I'm late to this forum on this issue. I have an SR that was purchased in July 2018 soon after it came on the market. In the last six months or so, this "Unavailable Front Radar Obstruction" error message has been popping up 7 or 8 times. The first time it happened, I thought there was something actually blocking the radar, but there was nothing when I checked. Since then, it has come on randomly, mostly when I'm on the freeway. I live in Southern California so there's no snow or anything natural that could interfere with the sensor, except for possibly direct sunlight at certain angles? Now I know I'm not the only one experiencing this, I'll mention this to the dealer next visit. Hopefully, they won't BS me.