Thank you! It seemed to help here as well. I don’t have a sdcard in my zero w at the moment but at least I was able to turn on the GRPS shield. From what I can tell this must be a manufacturing error?
Like jaanus I would love to know if it’s possible to turn it on without actually pressing the button. For my project this will be placed at a location not available to me at all times so being able to reset it by plugging power in/out is essential.