I literally just had this problem. Was sitting in the Walmart parking lot, taking off the lens so I could take out and replace the bulb. Bulb looked fine. Popped it in the passenger side and it worked, so I knew it wasn't the bulb. Jiggling the switch made it light up, but not stay on. Wound up unscrewing and pulling the whole assembly out (still in the parking lot), unplugging and reconnecting the cables, and finally swapping the switches. Figured the driver side was more important than the passenger side (at least for me). After all that, both sides appear to be working just fine. May have been a loose connection, or maybe the switches are happier in their new places. It's easy enough to do, so I'd try un & re-plugging the cables, then swapping the switches.