Phaser 740 paper jam coming out of duplex

[CraigTM]

I have a paper jam that I can’t figure out. If anyone knows what is causing it, I would greatly appreciate knowing. Before I explain the nature of the jam, let me say that I have two Phaser 740 printers. One works flawlessly. I have traded the duplex unit and the paper feed unit from the good printer to the bad printer and the problem remains.

When printing duplex, or when printing a single side that the duplex unit turns over the page before depositing it on the output tray, the paper feeds from either the lower or bottom paper tray, prints, passes through the fuser, then it follows the path that feeds it into the duplex unit. The page goes out the duplex unit and exactly at the feed rollers of the paper feed unit, it stops and jams. This leaves about one third of the page in the duplex unit. .It is as if the paper feed unit only knows to feed paper from a tray, but not from the duplex unit.

 

[CraigTM]

We fixed the problem. I was able to find a 16 CD set of printer service manuals that covered several manufacturers, on Ebay for $50.00. The problem was very simple to fix. At the very end of the duplex unit is a little protrusion that fits into a sensor. Apparently, the sensor got banged and was slightly out of place. It easily snapped back into place and instantly started to work properly. There is a great menu to view that cycles through all of the sensors, solenoids, motors, etcetera, which found the problem. To access the menu, press and hold the third button from the left, on the front panel, while turning on the power. Follow screen instructions.