tonight,when leaving work,I heard a beeping noise from inside the boot. Sounded like it came from the area around the passenger rear light area. I've owned the car for 2mths now and never heard it before. It sounded almost like the noise parking sensors would make,it only beeped 4x times when I turned the key and that was it! It's an 02 S3 if that makes any difference. Any ideas what it would be???