C450 light prints, all colors washed out

[Haroldbfix]

The machine will not stabilize it dispays NG. Also display p6-9 codes. All IU and Transfer belt has been replaced however they wont reset because the machine cant stabilize. Also the PWB-MC board was replaced (the first board you see on the right when the rear cover is off).. Firmware was reloaded.

Im thinking the LED unit is faulty or the HV unit. Any Ideas? I have a show down with this beast tommorrow!

[JSC]

I'd check for blown ICP's, other than that it sounds like a bitch of a fault.....................

Good Luck

[emujo]

Just went through this last month..B&W copies not too bad, but color almost completely faded, Image stabalizer fails with NG. Same pcodes. Blown IPC on Overall Control Bd that controls developer bias circuitry. Very easy to check... Remove rear cover and (with power off) test continuiy of all IPCs on board. Don't remember which # it was but think it was at the bottom of card. If you find an open IPC, replace main bd. You might be able to find one at HighTech for a good price. Had to replace all 3 color I/U after board replacement. You might have to do a firmware update to bring the rest of the MFP firmware up to date with main bd. Good Luck. Ed

[Haroldbfix]

Just went through this last month..B&W copies not too bad, but color almost completely faded, Image stabalizer fails with NG. Same pcodes. Blown IPC on Overall Control Bd that controls developer bias circuitry. Very easy to check... Remove rear cover and (with power off) test continuiy of all IPCs on board. Don't remember which # it was but think it was at the bottom of card. If you find an open IPC, replace main bd. You might be able to find one at HighTech for a good price. Had to replace all 3 color I/U after board replacement. You might have to do a firmware update to bring the rest of the MFP firmware up to date with main bd. Good Luck. Ed

OK thanks, I just realized I replaced the PWB-MC (4037780303) not he MFP (4037013104). all the icps on PWB-MC were good. I still have the oridinal board in my car I will recheck them again, just in case I missed one. Can you give me a part# for the board you are talking about. AND THANKS!!

Ps curious why replace the IU's again?

[edmund]

please check for developer consumption on this machine .is the the colours bad on on colour only e.g. cyan ,magenta .We had a case where the developer was consumed and it was the bias connact that was rusted.China had the same problem on a small machine.problem Humidity
Please check the hopper unit as well we have plenty hopper prolems were the toner cloggs in this unit ,once again Humidity being the problem

[xcopy]

Check the metal contacts on the transfer roller and the flat metal spring under the transfer roller, clean both contacts and also clean the HV contacts on the transfer belt and where they touch on the inside of the machine.

[B0265]

Ps curious why replace the IU's again?

Had this once on a C350 and once on a C450, what happens when the ICP on the PWB MC blows is that the IU's get drained of developer.
On the C350 it was ICP 17, but I'm not sure about the C450.
Does anyone have a list of the ICP's for the C450?

The pic below is from the C350.

[JSC]

Does anyone have a list of the ICP's for the C450?.

Hope this helps.

[abilashvk]

hi friends,
It's a story of another bizzzzzzzzzzzhubbbbb color.Hope whether this will do any goodys?

http://www.copytechnet.com/forums/konica-minolta/20645-p8-p7-p21-c-250-a.html

[Si@danwood]

Ermm i suppose the i.d sensors have been cleaned and the shutter is working correctly?..Si

[lucky13]

try one of these

[Haroldbfix]

Thanks everyone for all the suggestions. The problem turn out to be a faulty HV unit. The previous tech allowed the machine to be down for two weeks before he said something. So I didnt take any chances, I replaced both HV's ( a pain in the butt to get to them!)

The IU developer had been sucked out! The toner collect box was unusally heavy (full of Developer) I will replace them tommorrow.