- Dec 7, 2017
So I have this Christmas tree with 2 light strings permanently attached to it. What happened was that one by one a few lights failed in short order, and then one whole string went out. I continuity checked them all and all but 2 (out of about 60 or so) were burned out, with burn marks on the interior. What I need to know is if this could have been caused by a power surge or if it is the string itself that is faulty, because I don't want to buy new bulbs only to have this happen again.