We have a Laserjet M602dn that has recently started skewing all printed pages. At first, we thought it may have been the new brand of 3rd party toner we were using, but moving the toner to our other printer does not cause the same issue. I have checked all paper tray settings, and swapped out the tray from our other functional M602 with the same results. I've replaced all pickup rollers with new. I've also pulled out the duplex unit. The skewing occurs from both tray 1 and tray 2, so I settled on swapping the registration assembly.
We have another (3rd) unit in the back that I use to pull parts occasionally, so I swapped out the registration assembly from that unit, again, with no effect. I also swapped the fusing assembly from my parts unit. Nothing.
So, to summarize:
Skewing from trays 1 & 2
Checked adjustments on paper tray
Replaced toner from known good printer
Replaced paper tray from known good printer
Removed duplex unit
Replaced all pick rollers with NEW
Replaced Registration assembly from parts unit
Replaced Fuser from parts unit
One final note...this printer has 1,627,863 prints on it.
Honestly at that page count, walk away and replace it. Life rating on that engine is only 750K. You will exhaust more labour trying to get it working than it is worth. Just my opinion.
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