C450i / MF 459 HV Problems.

**OlivettiTechnik** · 02-15-2022

Originally Posted by techsxge

I'll stick with english here, if you want to speak in german send me a pm.

Ok now this does look like the developer unit. Have you actually replaced the whole unit or just the developer itself?. To make proper measuresments, at what density have you made those prints?

We replaced the whole K Developer Unit. Nothings changed as I mentioned above.

Density print is normal. Improvement by increasing the Vpp-K1 and Vpp-K2 values.

INFO:
This week the Konica Minolta technical support will be around. Posting the results later this week.

**OlivettiTechnik** · 02-15-2022

Originally Posted by tsbservice

You've changed whole units(not only drum cylinder and/or developer powder) with new ones?
What should be on second page?

Yes we changed whole Units.

The second page is a service mode yellow halftone gradient print. The machine prints these black lines on everything.

**tsbservice** · 02-15-2022

Check PH unit(laser).

**tsbservice** · 02-22-2022

Any news on this problem?

**Gift** · 02-22-2022

This looks like some voltages went through the roof - I've seen this if you try messing around with used drums/devs (last case I had was with drums, kind of the exact image error).
Rotation time infos doesn't really indicate new units. If you put "newish" units into a machine with a high color volume and the machine doesn't reset them you end up into trouble
because the machine still tries to compensate a worn out OPC material leading to problems if the units are actually in a way better condition

I was able to recover this with fiddling with some voltages but can't recall the exact steps, sorry.

Guess you can also try and "chip" used drums - as long as they are really in good condition with low meter.

Start comparing the voltages with a working machine.

**Woxner** · 02-22-2022

The new drum voltage runs about 1700 to 2200. You can find this in table numbers in state confirm think its page 2. Vpp1. Closer to 1300 volts the drums are dead. If you put new drums in ck this

**and** · 06-10-2022

News ?

**REGSIS** · 06-13-2022

Originally Posted by and

News ?

I would place a bet on PH unit.
It seems to me there are repeated black regular shapes among all that blackness.

**and** · 06-13-2022

Originally Posted by REGSIS

I would place a bet on PH unit.
It seems to me there are repeated black regular shapes among all that blackness.

Update, but not solved.

I rechip drum K that print same "regular shapes". In my case "regular shapes" on K prints. K print now is good.
Some problem in color print (a lot of color dots) rechip drum C/M/Y but not solved. Increase VPP of C/M/Y remove dots but remaing some background on paper.

Life of drum was good.