PanelDue Failure?

  • I included a 4.3" PanelDue with my Duet Wifi order and finally got around to installing the system last week. When I hooked everything up it was operating basically normally except about 1 in 4 times I turned the machine on the screen would flash white and then go dark and stay that way. Over the week of use it has seen so far this problem has gotten worse to the point where it will never display an image (occasionally it will display the home screen for ~1s). The touch controls are still functional when this happens, or at least I can hear the audible feedback from menu selections. The cables and connections all look good, my power supply is stable at 12 volts, and in all other ways the Duet Wifi works perfectly. I have reseated the daughter board on the LCD header and made sure that none of the hardware has cold solder joints, a short, etc. Any ideas or did I just happen to get a dud?


  • administrators

    Most likely the back light inverter on the display panel has an intermittent fault; but there is a possibility that it is the Panel Due controller board that is faulty. If the voltage on the LEDA pin of the display is close to 3.3V then the problem is almost certainly in the display.

  • Yeah, I measure 3.3V on the controller and about 3.0 on the back of the panel where the screen print is labeled LED_A under Backlight Control. So I guess the problem must be the display. Time for an RMA or would a repair be possible? I can't say I am familiar with LCD backlight power circuits, but it can't be too complex.

  • administrators

    It's probably the display, however I suggest you install latest firmware on the PanelDue in case the Gnu C library bug that affects PanelDue firmware 1.14 and earlier is to blame.

  • Will do. Thanks for the quick replies.

  • Had a hell of a time getting bossac.exe on my computer (ended up installing an old version of the arduino IDE) but finally managed to flash the updated firmware to the paneldue. Everything is back to working. I am glad I don't need to replace any hardware.

  • Spoke too soon, I guess it was simply luck that it was working because now it is dark again.

  • administrators

    If you have a multimeter, check the voltage on the LEDA pin. It should be 3.3V if the PanelDue is commanding the backlight on.

    Check that the display voltage selector jumper is fitted, in the 3.3V position.

  • Yeah, jumper is correct and I get the correct voltage on LEDA. A new panel is on the way from Filastruder and so it should be fully functional again shortly.

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