Sharp 5111 black print problems

[Hansen88]

Its me again. Black print slowly fades away with each copy. Changed bk drum and entire primary transfer unit. Also changed bk charge kit and developer. Thanks for any suggestions.

[copiertec]

Is it only black? How do the rest of the colors look? Have you pulled out the laser unit and cleaned it? Is the developing unit turning?

[mansart]

Is this print and copy?

As above do copy in single color mode, what is result?

If you do a run of 5 and panic stop machine, what does image look like on the belt? is the drop out evident on the belt?

[Hansen88]

Developer is turning. All the colors look fine. If I copied a test page it is only the black that fades out.

[lgwilkinson]

I have seen the same thing on MX-4111 and MX-2600 they work for a long time in the field and then they start doing what you described. Not saying this is your problem but in my case changing out the MC PWB took care of the problem. There has been a few updates on this board. if you check out Sharp IDNC you can find the tech bulletin on it. Hope this helps

[leo34staffs]

Try to remove the laser shutter mech for black only for test purposes, im sure my colleague had a similar issue where the solenoid was not opening the black shutter fully (even though all colours are connected to the same solenoid), Removing the shutter may help or at least point you in the right direction.

[moose55]

I agree with leo34staffs. It appears to be the laser shutter. When they get toner and such into the ends of them, they tend to bind when opening causing exactly what your samples look like. There is a tech pub on this MFP-TB-308. It is not for the 5111 specifically, but it works for all with shutters.

[Hansen88]

Thanks for the suggestions. I am going back there in a few minutes. I have a MC PWB from another machine and I will try that first and if that does not fix I will look into the shutter. The only reason I am not sure about the shutter is if it only opened partially I would think it would block out the print kind of evenly across the page. Some test samples I have it might start fading in the middle of the page. Most times it starts out perfect copy and will fade with each copy till it is almost blank. Again, only with the black,colors working fine. I will give these things a try and see what happens. Thanks again

[Hansen88]

I went back there and it looks like the mc pwb was the problem. All my before test copies did the problem and all the afters were good. Hope it stays that way.

[repn1999]

There was an updated MC pwb for this issue in a bulletin...also affects the 5141. Looks like you already isolated it to the board but this was more of a FYI