hi folks,

i have a Samsung scx-4521f b&w laser printer which the service manual can be found here.

on page 100 section "6.2.3" titled "JAM 1".

it says 1. If the recording paper is jammed in front of or inside the fuser. => Replace the SMPS.
2. If the recording paper is stuck in the discharge roller and the fuser just after passing through the Actuator-Feed, Feed Actuator may be defective. => Reassemble the Actuator-Feed and Spring-Actuator if the returning is bad.

not sure what this means but here is my diagnosis.

any time the printer tries to print something the paper gets stuck in the area which is displayed in the image (in pink) on page 99 of the manual (section "6.2.2" title "JAM 0").

i have disassembled the printers roller kit and was able to find 3 things.

1.
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- the bar here for the paper sensor seemed to be bent out of shape, so i re-bent it back in to place.
2.
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- this button seems difficult to push
3.
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- and not sure how important the alignment of these pieces are. the outer piece as shown in the picture wasn't tightened and slides back on.

i did not re-assemble the printer back together, i wanted some advice before i close the printer on other things i can attempt to do to fix it.

also note, that when the error occurs for paper jam 1, it requested to open the front door than close it. so i do that, and than the paper feeds the page without problems, however its a blank page cause its just preparing for the next print, so i don't think there is something wrong with the rollers. please don't hesitate to ask me any further questions. this printer is a test project that im doing, never attempted to fix a printer before and i don't want to invest more than 20-30 dollars MAX on a parts.

thanks in advance