I have a SOPINE module on the Model A baseboard, with the 7 inch touchscreen kit installed. However, when I try to boot an OS from the SD card, neither the touchscreen nor the HDMI port output anything (my monitor doesn’t even detect the connection). I have tried imaging the card with dd, vanilla etcher, and the Pine64 installer. Nothing has worked. The power lights on both the board and the module light up, and the processor gets somewhat warm to the touch, but not hot or even that warm, so I suspect that it’s just not booting.

What are the steps for diagnosing a situation like this? I’m starting to worry that I got a defective part.