HP 3800n/Canon c1022 Engine problems

NO errors on start up or printing!!!!

The Image prints full color on the band test and this is the image
its the same for all printing.

It was printing full page color and the PQ test printed all the colors fine.
there was a prob with the black slot spring contact ,fixed
did the engineer test , all cymk bands look good but fade 1/2 page

All the l+r slide and cams replaced and carefully reassembled to make sure all contacts are set on the L side HV board
ETB assy makes contact with the 4 drums

all carts good tested with disable cart test

All solenoids were cleaned off with the stickey pads issue

ETB assy is good Belt in good condition 20 k total prints


just for some crazy reason it started to do this

it was printing the full demo page ,but no black until it was fixed

off and on, hard reset, did the manual component test

all works

any help???


Thanks Guys

PUD

 

Do you happen to have a finished print of your sample image without the imaging error for comparison? Also any other printed samples with the error.

if you print solid separations, full coverage prints of CMY and K, what do those appear as? Run several half tone print samples like that (30% C 30%M etc) and post those.

the ITB would be causing a defect throughout all colors. Your yellows appear fine, perhaps black also. Cyan and magenta seem to be the trouble

 

Yes on all questions

START:
It Printed the "demo" perfect except the black was not working
I did the cart change and found out it was the spring HV bent in just enough not to work .

ALL Carts WORK !

It was the BK slot itself so now it prints black.
I fixed all the L & R slots and cams, removes all solenoid pads to stop the sticking issue , "dont care about click sound.
Did the color Bar test and was great except the black,
*****I know the ETB belt is good and one BIG question is the Spring loaded cam inside where the sticking solenoid was to clean it off too,
I was trying all sorts of that Spring cam positions to put the main roller assy to engage the rollers to the drums, 1 for the BK and 3 for the CYM

Made no difference, Same print w /3" cut off

All the rollers are engaged when printing color I see that with door open and switch blocked closed.
I know they work and can see the calibration squares pass when in calibration mode.
I pulled the L side HV board to make sure all the contacts were clean, VERY clean like new!
Did all the Manual checks, even in Service mode.
CK all Connectors and the Right side Drum drive gear assy
The leading edge sensor has to be good, registration top margin page down exact every time.
Fuser roller is good.
The front door closes very nice and aligned .

"Engine Test" perfect CYMK sm Lines about 1/2 way down page then fades off

this will go thru full calibration with no errors at all on start up,
it does the same thing when printing from PC

So it will print about 3" in full color"DEMO" the as if the rollers were removed during the print cycle
It will do the same for the color bar test with the black boarder lines to the 3" ,No paper stoppage
It passes smooth thru.

Again no sensor error I can see ,It acts as if there is no error
cant be the belt
I can see the ETB rollers on the all Drums when printing
Its dim light near this printer .


Its as if it just the image just stops like the HV just turns off as if it was finished printing


Hope this helps,
We really need this printer ,cannot leave our home and I have it all back together

This is gonna be so simple..... I missed something or it just died, but NO Errors on screen ,SVC


I try to give as much info techs like to see like I would like to see myself

Thanks for the response

PUD

 

found out the problem,It was not shown in the Svc Man I had
the drive gear assy was out of sync with the gear assy on the frame, very easy to move.
Once that was done it printed , then you must calibrate 4X in a row to get the formatter totally cleared and calibrated.
The HP Techs were great to work with
Here is the Service PDF with this hard to get info See attached