Xerox DCP-700 - 012-219 Error Shelf Home Sensor Does Not Turn OFF After Spec Time Aft

[g00r]

Hey folks,

I have a Fuji-Xerox DCP700 with light finisher that is having issues printing/copying when the output is the stacker tray.
I can print/copy to the upper tray and the booklet maker, but in the last few days, anytime I select the stacker as the destination, the machine will spit it out at the top tray, then will show error 012-219 on the screen.

I've had this machine for a few months and I was able to resolve this in the past through clearing out the stapler cartridge, hitting the reset button on the back of the finisher all while holding my tongue the right way. Several hours of fiddling later, the error persists.
My local tech has gone on holidays so I'm hoping I can work out what's going on before then.

I have taken three videos of the unit in operation in case this helps

Nextcloud

There's a video of intentionally printing to the upper tray, the unit starting up and then trying to print to the stacker.

I don't need stapling capability as a priority. If it's possible to bypass a sensor, I'd be happy to do this as a work-a-round until I can get a pro in to take a look.

[g00r]

Here's an update in case it helps anyone else...

I am currently still waiting on my tech to get back from holidays, so this was all just trial and error rather than intervention from a pro.

I have my unit in my garage here in Melb, Aus. The weather has been getting colder and I have been experiencing more and more paper jams when printing in duplex. Despite putting copy paper in a spare room to keep it warm, jams were still occurring more than frequently than my patience could handle.

I hired an industrial gas heater to dry out and warm up my garage and this greatly improved printing output.

Switching to manual duplex helped even more, and despite the manual intervention required, the machine was printing for several hours without a single jam.

Just out of curiosity, photocopying to the Stacker tray worked. I then queued up a big job to the stacker and it still worked. I was printing for about 4 hours without issue.
I took a break for dinner; the machine went to sleep. Upon waking up, the same 012-219 error reappeared. I tried rebooting, resetting (button on the back of the finisher) but the most I could get was a single photocopy before the error would pop up.

TLR I thought I would try heat, so I ran the gas (propane for the users of Freedom Units among us) heater for about ~5 mins, got the room toasty warm.
Rebooted the machine, the finisher & fiery. Sent a print job to it and it's running.

I'll update this post when I've finished my print job to see if I can replicate the resolution.