wierd random image shift on duplexed side

[zubinn]

c7000 konica machine, printing simplex is okay.

Printing duplex on the reverse side the image randomly shifts 5mm inboard perpendicular ( 90 degrees ) to the paper path.

InkedIMG_20180413_1116092_LI.jpg InkedIMG_20180413_1115286_LI.jpg

[allan]

You shift is in the "main scan" direction.
Clean or reconnect the centering sensor.
Don't know these well.
Could be skewing before the registration and shifting after the loop.
Don't these machines jam if the centering is out too far, soft-switch turned off?

[zubinn]

how can i check if the image shift is due to a mechanical issue i.e. the paper physically is shifted higher.

[allan]

check at the paper exit