Laser Jet 600 Image corruption Grapes of wrath bubbles circles

[john_600]

Intermittently this printer will print defective pages with random bubbles circles in random patters,

there is no help in troubleshooting articles on hp for poor quality printing examples.

I created a support post on HP support forum, printers, inkjet, here:

https://h30434.www3.hp.com/t5/Inkjet...ct/m-p/6305723

Some similar models show poor image quality sample saying droplets on page problem/
cause due to humidity problem. this is not the case or issue at all.

searching online similar problems only came up with one article found here:

http://www.enxmag.com/twii/printer-t...r-contact-hp-l...

calling problem circle or bubble print, along with similar photo sample showing clearly the problem

the article refers to the toner metal contact posts on left side contacting with posts inside the printer

that the contacts could be bent not physically touching the toner cartridge or bent and touching the printer

metal frame.

After a test to see that the contacts are connecting, printing a page would show the defect at random times

and other times no defects.

When the metal tab is pulled away from toner contact it clearly does print the defect bubbles on the page.

There is no reference to this ground tab in the service manual no where that I can see and even in the part

description list there is no part showing for the toner contacts.

or any schematic map showing where these contacts actually connect to and or how they should function properly.

I have canceled out the cause being the toner cartridge trying other toner and problem persists

tried same toner in different printer same model and works with no issues at all.

this is not a fuser issue as also replaced and had same problems.

any help would be greatly appreciated Thank you in advance.

I do see similar posts with similar problems here with different printer models giving direction to the Laser image scanner

or high voltage power supply, one case someone replaced power supply and still had same problem

I suspect the Laser Image Scanner, has anyone with similar problem have success with this replacement?

[cs_steve]

That does look like a toner grounding problem.
On that model, remove the toner cartridge and inspect the cavity, on the left hand side you will see several small thin wires bent in a triangular shape, these are the toner grounds, as well as a long thin metal rod/wire sitting flush against the left side wall, which is also part of the grounding. If the triangular wires are "bent" then you can get the print defects in your photo; also if the rod/wire sitting on the wall is stuck in an incorrect position it can cause unusual defects.

Alternatively, if none of those are physically bent out of place, the advice would be to replace the power supply board. We have them available at PrinterTechs, 866-352-7108.
Here is a link: http://www.printertechs.com/shop/rm1...m601-m602-m603