C552 Cyan Image Unit failing

[copier tech]

Hi All, I have a really annoying fault on a C552 where I fit a Cyan IU in within 1-2 months & only about 8k the unit fails, it appears like the developer is lost (see picture) I can't see any leaked dev in the machine, so I'm guessing it's going into the waste box! all the other units go way over their life.
I've looked on the KM site & the only item on there is that there was a batch of faulty units with the lot number "A" this is about the 6th IU I have replaced in a year! The last unit I replaced was lot "B"

Anyone had this before!?

25002

[Max]

Do a continuity test on dev bias from the inside of the copier to a physical connector on the board. Also check the k drum unit for any K toner scatter on the frame itself. Check the IB make sure its clean on the edges. If all ok replace the bottom hv board, k dev unit and c iu again.

[copier tech]

Thanks, i've found this info on KM now.
The xfer belt is new, no K toner has leaked etc.
I've added some more foam rubber pads to the cyan latch i'm hoping this will help make better contact, what do you think!?
if it happens again i'll fit a new HV1

[copier tech]

I now have the exact same fault on another C552 now!
Has anyone else had this? I guess I'll do what Max said & replaced HV1, cyan IU & the K dev on both machines

[Rolandito]

Clean bias contact.....I had problems with dev units...because the bias contact was dirty...
Clean both (dev unit and machine)

[copier tech]

I cleaned all the contacts, they looked spotless anyway.

How easy is it to replace HV1, what do I need to remove!?

Thanks

[emujo]

Just about everything, take the manual and maybe some photos of the removal process. Emujo