Overall density is low, white spots on solid pattern - Pro 951

[Takhnamishvili]

Re: Overall density is low, white spots on solid pattern - Pro 951

Hello guys again! Today I borrowed Dev. unit (of course developer too) from good working machine, after installing it on problematic machine, I tried to print 100% coverage from service mode, it printed perfectly, but showed error code C2412 and it's clear why, after auto maximum density adjustment, I retried to print 100% coverage and density became lower and engine showed same error code. Definitely Developer is faulty there, but I'm little afraid, what if after replacing developer and dev. unit with new ones, making toner density sensor initial adjustment, density will become low? I'm asking because it's fact that density is very low and machine recognizes it as normal :||

P.S. Before installing borrowed dev. unit, I tried dipswitch 6-7=1, it gave nothing.

[louis.robins]

Re: Overall density is low, white spots on solid pattern - Pro 951

I think the cause was poor paper quality.
You need to do the recommended maintenance as described in the manual?

[WLIT]

Re: Overall density is low, white spots on solid pattern - Pro 951

I've seen this before and just replacing the developer in the developing assembly should get you back to normal as you have proven already. If you are not aware, the 951 will not shut down or stop when toner is allowed to be run out. I would reiterate this to your client as I had a client who would not pay attention to the toner level indicator in the panel. It took 2 bags of developer, only lasting around 5-600K each, before I could get my client to add a new bottle as soon as the indicator turned red. Now they are getting an easy million clicks before developer gives up. My scenario was primarily due to the Pro being a new unit and learning curve. Best of luck if you haven't fixed already.

[allan]

Re: Overall density is low, white spots on solid pattern - Pro 951

Hello guys again! Today I borrowed Dev. unit (of course developer too) from good working machine, after installing it on problematic machine, I tried to print 100% coverage from service mode, it printed perfectly, but showed error code C2412 and it's clear why, after auto maximum density adjustment, I retried to print 100% coverage and density became lower and engine showed same error code. Definitely Developer is faulty there, but I'm little afraid, what if after replacing developer and dev. unit with new ones, making toner density sensor initial adjustment, density will become low? I'm asking because it's fact that density is very low and machine recognizes it as normal :||

P.S. Before installing borrowed dev. unit, I tried dipswitch 6-7=1, it gave nothing.

Keep in mind that doing those switches would take up a 1000 prints before the change would be reflected. And the change in toner concentration is very small.
Would think that you got a humidity issue there? Some moisture in the developer...
In that case the issue should return in time.

If you are a cowboy you can add a tablespoon of toner in there and run dev init again.
Don't blame me if this don't work. Been taking developer way past life with this trick but not recommended where good quality is needed.
Before you know it you could have a nice coating of toner everywhere around the imaging section.
The new concentration includes toner, paper dust, common dust, and human skin cells.

[tsbservice]

Re: Overall density is low, white spots on solid pattern - Pro 951

Keep in mind that doing those switches would take up a 1000 prints before the change would be reflected. And the change in toner concentration is very small.
Would think that you got a humidity issue there? Some moisture in the developer...
In that case the issue should return in time.

If you are a cowboy you can add a tablespoon of toner in there and run dev init again.
Don't blame me if this don't work. Been taking developer way past life with this trick but not recommended where good quality is needed.
Before you know it you could have a nice coating of toner everywhere around the imaging section.
The new concentration includes toner, paper dust, common dust, and human skin cells.

Hey allan, sounds you are influenced by your neighborhood. I like your voodoo mixtures.

Regards: YouTube

[allan]

Re: Overall density is low, white spots on solid pattern - Pro 951

Hey allan, sounds you are influenced by your neighborhood. I like your voodoo mixtures.

Regards: YouTube

Side tracking a bit here.
Back at you: YouTube
If i only had an LTD like that...
I roll with the Spirit

[tsbservice]

Re: Overall density is low, white spots on solid pattern - Pro 951

Side tracking a bit here.

Yes, we are going a bit or two offtopic here...but hey it's that corona vileness everywhere, so hopefully we may be excused.

Back at you: YouTube

Thank You for that! Very impressive!

[Takhnamishvili]

Re: Overall density is low, white spots on solid pattern - Pro 951

Keep in mind that doing those switches would take up a 1000 prints before the change would be reflected. And the change in toner concentration is very small.
Would think that you got a humidity issue there? Some moisture in the developer...
In that case the issue should return in time.

If you are a cowboy you can add a tablespoon of toner in there and run dev init again.
Don't blame me if this don't work. Been taking developer way past life with this trick but not recommended where good quality is needed.
Before you know it you could have a nice coating of toner everywhere around the imaging section.
The new concentration includes toner, paper dust, common dust, and human skin cells.

Thank you for your suggestions! I really did not know that this dipswitch gives effect after 1000 prints. I will try your ideas, as soon as coronavirus leave us alive

[allan]

Re: Overall density is low, white spots on solid pattern - Pro 951

Let me correct myself.
To get the prints darker sould not take too long as it needs to add toner.
Reducing the density would take that long.

Did you add a small amount of toner and the ran dev init?
You can always add but if you dose in with too much toner is would fog up the machine or give you nasty background.

[Takhnamishvili]

Re: Overall density is low, white spots on solid pattern - Pro 951

Hello guys, I returned to work after long time due to pandemic.

So today I turned off Drum Potential Sensor with dipswitch, tried to print a number of sheets and density started becoming higher, after 30 pages it became excellent. So as it seems DPS is dead there and I'm going to change it with new one.

Thank you all for your suggestions and attention!

[Pavel]

Hello, I can bring up this topic again?
I have 1 to 1 same problem like topic starter.
DPS sensor output signal is jumping 0-64-256-0- ...
DIPSW 6 7 to 1 did not help. Now i use only one solution - time to time add toner inside developer unit.
What am I doing wrong?