E-Studio 3511 - CF20 sensor problem

[Mallorychan]

Hiya,

I'm after a little advice with my 3511.
The black copying/printing is working just fine but any colour copying results in the paper stopping before it hits the drum and a 'call for service' error.
The error is a CF20 code and i've had all the colour cartridges and developer units out and they're ok, all the magnetics are working properly and i'm fairly sure the problem is the colour auto toner sensor (which i have cleaned but the code still arrives).

The solenoid is working fine (using start-03-125-start-175-start process) but the sensor LED test (126-start-176-start) reveals nothing. Where is the LED that is supposed to light up? Is it in the sensor window or is it located elsewhere?
I just want to confirm it's the sensor that is gone before we shell out for a new one

Many thanks,

Mal.

[Baphomet]

I believe the LED is on the sensor itself. Anyway, I think that you might save yourself some grief if you consider the movement of the revolver unit. Does it exhibit backlash, hesitation, or does it feel rough?

Inspect the gear on the revolver unit for broken/missing teeth.
Check that the revolver motor is mounted correctly.
Check for backlash ... here a link that will provide you some info on that:
Technet Article

One word of caution on working in that sensor area, the shutter the solenoid moves in and out of position has a gray colored reference plate which sometimes gets dirty (although the code is usually CF30 or 40). If you clean that plate ONLY USE AIR. You can ruin that plate by simply touching it.

Hope this info helps, good luck.

[Mallorychan]

Thank you for the reply Baphomet and thanks for the link.

There was a bit of play in the revolver unit but i've fixed that, unfortunatly i'm still getting the same CF20 problem.
I've checked all the drive teeth, cleaned the ones that were a little grimy and generally made sure the revolver is fit and fine.
I've dismantled the sensor and am still getting no responce from a call for the LED to light and no responce from a 441 code either so i'm going to have to surmise that it's the sensor that is faulty.

Thanks for you help.

Mal.

[mckinley]

what colour were the teeth on the revolver motor gear? they used to be a gold colour, but they have been changed to a dark grey, if it's got a gear with the old type colour then the chances are that your revolver motor has failed. it's very common for the motor to fail on these machines, causing CF20.
another cause of CF20 is if the colour dev is shot.

[Mallorychan]

Yeah, it's the older gold tooth type but it seems to be working just fine.
The motor turns the revolver unit for replacing toners, auto-calibration and other such tasks and the revolver unit spins at start-up as it's supposed to.
There is no play or back-lash from the revolver now, all the teeth are clean and unworn and it moves smoothly if a little stiff when pushed around.
All the colour developer units seems to be fine, they turn well and the toner is raised by the magnetics in an even distribution across the rollers.

What happens is this - after i send a colour print from the pc, the 3511 powers up, the transfer belt turns into position, the paper is picked up from the draw and starts it's journey and then when the colour auto toner sensor solinoid fires and the sensor is released past the creaning brush the machine stops and the call service error is shown. The paper does not jam and is easily retrieved from the rollers.

Can anyone shed anymore light on this?
Again, many thanks for the help folks

Mal.

[Mr Spock]

Have you run 05-207 and 208? If these fail then it is either the gray patch or the sensor itself. It could also be the developer material (check the life counters). Also clean the sensor under the transfer belt by the fuser side of the machine. This reads how much was transferred and could be dirty causing the error.

[Mallorychan]

Hi Spock, Thanks for the advice

Tried running 207 & 208 (using method 5 from the manual, i'm assuming here though as neither code are in my service manual - what are these codes please?) and both fail the test print on colour with the CF20 error as before.

The machine has only done 6700 colour prints so i'm pretty sure it's not the dev. material.
I'll give the sensor a clean this evening and let you know if it helps.

btw, what is the 'gray patch' you mentioned? (probably just being think here).

[Mr Spock]

If 05-207 and 208 do not work then you will need either the sensor or the gray patch. On the sensor is a black "hood" inside of this is a gray patch. DO NOT clean this with anything but air!!!!!!! If this is not completely solid then that is the issue. If this is solid then I would suggest the sensor first. These codes check the light reflecting off of this patch and back to the sensor. If this is not within a certain range then it codes out.

[Mallorychan]

Hi,

Back again for more advice i'm afraid.

Mr. Spock, the sensor you're talking about with the gray patch - is it the colour auto-toner sensor or the Image quality sensor (located under the transfer belt unit)? Sorry to ask this but i'm getting myself a little confused.

If it's the latter then someone may be able to help with a secondary problem, that is i can't get the bloody transfer belt unit out!! I've been fighting it for 2 days now with growing frustration. I've followed the removal instructions from the manual to the letter but the unit will only release and lift up on the front side, the rear side seems to be fixed and will not release!? is the manual wrong? are there gear i need to be shifting? have i missed a fixing/screw? I'm using as much force as i dare without breaking/warping the unit and for the life of me cannot find where it's attached the back plate. I've removed every screw i can get to and removed the drum and revolver units to get a better look but still cannot see where it's attached

Any help here would be really appreciated.

Mal

[Baphomet]

CF20 is the auto color toner sensor which is located above and to the left of the revolver. CE20 is the IQ sensor which is to the right of the transfer belt assembly. As for the transfer belt assembly, there are two bolts that run the entire width of the transfer belt and fasten the backside. It sounds like they have not been loosened. They are VERY recessed and easy to miss (most people miss tightening them again after they reinstalled the t-belt assemb). One is sort of to the upper left of the three wires you disconnect from the front of the t-belt (about two inches to the upper-left). The other is to the right of the first by about 6 inches. They are deeply recessed and when you look in the recess you will see that they have a cross-head tip which will accommodate either a slotted or cross-point screwdriver. Also, be sure to completely remove the drum unit and then the t-belt cleaning blade assembly (book says to just set the t-belt cleaning blade assembly off to the side, but it is better to just remove it). Only other thing that could hold the backside down would be the locking lever on the rear side. If you are looking at the t-belt assembly you will see a metal bar at its highest point extending from the front to the back. You probably removed the clamp which hooks on the front side of this bar already, but if you follow the bar to the rear you will see where there is a lever which has a little metal knob on it. You can pull that little knob slightly toward you and rotate the lever clockwise about a quarter of a turn to release the bar on the backside.

Hope all this helps.