I have a 2011 Corolla, which is paid for, and when I got into vehicle and turned ignition, I heard a pop sound, radio went out for couple seconds, came back on, but now I do not have dashlights. I have head and tail lights. Radio works as does back light of radio, but when I put on headlights, the back light of radio goes out. My mechanic can't figure it out and says it's NOT the fuses; they are all fine. Does someone know what this is happening and how I can be able to see my dashboard at night? thank you!