Bizhub c308 no Black

[dragonman]

Now feeling utterly frustrated. We lost the k image on the above machine and we have replaced the k drum and dev and hv board still no black. Each time I add a dev tank it empties the dev out bit by bit by dragging it to the drum and recycling it through the t belt. I've tested the 24v lines from the MFP and all is good checked continuity on the dev bias and drum charge.

Now running out of ideas. Has anyone any good suggestions?

[Synthohol]

Are you getting transfer to the belt at all?
Internal test pages are blank?
Not for nothing, in the US konica has a 3 year bumper to bumper warranty.
Maybe get them involved?

[dragonman]

Are you getting transfer to the belt at all?
Internal test pages are blank?
Not for nothing, in the US konica has a 3 year bumper to bumper warranty.
Maybe get them involved?

The only thing I'm getting is random dev transfer to the drum and belt but no toner image. If you print the meter readings it come out completely blank

[Synthohol]

is the drum turning? is the connector from dv unit secured in the FSB? when you turn the dv do you get a good brush?

[blackcat4866]

Recently I had a C658 that had no yellow and magenta. When I changed the developing units, the machine sucked the new units dry of toner in less than 10 seconds. I ended up changing the HVT along with another four developing units. =^..^=

[copier tech]

So after you first replace the K image unit & dv the machine will print OK?
How long before all the dev is pulled out?

Firmware often gets dismissed however it can surprisingly rectify a number of weird issues like this.

[REGSIS]

is the drum turning? is the connector from dv unit secured in the FSB? when you turn the dv do you get a good brush?

Drum is turning otherwise developer couldn't be depleted.
If connector is loose or not connected error would appear on screen.

@dragonman
When you replaced a new dev unit K what was the printout like. What's the trc state for black.
Any error after stabilization.

[dragonman]

Drum is turning otherwise developer couldn't be depleted.
If connector is loose or not connected error would appear on screen.

@dragonman
When you replaced a new dev unit K what was the printout like. What's the trc state for black.
Any error after stabilization.

When you replace the dev and print out the birdie test page all registration is out and you just get a smear of black across the page. TCR is reading 6.7. No errors except for the oil can in stabilisation. If you look at the two attachments one is the copy page and the second a voltage readout does this help?

[REGSIS]

Your first image have some black (minimum). Next few images and black is completely gone.
Am I right.

Your developer is not depleted. Your black dev unit is not rotating.
On the back of the machine remove right and left covers and right rear cover. Unscrew all M3 screws, remove 3 connectors and open PWB box. Remove dev motor and check solenoid behind it. It's stuck.
Either replace the sponge with piece of cardboard cca 1mm thickness, or replace the whole solenoid.

I had exactly the same problem on c224e.

After turning on the machine stabilization should run automatically and colors will be aligned.

[dragonman]

Your first image have some black (minimum). Next few images and black is completely gone.
Am I right.

Your developer is not depleted. Your black dev unit is not rotating.
On the back of the machine remove right and left covers and right rear cover. Unscrew all M3 screws, remove 3 connectors and open PWB box. Remove dev motor and check solenoid behind it. It's stuck.
Either replace the sponge with piece of cardboard cca 1mm thickness, or replace the whole solenoid.

I had exactly the same problem on c224e.

After turning on the machine stabilization should run automatically and colors will be aligned.

thanks for the reply. I have checked the dev solenoid as once I'd replaced the hv board I left the back cage loose and I could quite clearly see the solenoid activating and the gears rotating.