[CQ] C350 Odd behaviour

[mrwho]

Good morning, guys.

I'm here with this dinossaur which is doing something I've never seen any of these machines doing. If I try to print out several copies in a row of the 8-color gradation test, the first page comes out okay and then the subsequent pages come with lines on the prints and with the color registration completely off, but unconsistently (meaning the colors could be off by 1mm at the lead edge and by 3mm near the rear edge, for example).

I've already swapped several parts with a dismantled machine (known to be working before being teared appart), but no luck so far:

- IU and Developing motors
- Transfer belt
- Swapped the transfer belt motor with the fusing motor
- Control boards (the two in the metal cage at the back).

I'm out of ideas. Anyone had one of these?

PS: Sorry for the bad quality picture, I didn't have a working scanner handy.

[blaze2000]

Re: C350 Odd behaviour

Really strange, so what happens if you run some halftones from test mode? Just like at 175 and run just one color at a time. Have you tried replacing the HV1, I seen some really strange issues by cured by the hv1.

[Darren King]

Re: C350 Odd behaviour

Looking at the picture it appears that the problem is occuring in the cyan and magenta only. Maybe IU problems?
Darren

[mrwho]

Re: C350 Odd behaviour

Looking at the picture it appears that the problem is occuring in the cyan and magenta only. Maybe IU problems?
Darren

Although I didn't mention it, my colleague who also tried to fix this tried at least with the Magenta unit, without results. It also happens on yellow, although you can hardly see it, unless you look at a composite color (that's why I marked the green gradient).

I'll try another HV1 as per Blaze2000 suggestion and see what happens. Thanks!

[Albonline]

Re: C350 Odd behaviour

Although I didn't mention it, my colleague who also tried to fix this tried at least with the Magenta unit, without results. It also happens on yellow, although you can hardly see it, unless you look at a composite color (that's why I marked the green gradient).

I'll try another HV1 as per Blaze2000 suggestion and see what happens. Thanks!

also try grounds on the led rack. the bushings/ground path in the 2nd transfer unit will cause this also.

[Albonline]

Re: C350 Odd behaviour

one other outside possibility is the fuser unit itself loading the drive system

[EarthKmTech]

Re: C350 Odd behaviour

make sure the fusing loop sensor is clean and moving without restriction.

a jamming/dirty fusing loop sensor results in the fuser running faster than the belt continuously - long sheets end up tugging on the belt causing colour registration issues.

this applies to every machine thats an ongoing development of the cf2001, ie, all the way upto c754.

[JustManuals]

Re: C350 Odd behaviour

If you need the service manual, let me know and I'll forward it to you.

Paul

[mrwho]

Re: C350 Odd behaviour

If you need the service manual, let me know and I'll forward it to you.

Paul

Thank you, Paul. I'm already equipped with all the necessary documentation.

I'll forward all the suggestions here to my colleague now dealing with the beast.

Thank you all!

[mrwho]

Re: C350 Odd behaviour

make sure the fusing loop sensor is clean and moving without restriction.

a jamming/dirty fusing loop sensor results in the fuser running faster than the belt continuously - long sheets end up tugging on the belt causing colour registration issues.

this applies to every machine thats an ongoing development of the cf2001, ie, all the way upto c754.

Thank you! That seemed to have solved the problem - the actuator spring was out of place, something hard to see if you're not looking for it.

Reps to you! Thanks again!

[EarthKmTech]

Re: C350 Odd behaviour

Thank you! That seemed to have solved the problem - the actuator spring was out of place, something hard to see if you're not looking for it.

Reps to you! Thanks again!

That sensor still catches people out today on the current machines and its most amusing to suggest it AFTER they have replaced half the machine trying to work out the problem