Printer Faults - Irregular White Dropouts

Irregular areas of dropout are most likely to be due the type of media that doesn't suit the printer. If there isn't any question about the media it could possibly be a voltage issue.

The lack of regularity to the pattern of fading doesn't seem to indicate the rollers are an issue, If it were the dropouts would have a pitch to them. Check that there is no pitch, for instance a fingermark on a precharge, OPC or transfer roller will look blotchy but actually have regularity about it. Patterns just a bit more regular than this would suggest a damaged transfer roller

Fading due to a voltage fault might be expected to affect the whole page or one side of it.

An irregular pattern suggests the print media doesn't suit laser printing. The first thing to check is probably to check the media types against the user manuals list of settings to see if there is one appropriate to the job.

Paper with a rough surface often can be laser printed but the user may need to select a heavy paper type to improve fusing. There may also be one or more fuser high settings. Not all of these modes might be available from the driver in which case they may need to be set from the control panel menus.

If you do set a high fuser temperature then remember

• check the media can take a higher temperature - transparencies can melt and that wrecks the fuser.
• set it back before using ordinary media or you may get some measure of offsetting - echoes of the print job appearing on the page.

If the fault happens with media that most certainly should print such as 80gsm A4 paper then try the usual things with the paper first: - try another ream, turn the paper over, turn the paper the other way up. Paper kept in unusual circumstances such as being too hot and dry might suffer this sort of problem.

Try a Stop Test

One approach to tracking the problem down is to try a stop test.

Set a configuration page or whatever clearly shows the issue away. Wait a short time until you are sure the page is passing through the print station. At this point open the print-cartridge door creating a deliberate paper jam. Carefully examine the resulting page - does it show the fault? Look into the print cartridges, part of the print material will still be on the OPC drum. Does the OPC show the fault?

Does the fault only occur after the fuser? If so are there signs of toner transferring onto the fuser rollers?

If there is no other solution fall back to the usual solutions for fading. Try turning the print density up a bit. Clean the innards of the printer, check any corona wires.