Just received this display and it seems to almost always halt somewhere during the power up phase. I was able to get it to display the computer's output once, after unplugging everything and re-seating all of the connections, but as soon as I unplugged and re-plugged in the power to the display again, it went back to its initial behavior.
Except for the one time I mentioned above, when I plug power into the main board, the keypad's light will glow a dull green (but not as bright as it did the one time it worked) but the backlight for the display never comes on. Pressing the power button on the keypad does nothing (I did test that the one time the display did work, and pressing it would turn the display (and the led) off and then both back on again, so I know that pressing it should elicit some change in behavior)
I have tried reseating the cables multiple additional times with no change.
I have tried three different power supplies -- a 12v 3A that I had unused, one of your 12v 1A (part 798) supplies I borrowed from another project of mine, and a variable bench power supply set to 12v (which happened to be the one connected the one time it worked). When the board doesn't work, the bench power supply tells me that the device is drawing a steady 0.02A -- I didn't think to note what it was pulling the one time it did work, but I recall it fluctuating a little and being higher.
I have tried multiple HDMI cables (that work with other computers and monitors).
I have tried two different Raspberry Pi models that work fine with other displays attached (with and without the `config.txt` changes specified for 1694 in the HDMI guide in your learning guides)
If I've missed anything that you need or that I should try, please let me know because I would like to get this fixed or replaced since from what I can tell, it seems to be a defective unit.
Thank you for your time.