I have created my own version of the LAN/VGA module designed for the X3000 series oscilloscopes form Agilent/Keysight. I had one version of the board working perfectly, though it had some mod wires. I did a respin of the board adding tracks to replace the mod wires, but now on power-up I am seeing a message on the screen which says "System concerns detected: LAN/VGA module fault". I don't have a screenshot at the moment, but it's just a very small window that pops up in the middle of the screen.
I know the problem exists on my board. There is absolutely no doubt about that. My question is, what sort of faults cause that error to appear? Shorts? Incorrect power rail voltages? Bad communication? Combination of issues? I am trying to narrow down what is wrong with my board, especially considering I had a similar one working just fine previously. I've checked my components, orientations, values, etc. so at this point I'm trying to narrow down where else the problem may exist.
To be clear, I am NOT asking what might be wrong with my board, and I am not necessarily seeking suggestions. I am simply wondering what triggers that error to appear on the screen of an X3000 scope. Hopefully this is clear.
Thank you very much,
Matt