HP DJ t790 requires to remove paper when no paper

[albardnew]

When load a roll of paper, T790 displays a message "remove paper from sheet feed" and highlights the icon of the sensor of the Sheet of paper which is located on the right hand support of a roll (when there is no sheet). In case of sensors' diagnostics T790 requires to remove paper from a way of sheet feed when there is no sheet. All previous steps of diagnostics pass normally: front cover sensor, lever sensor and out of paper sensor. Replacing of the sensor doesn't bring result. The cable is checked to the connector on EE-BOX board, it is operational. On the sensor' LED  is DC2.5V; on a photocell collector 3.3V, on the emitter 2.5V irrespective of existence of a barrier (measured by oscilloscope). In case of the removed sensor the same. Is it failure of the controller on a board of PCB05 EE-BOX or on a board of the formatter?
IMPORTANT: malfunction take place on two same plotters...

[Mikeg81]

Hi,

You need to clean the sensor

Then, do the sheet sensor calibration. Try it a few times

[albardnew]

Hi, Mike!

I did this procedure many times whith both of a new and an old sensors, but unsucsessful.
Replacing of PCB05 and total calibrarting solved the problem.

Thanks for your help!
Best regards.

Alex K.

[kusanjiv]

　

　

　

　

If the jam occurs with roll or single sheet, check with the customer that the output tray is closed. The printer does not allow printing or loading roll or single sheet with the Output Tray open (a message appears on the Front Panel). However if this is the case it is likely that the Output Tray Sensor is broken. Ask the customer to run the Output Tray Sensor diagnostics (see 4.6 Output Tray Sensor on page 191). If the diagnostics fail, arrange a service engineer visit to replace the Output Tray Sensor (see Output Tray Sensor Assembly on page 395).

If the jam occurs with roll, and the output tray is closed, check with the customer whether the jam occurs at the beginning of the print, because due to the paper curling the paper is stopped into the Output Tray (does not fall into the basket), provoking a paper jam. If this is the case, check with the customer whether the ribs in the Output Tray have risen or not. If these ribs are not up while printing from roll, it can cause paper jams at the beginning of the plot. If this is the case, arrange a service engineer visit to replace the Output Tray.

If the problem persists it is probably a mechanical problem that should be diagnosed by a service engineer. Arrange a service engineer visit to diagnose the issue.

　

　

The service engineer should first follow the paper troubleshooting in the user's guide, and also the instructions in this manual given to the customer by the call agent, to double-check that the troubleshooting has been done correctly. In most cases the problem can be solved by following these instructions. However, if the problem persists, remove the covers and try the following steps:

　

Check that all the Pinchwheels are all present and well assembled; check also that all the pinchwheel springs are in place.

Check that the starwheel rail is correct.

Check that

　

　

　

　

　

　

the spindle is not broken or inserted incorrectly, and that the spindle gear is OK.

[albardnew]

To kusanjiv:

Thank you for your attempt to help me.

Тhe problem has no relation to a paper jam.
If you attentively read my first message, then would understand it directly.

Тhe problem is fixed by me independently, I reported about it earlier.

[israel1973]

hi from mexico , I solved the problem by giving a File System Check, In the Diagnostics menu, select File System Check and press on this menu option, the Touch Control Panel asks you if you want to proceed with the File System Check