C452 with solid black background

[rindraintsoa]

hello all,
I have a problem with my C452, there is a solid black background in every copy/print as you can see in the sample,
I have put the drum unit on another C452 and the print is good (no background) so I thinked it was the developing Unit, replacing the developing unit with a new one the problem persists (black background) I took care about the poisitioning of the drum but the problem persists. Anyone have an idea about this problem?
Thank you very much in advance.

[wseyller]

Re: C452 with solid black background

Do you see this on the drum itself? If so block the laser and then if you still see it then likely a bad contact to high voltage or the HV board itself.

[blackcat4866]

Re: C452 with solid black background

Do you see this on the drum itself? If so block the laser and then if you still see it then likely a bad contact to high voltage or the HV board itself.

Yeah, I was leaning towards primary charge contacts also. Notice that there is no void on the front or rear. Those voids will be lost is primary charge is weak/lost. =^..^=

[wseyller]

Re: C452 with solid black background

And I just threw in covering the print heads for the hell of it. Because if it is known for sure the combination of the drum and developer is doing that by itself without interference from the lasers, and it is known the drum/Dev unit are good then high voltage is the only thing I can imagine. And it looks like charge on drum is bad too me.

[allan]

Re: C452 with solid black background

Yea im with BC on this does not seem to charge up the inconsistent lines is a give away. Just do a half tone at "0" to test for bias problems.

[allan]

Re: C452 with solid black background

Yea im with BC on this does not seem to charge up the inconsistent lines is a give away. Just do a half tone at "0" to test for bias problems.

Thinking like my hind side halftone print would just do the same.

[rindraintsoa]

Re: C452 with solid black background

Thinking like my hind side halftone print would just do the same.

if the printout with halftone is the same what to check in this case? Suppose the HV unit?

[allan]

Re: C452 with solid black background

No follow BC's advice and check the charge connections. You can even replace the IU to test. There is problems with the way the IU k mounts there is a fix out on that. A while back one of our techs just reseated a unit to fix black prints.

[carra]

Re: C452 with solid black background

No follow BC's advice and check the charge connections. You can even replace the IU to test. There is problems with the way the IU k mounts there is a fix out on that. A while back one of our techs just reseated a unit to fix black prints.

HOW I RESET K UNIT?

[carra]

Re: C452 with solid black background

anyone fix this problem?

[joelea]

Re: C452 with solid black background

if the printout with halftone is the same what to check in this case? Suppose the HV unit?

Hi did you ever fix your original with the background, we are having a similar problem with a c452.

[carra]

Re: C452 with solid black background

fixed that just reconecting laser flat cable on left side on machine.