IR7105 Dark Patches when Test PG

[sunboi]

Hi Guys,

Would appreciate any kind advise from the experts here as i really tried and run out of ideas. Please note that i am not a authorized tech from canon thus please be patience with me. You guys will save me a lot of time trying to figure out whats wrong and I get completely obsessed if it cannot be fixed.

I recently bought the Ir7105 from an exporter for my printing biz. When i did a test print at the supplier's office, everything was okay.

When its back in the office and i have not even change the normal parts which i normally do so and i did a Test PG. It came out. Totally black with the normal grid lines. total black.jpg

I used to have this issue when my laser shutter was damage but when i peek into it, it has red line so i assume its not damage. Next, I change all wires(primary, secondary, Pre-transfer corona) but the problem still persist.

One of my close associates told me that there might be an issue with the potential measuring PCB. But when i checked, the machine did not have one which all of our friends told me its impossible. See attached pic. or is this not where a potential measuring PCB is
Photo 18-11-14 3 15 13 pm.jpg


Anyhow, after scratching head for a long long time, I finally found that i can off the potential measuring in service>copier>option>body>PO-Cnt

After I change this from default 1 to 0. Wohoo, the total black was gone! However!!!!! it came out with this issue.

dark background.jpg
dark patches at the top part from printing & copying!!!

Please! i really run out of idea and i really need to get this machine up!!! Any kind advise would be very much appreciated and I will constantly updates on the changes i did.

[mramlawi]

Re: IR7105 Dark Patches when Test PG

Hi,

first of all enter the service mode and make a p print ,then make clear dc after that returend the factory values which located on the front door inner.
ps:have u change the primary corona ? Some time it need adjustment cos this issue also try to loose the plastic screw in the primary and let the wire rise up on the grid ur problem will solve .

[sunboi]

Re: IR7105 Dark Patches when Test PG

Hi,

first of all enter the service mode and make a p print ,then make clear dc after that returend the factory values which located on the front door inner.
ps:have u change the primary corona ? Some time it need adjustment cos this issue also try to loose the plastic screw in the primary and let the wire rise up on the grid ur problem will solve .

Hi meanlawi,

thank you for the prompt reply. May I check where to get the P print. To be frank, after my canon tech friend advise... I had clear the dc con... And enter the value from the inner door. But the problem still persist.

For the adjustment of the corona wire, I will do that first thing in the morning and update in this forum.

any more advise from any kind profs here?

[sunboi]

Re: IR7105 Dark Patches when Test PG

My concern is right now why did when I did the test print at the supplier's office was perfect but when it got back to my office it's appear the first black printout which I had attached? Could it be something that is experiencing bad connection between the moval?

[sunboi]

Re: IR7105 Dark Patches when Test PG

Any advise?

[sunboi]

Re: IR7105 Dark Patches when Test PG

Hi All,

for the benefit of others who come to search for any resolution.

After i change the HVT PCB Board, Everything is back to normal! Cheers

[JPiek]

Re: IR7105 Dark Patches when Test PG

So the move was probably to bumpy for the PCB ?

[Canuck]

Re: IR7105 Dark Patches when Test PG

If it returns....

[sunboi]

Re: IR7105 Dark Patches when Test PG

So the move was probably to bumpy for the PCB ?

Most likely or it might already been faulty. Lesson learn. Change parts by parts in order not to confuse own self =)

[sunboi]

Re: IR7105 Dark Patches when Test PG

If it returns....

i am not sure if this applies to me as these are used machine from other countries. Till date, i own 5 Ir 7105. Frankly speaking, learnt a lot thru this forum. Anyway, Thanks for the heads up.

[Canuck]

Re: IR7105 Dark Patches when Test PG

FYI...Bulletin is not just for my country...no such thing as a Canadian Canon. Canon Canada distributed the bulletin....models for other countries have same issue.

[sunboi]

Re: IR7105 Dark Patches when Test PG

FYI...Bulletin is not just for my country...no such thing as a Canadian Canon. Canon Canada distributed the bulletin....models for other countries have same issue.

Thanks Canuck for the advise. I totally agree with you as I also learnt from bulletin posted in this forum that fixing assembly can also caused error code 0069. (Which I encounter today!)

I will check on my machine if there are any green dot but I believe it should being replaced by the previous owner as I mentioned in my previous post that all of my machines are refurb machine, so they had been used for quite some time before it reach my hand.

cheers!!

[sunboi]

Re: IR7105 Dark Patches when Test PG

hi Guys,

Same machine is facing some issue again.

After i took out the primary charging, developer, drum to clean & polish, when the print out is dirty but it was not the process unit issue. It was due to dirty upper roller cause the web cant turn. i fixed the issue but when i assemble all back again. the print out became faint on the top part. i suspect something is wrong with the primary charging, but i made several adjustment to the HVSP, GRID, to no avail. It happened immediately after i did a test print after i clean them....

faint.jpg

Any kind tech can advise on this issue???

[sunboi]

Re: IR7105 Dark Patches when Test PG

here are my reading from HV-STS when i am printing
Photo 29-11-14 9 18 17 pm.jpg

My DPOT which i notice that the VDM is lower than the recommended 390 - 450 in the SM . might be this issue?

Photo 29-11-14 9 18 35 pm.jpg

[sunboi]

Re: IR7105 Dark Patches when Test PG

today i tested before doing anything, it printed blank page. Any suggestion?