I have the "faulty" ceiling LED lights also in my 2015 PC. One failed completely, and three others have failed on one half. The first two failures were within the warrantee period and Phoenix sent replacements. I have not bothered to deal with the other partial failures, because I rarely use the ceiling lights...mostly when cleaning and packing/unpacking between trips. Ironically one of the reasons I rarely use them is that they are way too bright for ambient lighting use, so having only half the amount of light is actually an improvement. When I want evening ambient light, I have been using the four "reading" LED lights, one in each corner of my living space. If I lived in my PC for all or part of the year, I would pursue a more elegant solution...but since my use is for weekend sports trips, it hasn't been important enough to make it to the top of my to-do list.
Ann