Bizhub 958 print very light

[otphas]

We have a issue with Bzh 958 , print is very very light , values in Level History 1 and 2 is normal. Also coming warning P-9 . Transfer belt and roller seems ok , ID sensor also was cleaned and seems ok. Any tips ?

[Toxic]

Some more info would be useful...
Counter, consumables life,toner OEM or some replacement...

[allan]

Post a half tone at 125 and 255. That also helps.

[tsbservice]

Too old developer? ITB 3 x over life?

[otphas]

Hi guys,

counter is 319K, all parts and toner are OEM and life counter is ok, no one part is over the life. Half tone or 255 doesnt matter, print very light

[femaster]

Hi guys,

counter is 319K, all parts and toner are OEM and life counter is ok, no one part is over the life. Half tone or 255 doesnt matter, print very light

One thing to check with output like that is to make sure the development unit / mag roller is turning. On some of the older models with a similar dev/drum setup, I've come across a few instances where the cog on the back of the dev unit broke, or the cog in the copier came loose, and the dev unit was no longer rotating resulting in output that looks just like that. An easy way to check is to take a cloth and wipe a small area on the mag roller bare, try to run a copy and then take a look at the mag roller again. If the bare spot is still there, you know it's not turning.

[Toxic]

Maybe check this

https://i.postimg.cc/jC2Tgk2L/958.jpg (https://postimg.cc/jC2Tgk2L)

[otphas]

Tomorrow will make this test for sure!

[Woxner]

if dev unit is turning then i going with maybe wrong toner. i have seen the numbers look right but toner was the issue. had this before even on smaller machines.

[tsbservice]

if dev unit is turning then i going with maybe wrong toner. i have seen the numbers look right but toner was the issue. had this before even on smaller machines.

Wouldn't that being seen on mag roller?

[Woxner]

Oddly enough it still looked like a good blk. I had inmates put ricoh toner in and the dev unit looked good

[otphas]

Hello,

today we checked dev unit and all seems ok, gears are in good condition and developer roller turning smoothly. We found that charge on the corona grid is not ok, must be 700-800V, ours is around 200V , all cables for high voltage are checked and all is ok with them too. So we think that something is wrong with HV1 board.

[tsbservice]

Hello,

today we checked dev unit and all seems ok, gears are in good condition and developer roller turning smoothly. We found that charge on the corona grid is not ok, must be 700-800V, ours is around 200V , all cables for high voltage are checked and all is ok with them too. So we think that something is wrong with HV1 board.

But you stated Vdc and Vg are looking normal in state confirmation under table 1 and 2...:confused:
What about Vpp reading?

[allan]

Hi guys,

counter is 319K, all parts and toner are OEM and life counter is ok, no one part is over the life. Half tone or 255 doesnt matter, print very light

Something fishy about that demo print. There is only a single tone on there and even where the image of the bird should be there should be some white blotches.
Ouch not liking it. Hope its a HV issue that is messing with the image processing there.

[Toxic]

Yes, that is really strange.
Did you try to stop machine during printing and check image on drum is it also faded same as on paper?

[otphas]

Seems HV1 board is defect, high voltage to charge corona and DV unit is under normal values. Any HV1 for selling?

[elmaligno]

We have a issue with Bzh 958 , print is very very light , values in Level History 1 and 2 is normal. Also coming warning P-9 . Transfer belt and roller seems ok , ID sensor also was cleaned and seems ok. Any tips ?

I would check the operation of the transfer belt sensor. it has failed on occasion and caused me this problem. Replace it.

[allan]

I would check the operation of the transfer belt sensor. it has failed on occasion and caused me this problem. Replace it.

Want to tend to agree. That is complete gradation failure.