I just recently discovered a red switch mounted in the center/top of the trunk in my 2003 Volvo S40. So naturally I switched it on (was really hoping it would be a subwoofer d; ) and all I got was an annoying beep for the first three seconds every single time I put my car in reverse. Switch off, no beep. Its load, high pitched, continuous, and clearly intentional (a tiny speaker not a mechanical problem). Is this normal? What could it be for? Should I leave it on? Who knows.


Oh yeah by the way this is my second '03 S40 and I don't recall the switch or the beep in the last one. Any ideas?

 

sounds like somebody installed an after market back up warning device. Curious if your car has a trailer hitch?

 

That would make sense! I looked and there is no hitch under the bottom lip, but there is an electric connector hanging. This had a salvaged title, so maybe it was removed before sale or at the yard. As long as it is nothing to be concerned about I am happy, but I can upload images of the connector and switch if you are curious. Thanks for the tip!