Dp Swich List for KM C452

[Synthohol]

does it happen on all 4 colors?
i gotta check, i think it was the c452s that had the printheads "recalled"

[Canonier]

the carton paper effect
(the lines in gray).

[Canonier]

No, only in black.

[habik]

Wasn't this caused by drum drive? or was it on different model.. Think I've seen thread about this.

[Canonier]

No the drum drive is brand new. and the dev unit also.
this lines i think are from the movement of the transfer unit somehow.
if you use thick 1 paper mode. the lines are improved drastically.

[habik]

No the drum drive is brand new. and the dev unit also.
this lines i think are from the movement of the transfer unit somehow.
if you use thick 1 paper mode. the lines are improved drastically.

Ah OK, What I was trying to say is the K DRIVE motor M18 for the K Drum speed is corrected by a encoder at the back of drive unit which when dirty can cause all sorts of issues. PS45 and PS46 are encoder photointerrupters. Saying that.., since the THICK 1 paper does improve the print that could mean the distance at the jitter is smaller. There could be drag in loop adjustments for the fuser. Since fuser speed is different on THICK 1 that may be half of your answer.
Thick 1 has 132mm/s
Plain has 216mm/s

Maybe worth trying to print as Gloss setup on PLAIN paper. i.e. to give the PLAIN paper a bit of shine. This will reduce the speed to 108mm/s and may show similar results as on THICK 1.

The fuser speed is also adjusted by the loop sensor which sits below fuser unit. I would probably check that if it isn't broken or just sticky. When you operate it manually it should have nice sort of plastic to metal resonance. If the shaft on loop sensor is soiled with paper dust or residue it is dragy/sticky and doesn't return as fast. If all good, then try adjusting the Fuser speed for PLAIN paper and see if the cardboard effect changes. Now I am thinking about it, have you tried print stop during paper passage between fuser and feed unit on A3 size? That could give some hints too.

I haven't found any Transfer belt drive speed settings.
FYI there is drive motor for Fuser and Drive motor for Transfer Belt.. so if out of sync it may cause issue.
There is DIP SW for Fuser to enable print job during alternating temperatures but I don't think that is related. DipSW S, Switch No.4 (Default is OFF)

Good luck.