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06-17-2010, 04:15 AM
Anyone have experience with bizhub 600? full of black background after copying. I've already try TCR adjustment but still same result.
Any Solution?

06-17-2010, 06:18 AM
Check your charge corona? Got bias on the mag pole? Got an image on the page at all?

06-17-2010, 09:02 AM
sounds charge related

06-23-2010, 10:25 AM
1. Background
While analyzing the problems (toner spill and gray background on bizhub 750/600) reported from the field, BT found that the magnet angle of some developing units is out of its standard.
As the result of the cause investigation, it is found that there was a problem with developing unit magnet angle adjustment jig in the manufacturing process.
Status: the magnet angle is approx. 6 - 8 degrees. (approx. 2 - 4 degree high tendency against standard value 4 +/- 1 degrees)
If the magnet angle becomes larger, developing ability slightly decreases and toner density increases approx. 1 - 2%. It tends to make toner spill worse.
However this problem does not occur on the all machines. It occurs depending on the machines.


[Subject] Toner spill [Description]
Both or either of corners at leading edge of paper are soiled black.


1. Toner density is high.
2. Paper that generates much paper dust is used.
3. High CV.
4. Low coverage print.
Note: 1 is a factor on machine side. 2 through 4 are factors of machine use condition of user.

Perform the following.
1. Check the developing magnet angle again and adjust it if necessary.
2. Clean the toner recycle section, drum peripherals and paper feed path.
3. Clean the paper dust removal brush.

If gray background is also occurring, perform the following.
1. Change the dipswitch 23-2 and 23-3 from 0 to 1. (This decreases toner density by 1.5%.)
2. Output the test pattern No.12 on A3 in duplex mode. (25 to 30 sheets)

If the problem persists, perform the following.
3. Change the dipswitch 5-0 from 0 to 1.
Note: This decreases the toner density further. However, it also decreases the image density. Do not perform this for users who wish dark images.


[Subject] The machine is spilling toner onto the T/S corona unit. [Description]
PROBLEM: The machine is spilling toner onto the T/S corona unit.


CAUSE: The toner control sensor board has failed. This causes the toner to be unregulated and spill into the machine.

SOLUTION: Replace the toner control sensor board (p/n 56AA 910 2E) as well as the developer to correct the problem.

06-23-2010, 09:43 PM
...you must see the conts off the drum ...and de developer ...are they old ???

...probably is de first corona ,check the grid clean or replace the grid but the better is change the corona unit .
-never do a TCR adjustment in a old developer ...(or not new)--
-and cold be off course a problem of HV......tray to adjust it in 3-6 mode

06-24-2010, 09:40 AM
Thank you all
I will try them.

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