Canon C3525 image issue at top of page only

[tbsl]

Hi

I have a weird problem that has stumped a few engineers here. The image below shows at the top of each page these four marks as highlighted. We have changed drums, fuser, belt, devs but to no avail. Done the maintenance routines etc.
Does anyone have any pointers as to what the problem is please?

Thanks in advance

[Brian8506]

Re: Canon C3525 image issue at top of page only

Small rotational pattern. What about the transfer roller

[tbsl]

Re: Canon C3525 image issue at top of page only

Hi

Thanks for the reply. We actually have just changed the complete right hand side door from another machine but still the same issue. Running out of ideas on this one

[nathicana]

Re: Canon C3525 image issue at top of page only

Hi

Thanks for the reply. We actually have just changed the complete right hand side door from another machine but still the same issue. Running out of ideas on this one

Could someone have loaded paper into the machine that has these marks already on it?

[fchu5959]

Re: Canon C3525 image issue at top of page only

[QUOTE=tbsl;2269315]Hi

I have a weird problem that has stumped a few engineers here. The image below shows at the top of each page these four marks as highlighted. We have changed drums, fuser, belt, devs but to no avail. Done the maintenance routines etc.
Does anyone have any pointers as to what the problem is please?

[Venom]

Re: Canon C3525 image issue at top of page only

Only 2 things can cause dots like that. Contaminated charge roller or a blob of toner on Dev unit mag roller.

[fchu5959]

Re: Canon C3525 image issue at top of page only

Only 2 things can cause dots like that. Contaminated charge roller or a blob of toner on Dev unit mag roller.

I agree with the charge roller but the drums as well as the devs and the fuser have been replaced!!!

How is the paper fed? A4 or A4R?
Does it occur on copy and prints as well?? and from all paper sources??

We need more informations to narrow down the issue.

[Brian8506]

Re: Canon C3525 image issue at top of page only

You said he changed all the drums. Did you change the whole drum units or just the cylinder?

[bobburnsreb]

Re: Canon C3525 image issue at top of page only

[Cause]The image failure occurs when rollers have foreign matters or flaws.[Service work]Check the rollers or gears of a) to m) below.
No interval (xx pitch) Parts Parts No
a 94mm Photosensitive Drum Drum Unit
b 44mm Primary Charging Roller Drum Unit
c 35mm Cleaning Roller Drum Unit
d 792mm ITB (Intermediate Transfer Belt) FL0-0222
e 50mm Primary Transfer Roller FE3-0986
f 46mm Secondary Transfer Inner Roller FL0-0859
g 62mm Secondary transfer outer Roller FE3-4783
h 38mm ROLLER, SECONDARY TRANSFER,FR. FE3-0978
i 31mm / 15.5mm Developing CylinderFM1-B264 (DEVELOPING ASSEMBLY, Y)FM1-B265 (DEVELOPING ASSEMBLY, M)FM1-B266 (DEVELOPING ASSEMBLY, C)FM1-B267 (DEVELOPING ASSEMBLY, BK)
j 57mm ITB Tension Roller FL0-0127
k 76mm Fixing FilmFM1-D280 (120V)FM1-D281 (230V)
l 44mmVertical Path Roller FL0-1834ROLLER, DRIVEN ROLLER FC0-7610
m 2.2mm 36T Gear driving Fixing Pressure Roller FU2-1372

Good Luck!

[nathicana]

Re: Canon C3525 image issue at top of page only

[Cause]The image failure occurs when rollers have foreign matters or flaws.[Service work]Check the rollers or gears of a) to m) below.
No interval (xx pitch) Parts Parts No
a 94mm Photosensitive Drum Drum Unit
b 44mm Primary Charging Roller Drum Unit
c 35mm Cleaning Roller Drum Unit
d 792mm ITB (Intermediate Transfer Belt) FL0-0222
e 50mm Primary Transfer Roller FE3-0986
f 46mm Secondary Transfer Inner Roller FL0-0859
g 62mm Secondary transfer outer Roller FE3-4783
h 38mm ROLLER, SECONDARY TRANSFER,FR. FE3-0978
i 31mm / 15.5mm Developing CylinderFM1-B264 (DEVELOPING ASSEMBLY, Y)FM1-B265 (DEVELOPING ASSEMBLY, M)FM1-B266 (DEVELOPING ASSEMBLY, C)FM1-B267 (DEVELOPING ASSEMBLY, BK)
j 57mm ITB Tension Roller FL0-0127
k 76mm Fixing FilmFM1-D280 (120V)FM1-D281 (230V)
l 44mmVertical Path Roller FL0-1834ROLLER, DRIVEN ROLLER FC0-7610
m 2.2mm 36T Gear driving Fixing Pressure Roller FU2-1372

Good Luck!

Where did you find the repetitive defects guide? I looked in the service manual and troubleshooting guide, must have missed it.