DF790 with 6550ci error 6110

[Tricky]

Hi

I have a problem with a DF 790 finisher.

I can only do one copy to the middle finisher tray because after the copy is delivered the machine indicates a jam although there is none. Paper gets sent to the top and bottom (stapling tray) as normal and I can do multiple copies using these trays

Opening and closing the finisher door clears the error.

The top tray uses a different paper path so I ignored that but the finisher entry for trays 2 and three is the same but the machine gives a 6110 error when using the middle tray only.

There only seems to be two sensors in the paper path for the middletray the entry one which is optical and the exit one which I have added another wrap on the spring.

Why would the sensor give an error when using one paper path (the simpler one of the two) as opposed to another more complex path that works ok?

Firmware is the latest.

6110 - DF paper entry sensor (DFPES) is not turned off
within specified time of its turning on

[blackcat4866]

Re: DF790 with 6550ci error 6110

The way I see it you've got quite a few possible failure areas:

1) DFPES reflective sensor or it's reflector is dirty
2) DF feedshift gate 3 is broken, or not moving at the right time, or slow, or obstructed
3) DFFSSOL (DF feedshift solenoid 3) is not moving at the right time, or magnetized
4) DFEM (DF eject motor) drive failure
5) DFSES (DF sub eject sensor) is blocked, dirty, flag broken, sensor failed, etc., etc.

I'd start by looking into those possibilities. A simple place to start is to go to sim U241 and check that you can change the state of sensors DFPES (displays as HP) and DFSES (displays as Sub Tray Eject). You can also test DFEM in sim U240 (displays as Eject(H) and Eject(L)). It's fully possible that paper exiting to the elevator tray ignores DFPES. Just because the diagnostics point to one specific sensor does not mean that there isn't another sensor involved in the decision making process of calling that jam.

Additionally, the machine diagnostics are not the final word on whether a sensor is good or not. The only definitive test to to put your meter on the output lead of the sensor (whether it's at the sensor itself, somewhere in the harness, or at the controller board) and watch the values as it changes state. I usually go to the controller since it's centrally located, and all the sensors eventually get there. Typically the controller is looking for a threshold of around 3.7vdc to decide whether the value is low (<3.7vdc) or high (>3.7vdc). If your output values are hovering around 3.7 it's a crapshoot whether the controller will decide if it's high or low.

The output lead is typically the center lead of the sensor, read against the 0vdc ground. At the controller you're looking for:
DFPES: YC21-9
DFSES: YC21-3
page 2-1-3 of the DF790 service manual
It's all in the manual for you.

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