MPC4502 with screwed colour gamma after ACC

[drwevil]

Hi
ive been having a problem with an MPC4502 and there is no contrast in the midtones after you do an ACC.
Copy is ok and printing max resolution is ok, printing anything else colour is crap.
If you then reset the Printer Application 5801-008 it comes good but if you do another ACC its bad again.

It has the latest firmware.

Any ideas?

[SargeNZ]

Re: MPC4502 with screwed colour gamma after ACC

Sounds like the ID sensors could be bad, but before that I would make sure the transfer belt, dev units and drums are all up to PM before replacing the ID sensors. Also clean the laser shield glass thoroughly (maybe remove the laser unit to do so) and make sure your scanning optics are clean so as to not throw out the ACC adjustment.

[slimslob]

Re: MPC4502 with screwed colour gamma after ACC

Instead of just using ACC from the User Tools, use forced line position adjustment in SP mode first, SP2111-003 followed by SP2111-001. When doing ACC from User Tools, always make sure that the optics and laser shield glasses are clean. Do Copy Function first, this will ensure that the engine, scanner and IPU are corrected calibrated. Then do all Printer resolutions. In the Copy Function, the pattern is fed directly to the engine to be printed. In the Printer Function, the pattern is fed through the printer controller and then to the engine. If the is a problem that has not been corrected for the Copy Function, the ACC does not have a proper base to adjust the Printer Function to.

[drwevil]

Re: MPC4502 with screwed colour gamma after ACC

all parts are with in PM.

Optics are clean, the forced line position works ok.

Copy is ok as is the test print from printer SP... C4 test chart looks brilliant.

One thing I didn't do was clean the ID sensors.

I was told by Lanier tech support to always do the print ACC first and I didn't think to try copy first.

Thanks guys its given me something to think about.

[drwevil]

Re: MPC4502 with screwed colour gamma after ACC

Fixed it... :-D

I did firmware and cleaned the ID sensors.. now it works great.

Thank for ya help guys.

[drwevil]

Re: MPC4502 with screwed colour gamma after ACC

well I got a bit carried away ...
This machine still has issues.

By Coincidence we had an MPC3002 do the same thing but in this case only the 9000x600 dpi ACC test pattern was affected.
Firmware was up to date and made sure the optics were clean. I reset 5801-08 printer application and it came good. Unlike the MPC4502 this one stayed good after the ACC. I was preparing to get all the SMC data for an official support request but it came good so I jumped for joy and went no further.

one thing I am going to do from now on, on these series machine is do the ACC then just print the test charts again just to double check.

see the attached image to see what an ACC test pattern looks like on a machine with this issue.

201409231306_0001.jpg
I still don't know the exact cause.....

[Smee]

Re: MPC4502 with screwed colour gamma after ACC

Dosnt corrupt NVRAM do this? Or the memory DIMMS? Think thats where I'd start - seems like the machines not holding or storing the ACC info.

[TonerMunkeh]

Re: MPC4502 with screwed colour gamma after ACC

I've got a 4502 doing exactly the same thing. In the process of doing the firmware now, I'll report back when I've finished faffing with it.

[Gamut]

Re: MPC4502 with screwed colour gamma after ACC

EEPROM on BCU needs replacing.

[TonerMunkeh]

Re: MPC4502 with screwed colour gamma after ACC

Have you had this before?

[Gamut]

Re: MPC4502 with screwed colour gamma after ACC

Have you had this before?

Yes, had to escalate to tech specialist who informed me of the outcome.

[TonerMunkeh]

Re: MPC4502 with screwed colour gamma after ACC

Cocking bloody buggering hell, I'll have to order one.

[drwevil]

Re: MPC4502 with screwed colour gamma after ACC

EEPROM on BCU needs replacing.

weare going to give that a shot..

Thanks

[TonerMunkeh]

Re: MPC4502 with screwed colour gamma after ACC

The fix on mine was the controller NVram. I've just had to do another on an MPC3502. I fucking HATE this version of the Apollon / Athena.

[drwevil]

Re: MPC4502 with screwed colour gamma after ACC

We fixed it ...
it was the Nvram on the BCU then set again form the birth certificate.....

One thing to try before you go to that extent is make sure the Scan registration is 100% correct as that can affect where the machine scans when it does an ACC so it samples in the wrong place ... that can throw out the printer gammas.