BHC6500 sc code c4721 APC fail

[Desert Rat]

I called Hytec on this, their tech said it is referring to the black laser unit.
I pulled the black laser thinking it over heated. But no it codes out
with in a minute of power on.
I reseated the connectors a couple of times and dusted off the laser unit.
The lasers for the colors are also dusty but working.
Hytec said it is either the laser or the Image Processing bd.

I need to know what others have done to fix this problem.
And how much trouble it is to change the Image processing bd?

Thanks

DR

[Tech Helpdesk]

Sounds like your black laser has gone down.

[Desert Rat]

Yes, I already know that. According to the book it is missing 12vdc from somewhere.
Is that 12v always present at the laser connector even when it codes out?
I am looking at diagrams today.
Any know where I can get a black laser for this machine?

DR

[RAI]

It's usually not boards that fail. I've had a couple of bad color units I've replaced in the last few years.

[Desert Rat]

Rai,
I'm hoping it's the laser.
My customer is an indepedent quick printer. Notoriously frugal.
He may not want to purchase the laser just to see if that's the problem.
If it is the board I may have a problem with the price or the installation

Stuck between a rock and a hard place again. Damn

DR

[Desert Rat]

My customer bought a black laser unit and today I installed it. The C4721 code has not re-appeared.
Instead it gave me a C4520 clr registration error.
I went into service to run the auto clr regist. program and it coded out with C4503.
Power cycle to clear code and try again, next code was C4502. Cycle the power and give it
another shot got a code C4501.

These last three code all read the same except they refer to the color lasers.

Defined-- when laser correction motor on laser correction sensor was turned off.

Pulled all the lasers out and clean the very dusty laser cavity. Try again and it is stuck on
C4501 for the yellow laser.

The choices the trouble shooting gives me is PRCB, laser motor or sensor.
Now what? I'm thinking the PRCB may have to be replaced.

How much trouble is that going to be for an indy without firmware?
This board is serialized correct?

Any suggestions?

Thanks

DR

[Desert Rat]

Had to try it again now it giving me the C4503 code Cyan laser motor or sensor???
Tried to recall standard data at the factory level and no go.
still C4503 when running the auto clr regist. program
and C4520 in copy mode.

DR

[Desert Rat]

This problem has got my head spinning. Here's what I've done: Customer bought a black laser and I installed it. The SC4721 has not come back
sense. I did the LD bias adjustment in the book, ran auto gamma, drum potential sensor and then auto clr registration. Back to the 4503,02,01 codes.
Ran the manual clr registration. It gave me an ERROR 1 chart not detected. Ran the recall scanner standard data to the factory level.
Also ran recall standard data for the printer to the factory level.

Ran test prints #11 beam check, the color in the squares did not look right. It looked dark.
#53 overall half tone at density 70 and 255 looked ok.
#80 print characteristic evaluation, this print actually looks good no sign of mis-registration color wise. And it looked square on the 17" page.
#54 gradation evaluation pattern, the colors on the lower half of a 17" print looked very lite and faded. And the yellow bar was half off the
page. There was a larger margin on the left side.

I adjusted the printer gamma sensor offset and that brought the lower half of #54 up but still the yellow is half off the page.
Now when I run the manual clr registration adjust it gives an ERROR 5. And some of the readings had N/G next to them.
I will work on posting the samples and I may have a screen shot of the ERROR 5.

This machine needs a tune up. The drums are at 200% plus, the developers are at 115% plus and the transfer belt looks worn. There is a piece
along the front edge that is loose. This piece is 3-4 inches long. And the belt is about to track over the gear in the front.
The customer, because of test print #80 has a hard time believing the transfer belt is at fault. I kinda do too.
It registers the cmy to the black. How can I get the black back to where it should be?
I wonder if I slip a belt from an old C500 on the transfer assembly if that would work? I need to change something in there to
strike a nerve. Come to think of it, after it errors out with the 4503,02,01 codes I do not remember seeing the hash marks it
creates for the adjustment. If the colors key off the black laser and its off by an inch and half, then the sensors would not see
the marks. I will make a point to look for the hash marks next trip out.
I did remove the sensor assemble from the left side and cleaned all the sensors, even under the
lens for the Registrations sensors. And replaced one of the shutter springs.

I try to be through, did I miss something right in front of me.

Thanks

DR

[Desert Rat]

Here are some samples. I will see this machine today.
20150821_182100.jpg20150821_181921.jpg20150821_182138.jpg20150820_001648.jpg20150821_182009.jpgHere are some samples. Let me know what you think.

Thanks

DR

[tulintron]

Here are some samples. I will see this machine today.
20150821_182100.jpg20150821_181921.jpg20150821_182138.jpg20150820_001648.jpg20150821_182009.jpgHere are some samples. Let me know what you think.

Thanks

DR

you believe would be the belt?

I try to calibrate sensors registration PS8 and PS9.


I believe that this error linked the exchange laser.


perform whole procedure again.

Performed recall standard data in Printer Adjustment?