the paper is not there yet.

I have also had a person from a large managed print service provider tell me that they have been getting a lot repair tickets for this series for these same types of jams.

To reiterate, this same exact issue can occur with tray 2, 3 or 4. When I see this happen with an option tray assy. (tray 3 or 4), I swap the position in the stack and the issue always follows the assy. Swapping or replacing only the paper cassette and feed/separation rollers has never made a difference so the issue is either a sensor, pick arm or drive assembly problem.

[jeffshead]

Just today, I had to replace another option tray 3 due to jams and 13.B2.D3 errors on a M506DN.