Light toner on drum

[sbtiti]

Please help! Any general info would be appreciated... Working on a WorkCentre 4260 which copies grey instead of black. It appears that we're not getting dense enough toner on the drum. Problem has nothing to do with the scanning so it is in the Xerographic process. New drum and toner have not fixed the issue.

Would you suspect the HVPS? What else can I check? Thank you for any help.

[Exok]

Re: Light toner on drum

The only cases of this I have encountered were due to the drum cartridge failing too soon. In every case I have seen this in, replacing the drum corrects the problem.

If a drum was replaced and the problem was corrected but only for a short time, inspect that the toner dispense motor is turning. The problem in this case can be the motor or the power supply unit 1.

If the new drum didn't correct the problem even at the 1st print, try inspecting / cleaning the laser unit window.
You may have a faulty HVPS.
Check the spring contacts of the transfer roller assembly.
Try reseating connections on the Power supply, HVPS and main pwb.
Check the spring contacts in the terminal assembly that supply voltage to the drum and side cover assembly.

[sbtiti]

Re: Light toner on drum

I was able to check the HVPS in another 4260 and it worked fine, so it's not that. I checked electrical continuity between the contact points that go thru the terminal ass'y that seemed fine. I opened the LSU and cleaned mirrors and lenses to no avail. I also checked the SMART drum unit in the other 4260 and print was dark. I'm not sure where to go from here.

Has anyone ever run into a laser scanner unit that works, but has a weak laser?