Antwoord op "Half of the string of LED Christmas lights doesn't light up."I crawled on the roof, freezing my arse off, and found the last bulb that was still lit. I put a replacement bulb in it to ensure the new bulb worked before I went bulb-by-bulb on the bad ones. MORE lights went out, and I couldn't get them to come back on, even with the known good bulb back in. SO, since i had an extra length of lights at the end of the run, I just pulled the dead light section aside and rehung the line starting at the lit section. When i take them down this year, I'll troubleshoot them in the warm garage!