C353 - Ocasinal gray background on lead edge w/ developer

**Stirton.M** · 07-02-2010

This looks like a very unique issue.

At first glance, bias would be my immediate guess. But the negative image on the right side of the page (lead edge) tells me that something else is wrong and that the laser write process has reversed into a negative image.

Just out of curiosity, if you were to copy a good page off the glass and set the machine to give you a negative image as an output, what does the output document look like? If it is the opposite of the images you posted, I would say replace the PRCB/MCB. It might even be memory related.

**mrwho** · 07-02-2010

First of all, I should've explained (for those who didn't check the other thread's attachment) that the ICP5 controls the belt resetting (the original problem I had, again on the other thread), the fusing unit resetting and the drum's erasure lamps - which is what caused all this trouble.

Answering Stirton's question, I never really tried that exact test, but I did try some other thing: When trying to troubleshoot the issue, I disabled the black IU's charge corona (using scotch tape over the contacts) and tried to make a copy. Without the corona, the machine should've output an entirely black sheet (if I'm mistaken, please correct me), but in reality the output came black on the left (the "good" area) and with the text partially visible on the right. This led me to believe that the erasure lamp wasn't working because the drum still had some charge from previous copies.

I'm sorry if this sound confusing - even now I'm reading it and I'm getting dizzy. Good thing the weekend's here! \o/

**Stirton.M** · 07-03-2010

Ya, sorry about the answer. I was going based on your earlier post before you put in the details about the ICP. I had opened up this thread to reply earlier, was interrupted and came back after. And obviously right after you found the cause and solution by a mere couple minutes.

Tape eh? I'll have to add that idea to my mental toolbox.

**mrwho** · 07-03-2010

No worries, I'm just glad this is over. Thanks for every feedback.

About the tape, I don't see the need to add it - every customer of mine has some lying around.