If you have issues with a string more times than not its the last working pixel that has failed as a common falure mode is the data output of the chip that fails and thus doenst send any data. I always change 2 pixels, the first one not working and the one before it.
Agree.. I always change two of them out. If you notice in the picture its the + and - that has shorted and cause the fuse to blow on the j1sys card. Never seen this one before today.